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class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Virtual_storage"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.4</span> <span>Virtual storage</span> </div> </a> <ul id="toc-Virtual_storage-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Subsequent_enhancements" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Subsequent_enhancements"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.5</span> <span>Subsequent enhancements</span> </div> </a> <ul id="toc-Subsequent_enhancements-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Dual_address_space" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Dual_address_space"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.6</span> <span>Dual address space</span> </div> </a> <ul id="toc-Dual_address_space-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Extended_real_addressing" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Extended_real_addressing"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.7</span> <span>Extended real addressing</span> </div> </a> <ul id="toc-Extended_real_addressing-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Series_and_models" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Series_and_models"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Series and models</span> </div> </a> <button aria-controls="toc-Series_and_models-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Series and models subsection</span> </button> <ul id="toc-Series_and_models-sublist" class="vector-toc-list"> <li id="toc-Models_sorted_by_date_introduced_(table)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Models_sorted_by_date_introduced_(table)"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Models sorted by date introduced (table)</span> </div> </a> <ul id="toc-Models_sorted_by_date_introduced_(table)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Models_grouped_by_Model_number_(detailed)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Models_grouped_by_Model_number_(detailed)"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Models grouped by Model number (detailed)</span> </div> </a> <ul id="toc-Models_grouped_by_Model_number_(detailed)-sublist" class="vector-toc-list"> <li id="toc-System/370_Model_115" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_115"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.1</span> <span>System/370 Model 115</span> </div> </a> <ul id="toc-System/370_Model_115-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_125" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_125"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.2</span> <span>System/370 Model 125</span> </div> </a> <ul id="toc-System/370_Model_125-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_135" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_135"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.3</span> <span>System/370 Model 135</span> </div> </a> <ul id="toc-System/370_Model_135-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_138" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_138"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.4</span> <span>System/370 Model 138</span> </div> </a> <ul id="toc-System/370_Model_138-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_145" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_145"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.5</span> <span>System/370 Model 145</span> </div> </a> <ul id="toc-System/370_Model_145-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_148" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_148"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.6</span> <span>System/370 Model 148</span> </div> </a> <ul id="toc-System/370_Model_148-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_155" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_155"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.7</span> <span>System/370 Model 155</span> </div> </a> <ul id="toc-System/370_Model_155-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_158" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_158"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.8</span> <span>System/370 Model 158</span> </div> </a> <ul id="toc-System/370_Model_158-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_165" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_165"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.9</span> <span>System/370 Model 165</span> </div> </a> <ul id="toc-System/370_Model_165-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_168" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_168"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.10</span> <span>System/370 Model 168</span> </div> </a> <ul id="toc-System/370_Model_168-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370_Model_195" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370_Model_195"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.11</span> <span>System/370 Model 195</span> </div> </a> <ul id="toc-System/370_Model_195-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-System/370-compatible" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#System/370-compatible"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.12</span> <span>System/370-compatible</span> </div> </a> <ul id="toc-System/370-compatible-sublist" class="vector-toc-list"> <li id="toc-IBM_303X" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#IBM_303X"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.12.1</span> <span>IBM 303X</span> </div> </a> <ul id="toc-IBM_303X-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-IBM_308X" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#IBM_308X"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.12.2</span> <span>IBM 308X</span> </div> </a> <ul id="toc-IBM_308X-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-IBM_3090" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#IBM_3090"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.12.3</span> <span>IBM 3090</span> </div> </a> <ul id="toc-IBM_3090-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-IBM_4300" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#IBM_4300"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.12.4</span> <span>IBM 4300</span> </div> </a> <ul id="toc-IBM_4300-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-IBM_9370" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#IBM_9370"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.12.5</span> <span>IBM 9370</span> </div> </a> <ul id="toc-IBM_9370-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Clones" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Clones"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Clones</span> </div> </a> <ul id="toc-Clones-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Architecture_details" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Architecture_details"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Architecture details</span> </div> </a> <ul id="toc-Architecture_details-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-S/370_replacement" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#S/370_replacement"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>S/370 replacement</span> </div> </a> <ul id="toc-S/370_replacement-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-GCC_and_Linux_on_the_S/370" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#GCC_and_Linux_on_the_S/370"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>GCC and Linux on the S/370</span> </div> </a> <ul id="toc-GCC_and_Linux_on_the_S/370-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-I/O_evolutions" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#I/O_evolutions"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>I/O evolutions</span> </div> </a> <button aria-controls="toc-I/O_evolutions-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle I/O evolutions subsection</span> </button> <ul id="toc-I/O_evolutions-sublist" class="vector-toc-list"> <li id="toc-I/O_evolution_from_original_S/360_to_S/370" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#I/O_evolution_from_original_S/360_to_S/370"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1</span> <span>I/O evolution from original S/360 to S/370</span> </div> </a> <ul id="toc-I/O_evolution_from_original_S/360_to_S/370-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-I/O_evolution_since_original_S/370" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#I/O_evolution_since_original_S/370"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.2</span> <span>I/O evolution since original S/370</span> </div> </a> <ul id="toc-I/O_evolution_since_original_S/370-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Notes" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Notes</span> </div> </a> <ul id="toc-Notes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Further_reading" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Further_reading"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>Further reading</span> </div> </a> <ul id="toc-Further_reading-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" 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.mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">"IBM 370" redirects here. For the printer, see <a href="/wiki/IBM_370_printer" title="IBM 370 printer">IBM 370 printer</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox"><caption class="infobox-title">System/370</caption><tbody><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Ordinateurs_centraux_348-3-001-2_(edit).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fc/Ordinateurs_centraux_348-3-001-2_%28edit%29.jpg/220px-Ordinateurs_centraux_348-3-001-2_%28edit%29.jpg" decoding="async" width="220" height="248" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fc/Ordinateurs_centraux_348-3-001-2_%28edit%29.jpg/330px-Ordinateurs_centraux_348-3-001-2_%28edit%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fc/Ordinateurs_centraux_348-3-001-2_%28edit%29.jpg/440px-Ordinateurs_centraux_348-3-001-2_%28edit%29.jpg 2x" data-file-width="2640" data-file-height="2970" /></a></span></td></tr><tr><th scope="row" class="infobox-label">Designer</th><td class="infobox-data"><a href="/wiki/IBM" title="IBM">IBM</a></td></tr><tr><th scope="row" class="infobox-label">Bits</th><td class="infobox-data"><a href="/wiki/32-bit_computing" title="32-bit computing">32-bit</a></td></tr><tr><th scope="row" class="infobox-label">Introduced</th><td class="infobox-data">1970</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Computer_architecture" title="Computer architecture">Design</a></th><td class="infobox-data">CISC</td></tr><tr><th scope="row" class="infobox-label">Type</th><td class="infobox-data">Register–Register<br />Register–Memory<br />Memory–Memory</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Instruction_set" class="mw-redirect" title="Instruction set">Encoding</a></th><td class="infobox-data">Variable (2, 4 or 6 bytes long)</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Branch_(computer_science)" title="Branch (computer science)">Branching</a></th><td class="infobox-data"><a href="/wiki/Status_register" title="Status register">Condition code</a>, indexing, counting</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Endianness" title="Endianness">Endianness</a></th><td class="infobox-data">Big</td></tr><tr><th scope="row" class="infobox-label">Predecessor</th><td class="infobox-data"><a href="/wiki/System/360" class="mw-redirect" title="System/360">System/360</a></td></tr><tr><th scope="row" class="infobox-label">Successor</th><td class="infobox-data"><a href="/wiki/S/370-XA" class="mw-redirect" title="S/370-XA">S/370-XA</a>, <a href="/wiki/ESA/370" class="mw-redirect" title="ESA/370">ESA/370</a>, <a href="/wiki/ESA/390" class="mw-redirect" title="ESA/390">ESA/390</a>, <a href="/wiki/Z/Architecture" title="Z/Architecture">z/Architecture</a></td></tr><tr><th colspan="2" class="infobox-header"><a href="/wiki/Processor_register" title="Processor register">Registers</a></th></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/General-purpose_register" class="mw-redirect" title="General-purpose register">General-purpose</a></th><td class="infobox-data">16× 32-bit</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Floating_point" class="mw-redirect" title="Floating point">Floating point</a></th><td class="infobox-data"><a href="/wiki/IBM_hexadecimal_floating-point" title="IBM hexadecimal floating-point">4× 64-bit</a><sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>a<span class="cite-bracket">]</span></a></sup></td></tr></tbody></table> <style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist 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.sidebar{width:100%!important;clear:both;float:none!important;margin-left:0!important;margin-right:0!important}}body.skin--responsive .mw-parser-output .sidebar a>img{max-width:none!important}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-list-title,html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle{background:transparent!important}html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle a{color:var(--color-progressive)!important}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-list-title,html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle{background:transparent!important}html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle a{color:var(--color-progressive)!important}}@media print{body.ns-0 .mw-parser-output .sidebar{display:none!important}}</style><table class="sidebar nomobile nowraplinks plainlist"><tbody><tr><th class="sidebar-title">History of <a href="/wiki/IBM_mainframe" title="IBM mainframe">IBM mainframes</a>, 1952–present</th></tr><tr><th class="sidebar-heading"> Market name</th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/IBM_700/7000_series" title="IBM 700/7000 series">700/7000 series</a></li> <li><a href="/wiki/IBM_1400_series" title="IBM 1400 series">1400 series</a></li> <li><a href="/wiki/IBM_System/360" title="IBM System/360">System/360</a></li> <li><a class="mw-selflink selflink">System/370</a></li> <li><a href="/wiki/IBM_30XX_mainframe_lines" title="IBM 30XX mainframe lines">30XX series</a> (<a href="/wiki/IBM_303X" title="IBM 303X">303X</a>, <a href="/wiki/IBM_308X" title="IBM 308X">308X</a>, <a href="/wiki/IBM_3090" title="IBM 3090">3090</a>)</li> <li><a href="/wiki/IBM_System/390" title="IBM System/390">System/390</a></li> <li><a href="/wiki/IBM_zSeries" class="mw-redirect" title="IBM zSeries">eServer zSeries (900, 800; 990, 890)</a></li> <li><a href="/wiki/IBM_System_z9" title="IBM System z9">System z9</a></li> <li><a href="/wiki/IBM_System_z10" title="IBM System z10">System z10</a></li> <li><a href="/wiki/IBM_zEnterprise_System" class="mw-redirect" title="IBM zEnterprise System">zEnterprise System (z196, zEC12)</a></li> <li><a href="/wiki/IBM_Z" title="IBM Z"> IBM Z (z13, z14, z15, z16)</a></li></ul></td> </tr><tr><th class="sidebar-heading"> Architecture</th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/IBM_System/360_architecture" title="IBM System/360 architecture">System/360</a></li> <li><a class="mw-selflink selflink">System/370</a></li> <li><a href="/wiki/IBM_System/370-XA" title="IBM System/370-XA">S/370-XA</a></li> <li><a href="/wiki/ESA/370" class="mw-redirect" title="ESA/370">ESA/370</a></li> <li><a href="/wiki/ESA/390" class="mw-redirect" title="ESA/390">ESA/390</a></li> <li><a href="/wiki/Z/Architecture" title="Z/Architecture">z/Architecture</a></li></ul></td> </tr><tr><td class="sidebar-navbar"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:IBM_mainframes" title="Template:IBM mainframes"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:IBM_mainframes" title="Template talk:IBM mainframes"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:IBM_mainframes" title="Special:EditPage/Template:IBM mainframes"><abbr title="Edit this template">e</abbr></a></li></ul></div></td></tr></tbody></table> <p>The <b>IBM System/370</b> (<b>S/370</b>) is a range of <a href="/wiki/IBM_mainframe" title="IBM mainframe">IBM mainframe</a> computers announced as the successors to the <a href="/wiki/IBM_System/360" title="IBM System/360">System/360</a> family on June 30, 1970. The series mostly<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>b<span class="cite-bracket">]</span></a></sup> maintains <a href="/wiki/Backward_compatibility" title="Backward compatibility">backward compatibility</a> with the S/360, allowing an easy migration path for customers; this, plus improved performance, were the dominant themes of the product announcement. </p><p>Early 370 systems differed from the 360 largely in their internal circuitry, moving from the <a href="/wiki/Solid_Logic_Technology" title="Solid Logic Technology">Solid Logic Technology</a> <a href="/wiki/Hybrid_integrated_circuit" title="Hybrid integrated circuit">hybrid integrated circuits</a> containing separate transistors to more modern monolithic <a href="/wiki/Integrated_circuit" title="Integrated circuit">integrated circuits</a> containing multiple transistors per integrated circuit]], which IBM referred to as Monolithic System Technology, or MST. The higher density packaging allowed several formerly optional features from the 360 line to be included as standard features of the machines, <a href="/wiki/Floating-point" class="mw-redirect" title="Floating-point">floating-point</a> support for instance. The 370 also added a small number of new instructions. </p><p>At the time of its introduction, the development of <a href="/wiki/Virtual_memory" title="Virtual memory">virtual memory</a> systems had become a major theme in the computer market, and the 370 was considered highly controversial as it lacked this feature. This was addressed in 1972 with the System/370 Advanced Function and its associated dynamic address translation (DAT) hardware. All future machines in the lineup received this option, along with several new <a href="/wiki/Operating_system" title="Operating system">operating systems</a> that supported it. Smaller additions were made throughout the lifetime of the line, which led to a profusion of models that were generally referred to by the processor number. One of the last major additions to the line in 1988 were the <a href="/wiki/ESA/370" class="mw-redirect" title="ESA/370">ESA/370</a> extensions that allowed a machine to have multiple virtual address spaces and easily switch among them. </p><p>The 370 was IBM's primary large mainframe offering from the 1970s through the 1980s. In September 1990, the System/370 line was replaced with the <a href="/wiki/IBM_System/390" title="IBM System/390">System/390</a>. The 390, which was based on a new <a href="/wiki/ESA/390" class="mw-redirect" title="ESA/390">ESA/390</a> model, expanded the multiple memory concept to include full <a href="/wiki/Hardware_virtualization" title="Hardware virtualization">hardware virtualization</a><sup class="noprint Inline-Template" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Disputed_statement" class="mw-redirect" title="Wikipedia:Disputed statement"><span title="This claim has reliable sources with contradicting facts (April 2024)">disputed</span></a> (for: It was there earlier)  – <a href="/wiki/Talk:IBM_System/370#Multiple_operating_systems" title="Talk:IBM System/370">discuss</a></i>]</sup> that allowed it to run multiple operating systems at the same time. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Evolution">Evolution</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=1" title="Edit section: Evolution"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The original System/370 line was announced on June 30, 1970, with first customer shipment of the Models 155 and 165 planned for February 1971 and April 1971 respectively.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> The 155 first shipped in January 1971.<sup id="cite_ref-Pugh91_4-0" class="reference"><a href="#cite_note-Pugh91-4"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 643">: 643 </span></sup> System/370 underwent several architectural improvements during its roughly 20-year lifetime.<sup id="cite_ref-FOOTNOTES370D-1–D-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage506_Appendix_D._Facilities_]_5-0" class="reference"><a href="#cite_note-FOOTNOTES370D-1–D-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage506_Appendix_D._Facilities_]-5"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTES370-MVS_6-0" class="reference"><a href="#cite_note-FOOTNOTES370-MVS-6"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTES370-VM_7-0" class="reference"><a href="#cite_note-FOOTNOTES370-VM-7"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTES370-XAD-1–D-10[httpbitsaversorgpdfibm370princOpsSA22-7085-1_370-XA_Principles_of_Operation_Jan87pdfpage534_Appendix_D._Comparison_Between_System/370_and_370-XA_Modes]_8-0" class="reference"><a href="#cite_note-FOOTNOTES370-XAD-1–D-10[httpbitsaversorgpdfibm370princOpsSA22-7085-1_370-XA_Principles_of_Operation_Jan87pdfpage534_Appendix_D._Comparison_Between_System/370_and_370-XA_Modes]-8"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTESIE_9-0" class="reference"><a href="#cite_note-FOOTNOTESIE-9"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTES370-ESAD-1–D-5[httpbitsaversorgpdfibm370princOpsSA22-7200-0_370-ESA_Principles_of_Operation_Aug88pdfpage636_Appendix_D._Comparison_Between_370-XA_and_ESA/370]_10-0" class="reference"><a href="#cite_note-FOOTNOTES370-ESAD-1–D-5[httpbitsaversorgpdfibm370princOpsSA22-7200-0_370-ESA_Principles_of_Operation_Aug88pdfpage636_Appendix_D._Comparison_Between_370-XA_and_ESA/370]-10"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FOOTNOTES390-ESAD-1–D-7[httppublibzboulderibmcomepubspdfdz9ar008pdfpage947_Appendix_D._Comparison_Between_ESA/370_and_ESA/390]_11-0" class="reference"><a href="#cite_note-FOOTNOTES390-ESAD-1–D-7[httppublibzboulderibmcomepubspdfdz9ar008pdfpage947_Appendix_D._Comparison_Between_ESA/370_and_ESA/390]-11"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p><p>The following features mentioned in the 11th edition of the System/370 Principles of Operation<sup id="cite_ref-FOOTNOTES370D-1–D-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage506_Appendix_D._Facilities_]_5-1" class="reference"><a href="#cite_note-FOOTNOTES370D-1–D-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage506_Appendix_D._Facilities_]-5"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> are either optional on S/360 but standard on S/370, introduced with S/370 or added to S/370 after announcement. </p> <ul><li>Branch and Save</li> <li>Channel Indirect Data Addressing</li> <li>Channel-Set Switching</li> <li>Clear I/O</li> <li>Command Retry</li> <li>Commercial Instruction Set<sup id="cite_ref-optional_12-0" class="reference"><a href="#cite_note-optional-12"><span class="cite-bracket">[</span>c<span class="cite-bracket">]</span></a></sup></li> <li>Conditional Swapping</li> <li>CPU Timer and Clock Comparator</li> <li>Dual-Address Space (DAS)</li> <li>Extended-Precision Floating Point<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>d<span class="cite-bracket">]</span></a></sup></li> <li>Extended Real Addressing</li> <li>External Signals</li> <li>Fast Release</li> <li>Floating Point<sup id="cite_ref-optional_12-1" class="reference"><a href="#cite_note-optional-12"><span class="cite-bracket">[</span>c<span class="cite-bracket">]</span></a></sup></li> <li>Halt Device</li> <li>I/O Extended Logout</li> <li>Limited Channel Logout</li> <li>Move Inverse<sup id="cite_ref-RPQ_14-0" class="reference"><a href="#cite_note-RPQ-14"><span class="cite-bracket">[</span>e<span class="cite-bracket">]</span></a></sup></li> <li>Multiprocessing<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>f<span class="cite-bracket">]</span></a></sup></li> <li>PSW-Key Handling</li> <li>Recovery Extensions</li> <li>Segment Protection</li> <li>Service Signal</li> <li>Start-I/O-Fast Queuing<sup id="cite_ref-FOOTNOTES370-1st26-27[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage26_Start_I/O_Fast_Release]_16-0" class="reference"><a href="#cite_note-FOOTNOTES370-1st26-27[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage26_Start_I/O_Fast_Release]-16"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> (SIOF)</li> <li>Storage-Key-Instruction Extensions</li> <li>Storage-Key 4K-Byte Block</li> <li>Suspend and Resume</li> <li>Test Block</li> <li>Translation<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>g<span class="cite-bracket">]</span></a></sup></li> <li>Vector<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>h<span class="cite-bracket">]</span></a></sup></li> <li>31-Bit IDAWs</li></ul> <div class="mw-heading mw-heading3"><h3 id="Initial_models">Initial models</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=2" title="Edit section: Initial models"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>When the first System/370 machines, the <a href="/wiki/IBM_System/370_Model_155" title="IBM System/370 Model 155">Model 155</a> and the <a href="/wiki/IBM_System/370_Model_165" title="IBM System/370 Model 165">Model 165</a>, were introduced, the System/370 architecture was described as an extension, but not a redesign, of IBM's System/360 architecture which was introduced in 1964.<sup id="cite_ref-Model-165-IBM-Archives_19-0" class="reference"><a href="#cite_note-Model-165-IBM-Archives-19"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> The System/370 architecture incorporated only a small number of changes to the System/360 architecture. These changes included:<sup id="cite_ref-FOOTNOTES370-1st2–5[httpbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage5_Modifications_to_System/360]_20-0" class="reference"><a href="#cite_note-FOOTNOTES370-1st2–5[httpbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage5_Modifications_to_System/360]-20"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p> <ul><li>13 new instructions, among which were</li></ul> <dl><dd><ul><li>MOVE LONG (<b>MVCL</b>);<sup id="cite_ref-FOOTNOTES370-1st23–25[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage23_Move_Long]_21-0" class="reference"><a href="#cite_note-FOOTNOTES370-1st23–25[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage23_Move_Long]-21"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup></li> <li>COMPARE LOGICAL LONG (<b>CLCL</b>);<sup id="cite_ref-FOOTNOTES370-1st21–22[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage21_Compare_Logical_Long]_22-0" class="reference"><a href="#cite_note-FOOTNOTES370-1st21–22[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage21_Compare_Logical_Long]-22"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup></li></ul> <dl><dd><dl><dd>thereby permitting operations on up to 2^24-1 bytes (16 MB), vs. the 256-byte limits on the 360's MVC and CLC;<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup></dd></dl></dd></dl> <ul><li>SHIFT AND ROUND DECIMAL (<b>SRP</b>),<sup id="cite_ref-FOOTNOTES370-1st25–26[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage25_Shift_and_Round_Decimal]_25-0" class="reference"><a href="#cite_note-FOOTNOTES370-1st25–26[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage25_Shift_and_Round_Decimal]-25"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> which multiplied or divided a <a href="/wiki/Packed_decimal" class="mw-redirect" title="Packed decimal">packed decimal</a> value by a power of 10, rounding the result when dividing;</li></ul></dd></dl> <ul><li>optional 128-bit (<a href="/wiki/IBM_hexadecimal_floating-point" title="IBM hexadecimal floating-point">hexadecimal</a>) <a href="/wiki/Floating-point_arithmetic" title="Floating-point arithmetic">floating-point arithmetic</a>, introduced in the <a href="/wiki/IBM_System/360_Model_85" title="IBM System/360 Model 85">System/360 Model 85</a><sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup></li> <li>a new higher-resolution time-of-day clock<sup id="cite_ref-FOOTNOTES370-1st6[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage6_Time-Of_Day_Clock]_28-0" class="reference"><a href="#cite_note-FOOTNOTES370-1st6[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage6_Time-Of_Day_Clock]-28"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup></li> <li>support for the block multiplexer channel<sup id="cite_ref-FOOTNOTES37013-4–13-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage355_Types_of_Channels]_29-0" class="reference"><a href="#cite_note-FOOTNOTES37013-4–13-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage355_Types_of_Channels]-29"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> introduced in the System/360 Model 85.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup></li> <li>All of the emulator features were designed to run under the control of the standard operating systems. IBM documented the S/370 <a href="/wiki/Emulator" title="Emulator">emulator</a> programs as integrated emulators.</li></ul> <p>These models had <a href="/wiki/Core_memory" class="mw-redirect" title="Core memory">core memory</a> and did not include support for <a href="/wiki/Virtual_memory" title="Virtual memory">virtual storage</a>, as they lacked a <a href="/wiki/Memory_management_unit" title="Memory management unit">DAT (Dynamic Address Translation) box</a> </p> <div class="mw-heading mw-heading3"><h3 id="Logic_technology">Logic technology</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=3" title="Edit section: Logic technology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>All models of the System/370 used IBM's form of monolithic <a href="/wiki/Integrated_circuit" title="Integrated circuit">integrated circuits</a> called <a href="/wiki/IBM_Solid_Logic_Technology#Later_developments" class="mw-redirect" title="IBM Solid Logic Technology">MST</a> (Monolithic System Technology) making them third generation computers. MST provided System/370 with four to eight times the circuit density and over ten times the reliability when compared to the previous second generation <a href="/wiki/Solid_Logic_Technology" title="Solid Logic Technology">SLT</a> technology of the System/360.<sup id="cite_ref-Pugh91_4-1" class="reference"><a href="#cite_note-Pugh91-4"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 440">: 440 </span></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Monolithic_memory">Monolithic memory</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=4" title="Edit section: Monolithic memory"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>On September 23, 1970, IBM announced the <a href="/wiki/IBM_System/370_Model_145" title="IBM System/370 Model 145">Model 145</a>, a third model of the System/370, which was the first model to feature <a href="/wiki/Semiconductor_memory" title="Semiconductor memory">semiconductor main memory</a> made from monolithic integrated circuits and was scheduled for delivery in the late summer of 1971. All subsequent S/370 models used such memory. </p> <div class="mw-heading mw-heading3"><h3 id="Virtual_storage">Virtual storage</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=5" title="Edit section: Virtual storage"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In 1972, a very significant change was made when support for virtual storage was introduced with IBM's "System/370 Advanced Function" announcement. IBM had initially (and controversially) chosen to exclude virtual storage from the S/370 line.<sup id="cite_ref-Pugh91_4-2" class="reference"><a href="#cite_note-Pugh91-4"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 479–484">: 479–484 </span></sup><sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> The August 2, 1972 announcement included: </p> <ul><li>address relocation hardware on all S/370s except the original models 155 and 165</li> <li>the new S/370 models 158 and 168, with address relocation hardware</li> <li>four new operating systems: <a href="/wiki/DOS/VS" class="mw-redirect" title="DOS/VS">DOS/VS</a> (DOS with virtual storage), <a href="/wiki/OS/VS1" title="OS/VS1">OS/VS1</a> (<a href="/wiki/OS/360_and_successors" title="OS/360 and successors">OS/360</a> <a href="/wiki/OS/360_and_successors#OS/MFT" title="OS/360 and successors">MFT</a> with virtual storage), OS/VS2 (OS/360 <a href="/wiki/OS/360_and_successors#OS/MVT" title="OS/360 and successors">MVT</a> with virtual storage) Release 1, termed <a href="/wiki/OS/VS2_(SVS)" title="OS/VS2 (SVS)">SVS</a> (Single Virtual Storage), and Release 2, termed <a href="/wiki/MVS" title="MVS">MVS</a> (Multiple Virtual Storage) and planned to be available 20 months later (at the end of March 1974), and <a href="/wiki/VM_(operating_system)" title="VM (operating system)">VM/370</a> – the re-implemented <a href="/wiki/CP/CMS" title="CP/CMS">CP/CMS</a></li></ul> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Hist._Rechenzentrum.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Hist._Rechenzentrum.png/300px-Hist._Rechenzentrum.png" decoding="async" width="300" height="188" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Hist._Rechenzentrum.png/450px-Hist._Rechenzentrum.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Hist._Rechenzentrum.png/600px-Hist._Rechenzentrum.png 2x" data-file-width="2560" data-file-height="1600" /></a><figcaption>System/370-145 3D Rendering</figcaption></figure> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:IBM_System_370-145_und_Bandlaufwerke_2401.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/IBM_System_370-145_und_Bandlaufwerke_2401.png/300px-IBM_System_370-145_und_Bandlaufwerke_2401.png" decoding="async" width="300" height="188" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/IBM_System_370-145_und_Bandlaufwerke_2401.png/450px-IBM_System_370-145_und_Bandlaufwerke_2401.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/cd/IBM_System_370-145_und_Bandlaufwerke_2401.png/600px-IBM_System_370-145_und_Bandlaufwerke_2401.png 2x" data-file-width="2560" data-file-height="1600" /></a><figcaption>3D Rendering of computer center with IBM System/370-145 and IBM 2401 tape drives</figcaption></figure> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:IBM_370-145_2.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/IBM_370-145_2.png/300px-IBM_370-145_2.png" decoding="async" width="300" height="188" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/IBM_370-145_2.png/450px-IBM_370-145_2.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b5/IBM_370-145_2.png/600px-IBM_370-145_2.png 2x" data-file-width="2560" data-file-height="1600" /></a><figcaption>System/370-145 3D Rendering</figcaption></figure> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:IBM_370-145.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/34/IBM_370-145.png/300px-IBM_370-145.png" decoding="async" width="300" height="300" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/34/IBM_370-145.png/450px-IBM_370-145.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/34/IBM_370-145.png/600px-IBM_370-145.png 2x" data-file-width="2457" data-file-height="2457" /></a><figcaption>System/370-145 system console.</figcaption></figure> <p>Virtual storage had in fact been delivered on S/370 hardware before this announcement: </p> <ul><li>In June 1971, on the S/370-145 (one of which had to be "smuggled" into <a href="/wiki/Cambridge_Scientific_Center" title="Cambridge Scientific Center">Cambridge Scientific Center</a> to prevent anybody noticing the arrival of an S/370 at that hotbed of virtual memory development – since this would have signaled that the S/370 was about to receive address relocation technology).<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> The S/370-145 had an associative memory<sup id="cite_ref-SY24-3581-1_33-0" class="reference"><a href="#cite_note-SY24-3581-1-33"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-SY24-3581-4_34-0" class="reference"><a href="#cite_note-SY24-3581-4-34"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: CPU 117-CPU 129">: CPU 117-CPU 129 </span></sup> used by the <a href="/wiki/Microcode" title="Microcode">microcode</a> for the DOS compatibility feature from its first shipments in June 1971;<sup id="cite_ref-SY24-3581-1_33-1" class="reference"><a href="#cite_note-SY24-3581-1-33"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> the same hardware was used by the microcode for DAT.<sup id="cite_ref-SY24-3581-4_34-1" class="reference"><a href="#cite_note-SY24-3581-4-34"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: CPU 139">: CPU 139 </span></sup> Although IBM famously chose to exclude virtual storage from the S/370 announcement, that decision was being reconsidered during the completion of the 145 engineering, partly because of virtual memory experience at CSC and elsewhere. The 145 microcode architecture simplified the addition of virtual storage, allowing this capability to be present in early 145s without the extensive hardware modifications needed in other models. However, IBM did not document the 145's virtual storage capability, nor annotate the relevant bits in the control registers and PSW that were displayed on the operator control panel when selected using the roller switches. The Reference and Change bits of the Storage-protection Keys, however, were labeled on the rollers, a dead giveaway to anyone who had worked with the earlier 360/67. Existing S/370-145 customers were happy to learn that they did not have to purchase a hardware upgrade in order to run DOS/VS or OS/VS1 (or OS/VS2 Release 1 – which was possible, but not common because of the limited amount of main storage available on the S/370-145).</li></ul> <p>Shortly after the August 2, 1972 announcement, DAT box (address relocation hardware) upgrades for the S/370-155 and S/370-165 were quietly announced, but were available only for purchase by customers who already owned a Model 155 or 165.<sup id="cite_ref-S370VM_35-0" class="reference"><a href="#cite_note-S370VM-35"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> After installation, these models were known as the S/370-155-II and S/370-165-II. IBM wanted customers to upgrade their 155 and 165 systems to the widely sold S/370-158 and -168.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> These upgrades were surprisingly expensive ($200,000 and $400,000, respectively) and had long ship date lead times after being ordered by a customer; consequently, they were never popular with customers, the majority of whom leased their systems via a third-party <a href="/wiki/Lease" title="Lease">leasing</a> company.<sup id="cite_ref-S370VM_35-1" class="reference"><a href="#cite_note-S370VM-35"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> This led to the original S/370-155 and S/370-165 models being described as "boat anchors". The upgrade, required to run OS/VS1 or OS/VS2, was not cost effective for most customers by the time IBM could actually deliver and install it, so many customers were stuck with these machines running MVT until their lease ended. It was not unusual for this to be another four, five or even six years for the more unfortunate ones, and turned out to be a significant factor<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> in the slow adoption of OS/VS2 MVS, not only by customers in general, but for many internal IBM sites as well. </p> <div class="mw-heading mw-heading3"><h3 id="Subsequent_enhancements">Subsequent enhancements</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=6" title="Edit section: Subsequent enhancements"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Later architectural changes primarily involved expansions in memory (central storage) – both physical memory and virtual <a href="/wiki/Address_space" title="Address space">address space</a> – to enable larger workloads and meet client demands for more storage. This was the inevitable trend as <a href="/wiki/Moore%27s_Law" class="mw-redirect" title="Moore's Law">Moore's Law</a> eroded the unit cost of memory. As with all IBM mainframe development, preserving <a href="/wiki/Backward_compatibility" title="Backward compatibility">backward compatibility</a> was paramount.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2009)">citation needed</span></a></i>]</sup> </p> <ul><li>Operating system specific assist, Extended Control Program Support (ECPS). extended facility and extension features for OS/VS1, MVS<sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>i<span class="cite-bracket">]</span></a></sup> and VM.<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>j<span class="cite-bracket">]</span></a></sup> Exploiting levels of these operating systems, e.g., MVS/System Extensions (MVS/SE), reduce path length for some frequent functions.</li></ul> <ul><li>The Dual Address Space<sup id="cite_ref-dual-address-space-share-paper_40-0" class="reference"><a href="#cite_note-dual-address-space-share-paper-40"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> (DAS) facility allows a privileged program to move data between two address spaces without the overhead of allocating a buffer in common storage, moving the data to the buffer, scheduling an SRB in the target address space, moving the data to their final destination and freeing the buffer. IBM introduced DAS in 1981 for the <a href="/wiki/IBM_303X#IBM_3033" title="IBM 303X">3033</a>, but later made it available for some 43xx,<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> 3031 and 3032 processors. MVS/System Product (MVS/SP) Version 1 exploited DAS if it was available.</li> <li>In October 1981, the 3033 and <a href="/wiki/IBM_308X#IBM_3081" title="IBM 308X">3081</a> processors added "extended real addressing", which allowed 26-bit addressing for physical storage (but still imposed a 24-bit limit for any individual address space). This capability appeared later on other systems, such as the 4381 and 3090.<sup id="cite_ref-FOOTNOTES3703–3[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage28_Storage_Addressing_with_Extended_Address_Fields]_42-0" class="reference"><a href="#cite_note-FOOTNOTES3703–3[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage28_Storage_Addressing_with_Extended_Address_Fields]-42"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup></li> <li>The System/370 Extended Architecture (<a href="/wiki/S/370-XA" class="mw-redirect" title="S/370-XA">S/370-XA</a>), first available in early 1983 on the 3081 and 3083 processors, provided a number of major enhancements, including expansion of virtual address spaces from <a href="/wiki/24-bit_computing" title="24-bit computing">24-bits</a> to <a href="/wiki/31-bit_computing" title="31-bit computing">31-bits</a>, expansion of real addresses from 24 or 26 bits to 31 bits, and a complete redesign of the I/O architecture.</li> <li>In February 1988, IBM announced the Enterprise Systems Architecture/370 (<a href="/wiki/ESA/370" class="mw-redirect" title="ESA/370">ESA/370</a>) for enhanced (<b>E</b>) 3090 and 4381 models. It added sixteen 32-bit <a href="/wiki/Access_register" title="Access register">access registers</a>, more addressing modes, and various facilities for working with multiple address spaces simultaneously.</li> <li>On September 5, 1990, IBM announced the Enterprise Systems Architecture/390<sup id="cite_ref-MK.390_43-0" class="reference"><a href="#cite_note-MK.390-43"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> (<a href="/wiki/ESA/390" class="mw-redirect" title="ESA/390">ESA/390</a>), upward compatible with ESA/370.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Dual_address_space">Dual address space</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=7" title="Edit section: Dual address space"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In 1981, IBM added the dual-address-space facility to System/370.<sup id="cite_ref-dual-address-space-share-paper_40-1" class="reference"><a href="#cite_note-dual-address-space-share-paper-40"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> This allows a program to have two address spaces; Control Register 1 contains the segment table origin (STO) for the primary address space and CR7 contains the STO for the secondary address space. The processor can run in primary-space mode or secondary-space mode. When in primary-space mode, instructions and data are fetched from the primary address space. When in secondary-space mode, operands whose addresses defined to be logical are fetched from the secondary address space; it is unpredictable whether instructions will be fetched from the primary or secondary address space, so code must be mapped into both address spaces in the same address ranges in both address spaces. The program can switch between primary-space and secondary-space mode with the SET ADDRESS SPACE CONTROL instruction; there are also MOVE TO PRIMARY and MOVE TO SECONDARY instructions that copy a range of bytes from an address range in one address space to an address range in the other address space.<sup id="cite_ref-GA22-7000-7_44-0" class="reference"><a href="#cite_note-GA22-7000-7-44"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p><p>Address spaces are identified by an address-space number (ASN). The ASN contains indices into a two-level table, structured similarly to a two-level page table, with entries containing a presence bit, various fields indicating permissions granted for access to the address space, the starting address and length of the segment table for the address space, and other information. The SET SECONDARY ASN instruction makes the address space identified by a given ASN value the current secondary address space.<sup id="cite_ref-GA22-7000-7_44-1" class="reference"><a href="#cite_note-GA22-7000-7-44"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Extended_real_addressing">Extended real addressing</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=8" title="Edit section: Extended real addressing"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The initial System/370 architecture has a 24-bit limit on physical addresses, limiting physical memory to 16 MB. Page table entries have 12 bits of page frame address with 4 KB pages and 13 bits of page frame address with 2 KB pages, so combining a 12-bit page frame address with a 12-bit offset within the page or a 13-bit page frame address with an 11-bit offset within the page produces a 24-bit physical address.<sup id="cite_ref-FOOTNOTES3703–26[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage51_Page-Table_Entries]_45-0" class="reference"><a href="#cite_note-FOOTNOTES3703–26[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage51_Page-Table_Entries]-45"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> </p><p>The extended real addressing feature in System/370 raises this limit to 26 bits, increasing the physical memory limit to 64 MB. Two reserved bits in the page table entry for 4 KB pages were used to extend the page frame address. The extended real addressing is only available with address translation enabled and with 4 KB pages.<sup id="cite_ref-FOOTNOTES3703–26[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage51_Page-Table_Entries]_45-1" class="reference"><a href="#cite_note-FOOTNOTES3703–26[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage51_Page-Table_Entries]-45"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Series_and_models">Series and models</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=9" title="Edit section: Series and models"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Models_sorted_by_date_introduced_(table)"><span id="Models_sorted_by_date_introduced_.28table.29"></span>Models sorted by date introduced (table)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=10" title="Edit section: Models sorted by date introduced (table)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The following table summarizes the major S/370 series and models. The second column lists the principal architecture associated with each series. Many models implemented more than one architecture; thus, 308x processors initially shipped as S/370 architecture, but later offered XA; and many processors, such as the 4381, had microcode that allowed customer selection between S/370 or XA (later, ESA) operation. </p><p>Note also the confusing term "System/370-compatible", which appeared in IBM source documents to describe certain products. Outside IBM, this term would more often describe systems from <a href="/wiki/Amdahl_Corporation" title="Amdahl Corporation">Amdahl Corporation</a>, <a href="/wiki/Hitachi" title="Hitachi">Hitachi</a>, and others, that could run the same S/370 software. This choice of terminology by IBM may have been a deliberate attempt to ignore the existence of those <a href="/wiki/Plug_compatible_manufacturer" class="mw-redirect" title="Plug compatible manufacturer">plug compatible manufacturers</a> (PCMs), because they competed aggressively against IBM hardware dominance. </p> <table class="wikitable"> <tbody><tr> <th>First year<br />of series</th> <th>Architecture</th> <th>Market<br />level</th> <th>Series</th> <th>Models </th></tr> <tr> <td>1970</td> <td>System/370 (no DAT)</td> <td>high-end</td> <td rowspan="5">System/370-xxx</td> <td>-155, -165, -195 </td></tr> <tr> <td>1970</td> <td>System/370 (DAT)</td> <td>mid-range</td> <td>-145<sup id="cite_ref-model145_46-0" class="reference"><a href="#cite_note-model145-46"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> and -135 </td></tr> <tr> <td rowspan="3">1972</td> <td rowspan="3">System/370</td> <td>high-end</td> <td>-158 and -168 </td></tr> <tr> <td>entry</td> <td>-115 and -125 </td></tr> <tr> <td>mid-range</td> <td>-138 and -148 </td></tr> <tr> <td>1977</td> <td rowspan="3">System/370-compatible<sup id="cite_ref-47" class="reference"><a href="#cite_note-47"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup></td> <td>high-end</td> <td><a href="/wiki/IBM_303X" title="IBM 303X">303x</a></td> <td>3031, 3032, 3033 </td></tr> <tr> <td>1979</td> <td>entry/mid</td> <td><a href="/wiki/IBM_4300" title="IBM 4300">43xx</a></td> <td>4331, 4341, 4361 </td></tr> <tr> <td>1980</td> <td rowspan="2">high-end</td> <td rowspan="2"><a href="/wiki/IBM_308X" title="IBM 308X">308x</a></td> <td rowspan="2">3081, 3083, 3084 </td></tr> <tr> <td>1981</td> <td rowspan="3">System/370-XA </td></tr> <tr> <td>1983</td> <td>mid-range</td> <td><a href="/wiki/IBM_4300" title="IBM 4300">4381</a></td> <td>4381 </td></tr> <tr> <td>1986</td> <td>high-end</td> <td><a href="/wiki/IBM_3090" title="IBM 3090">3090</a></td> <td>-120 to -600 </td></tr> <tr> <td>1986</td> <td>System/370-compatible<sup id="cite_ref-48" class="reference"><a href="#cite_note-48"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup></td> <td>entry</td> <td><a href="/wiki/IBM_9370" title="IBM 9370">937x</a></td> <td>9370, ... </td></tr> <tr> <td>1988</td> <td rowspan="2">ESA/370</td> <td>high-end</td> <td>ES/3090</td> <td>ES/3090 </td></tr> <tr> <td>1988</td> <td>mid-range</td> <td>ES/4381</td> <td>-90, -91, -92 </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Models_grouped_by_Model_number_(detailed)"><span id="Models_grouped_by_Model_number_.28detailed.29"></span>Models grouped by Model number (detailed)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=11" title="Edit section: Models grouped by Model number (detailed)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><a href="/wiki/List_of_IBM_products#Later_solid-state_computers_&_systems" title="List of IBM products">IBM</a> used the name System/370 to announce the following eleven (three-digit) offerings: </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_115"><span id="System.2F370_Model_115"></span>System/370 Model 115</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=12" title="Edit section: System/370 Model 115"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>IBM System/370 Model 115</b> was announced March 13, 1973<sup id="cite_ref-IBM370.115_49-0" class="reference"><a href="#cite_note-IBM370.115-49"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> as "an ideal System/370 entry system for users of <a href="/wiki/IBM_System/3" title="IBM System/3">IBM's System/3</a>, <a href="/wiki/IBM_1130" title="IBM 1130">1130 computing system</a> and <a href="/wiki/IBM_System/360_Model_20" title="IBM System/360 Model 20">System/360 Models 20</a>, <a href="/wiki/IBM_System/360_Model_22" title="IBM System/360 Model 22">22</a> and <a href="/wiki/IBM_System/360_Model_25" title="IBM System/360 Model 25">25</a>." </p><p>It was delivered with "a minimum of two (of IBM's newly announced) directly attached <a href="/wiki/IBM_3340" class="mw-redirect" title="IBM 3340">IBM 3340</a> disk drives."<sup id="cite_ref-IBM370.115_49-1" class="reference"><a href="#cite_note-IBM370.115-49"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> Up to four 3340s could be attached. </p><p>The CPU could be configured with 65,536 (64K) or 98,304 (96K) bytes of main memory. An optional 360/20 emulator was available. </p><p>The 115 was withdrawn on March 9, 1981. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_125"><span id="System.2F370_Model_125"></span>System/370 Model 125</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=13" title="Edit section: System/370 Model 125"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>IBM System/370 Model 125</b> was announced Oct 4, 1972.<sup id="cite_ref-IBM370.125_50-0" class="reference"><a href="#cite_note-IBM370.125-50"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> </p><p>Two, three or four directly attached <a href="/wiki/IBM_3333" class="mw-redirect" title="IBM 3333">IBM 3333</a> disk storage units provided "up to 400 million bytes online." </p><p>Main memory was either 98,304 (96K) or 131,072 (128K) bytes. </p><p>The 125 was withdrawn on March 9, 1981. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_135"><span id="System.2F370_Model_135"></span>System/370 Model 135</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=14" title="Edit section: System/370 Model 135"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>IBM System/370 Model 135</b> was announced Mar 8, 1971.<sup id="cite_ref-IBM370.135_51-0" class="reference"><a href="#cite_note-IBM370.135-51"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> Options for the 370/135 included a choice of four main memory sizes; <a href="/wiki/IBM_1400_series" title="IBM 1400 series">IBM 1400 series</a> (1401, 1440 and 1460) emulation was also offered. </p><p>A "reading device located in the Model 135 console" allowed updates and adding features to the Model 135's microcode. </p><p>The 135 was withdrawn on October 16, 1979. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_138"><span id="System.2F370_Model_138"></span>System/370 Model 138</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=15" title="Edit section: System/370 Model 138"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>IBM System/370 Model 138</b> which was announced Jun 30, 1976 was offered with either 524,288 (512K) or 1,048,576 (1 MB) of memory. The latter was "double the maximum capacity of the Model 135," which "can be upgraded to the new computer's internal performance levels at customer locations."<sup id="cite_ref-52" class="reference"><a href="#cite_note-52"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> </p><p>The 138 was withdrawn on November 1, 1983. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_145"><span id="System.2F370_Model_145"></span>System/370 Model 145</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=16" title="Edit section: System/370 Model 145"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_System/370_Model_145" title="IBM System/370 Model 145">IBM System/370 Model 145</a></div> <p>The <b>IBM System/370 Model 145</b> was announced Sep 23, 1970, three months after the 155 and 165 models.<sup id="cite_ref-model145_46-1" class="reference"><a href="#cite_note-model145-46"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> It first shipped in June 1971.<sup id="cite_ref-Pugh91_4-3" class="reference"><a href="#cite_note-Pugh91-4"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 643">: 643 </span></sup> </p><p>The first System/370 to use monolithic main memory, the Model 145 was offered in six memory sizes. A portion of the main memory, the "Reloadable Control Storage" (RCS) was loaded from a prewritten disk cartridge containing <a href="/wiki/Microcode" title="Microcode">microcode</a> to implement, for example, all needed instructions, I/O channels, and optional instructions to enable the system to emulate earlier IBM machines.<sup id="cite_ref-model145_46-2" class="reference"><a href="#cite_note-model145-46"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> </p><p>The 145 was withdrawn on October 16, 1979. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_148"><span id="System.2F370_Model_148"></span>System/370 Model 148</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=17" title="Edit section: System/370 Model 148"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>IBM System/370 Model 148</b> had the same announcement and withdrawal dates as the Model 138.<sup id="cite_ref-53" class="reference"><a href="#cite_note-53"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> </p><p>As with the option to field-upgrade a 135, a 370/145 could be field-upgraded "at customer locations" to 148-level performance. The upgraded 135 and 145 systems were "designated the Models 135-3 and 145-3." </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_155"><span id="System.2F370_Model_155"></span>System/370 Model 155</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=18" title="Edit section: System/370 Model 155"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_System/370_Model_155" title="IBM System/370 Model 155">IBM System/370 Model 155</a></div> <p>The <b>IBM System/370 Model 155</b> and the Model 165 were announced Jun 30, 1970, the first of the 370s introduced.<sup id="cite_ref-54" class="reference"><a href="#cite_note-54"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> Neither had a DAT box; they were limited to running the same non-virtual-memory operating systems available for the <a href="/wiki/IBM_System/360" title="IBM System/360">System/360</a>. The 155 first shipped in January 1971.<sup id="cite_ref-Pugh91_4-4" class="reference"><a href="#cite_note-Pugh91-4"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 643">: 643 </span></sup> </p><p>The <i>OS/DOS</i><sup id="cite_ref-55" class="reference"><a href="#cite_note-55"><span class="cite-bracket">[</span>45<span class="cite-bracket">]</span></a></sup> (DOS/360 programs under OS/360), <i>1401/1440/1460 and 1410/7010</i><sup id="cite_ref-56" class="reference"><a href="#cite_note-56"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-57" class="reference"><a href="#cite_note-57"><span class="cite-bracket">[</span>47<span class="cite-bracket">]</span></a></sup> and <i>7070/7074</i> <sup id="cite_ref-58" class="reference"><a href="#cite_note-58"><span class="cite-bracket">[</span>48<span class="cite-bracket">]</span></a></sup> compatibility features were included, and the supporting integrated emulator programs could operate concurrently with standard System/370 workloads. </p><p>In August 1972 IBM announced, as a field upgrade only, the <b>IBM System/370 Model 155 II</b>, which added a DAT box. </p><p>Both the 155 and the 165 were withdrawn on December 23, 1977. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_158"><span id="System.2F370_Model_158"></span>System/370 Model 158</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=19" title="Edit section: System/370 Model 158"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>IBM System/370 Model 158</b> and the 370/168 were announced Aug 2, 1972.<sup id="cite_ref-IBM370.158_59-0" class="reference"><a href="#cite_note-IBM370.158-59"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> </p><p>It included dynamic address translation (DAT) hardware, a prerequisite for the new <a href="/wiki/Virtual_memory" title="Virtual memory">virtual memory</a> operating systems (DOS/VS, OS/VS1, OS/VS2). </p><p>A tightly coupled multiprocessor (MP) model was available, as was the ability to loosely couple this system to another 360 or 370 via an optional channel-to-channel adapter. </p><p>The 158 and 168 were withdrawn on September 15, 1980. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_165"><span id="System.2F370_Model_165"></span>System/370 Model 165</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=20" title="Edit section: System/370 Model 165"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_System/370_Model_165" title="IBM System/370 Model 165">IBM System/370 Model 165</a></div> <p>The <b>IBM System/370 Model 165</b> was described by IBM as "more powerful"<sup id="cite_ref-Model-165-IBM-Archives_19-1" class="reference"><a href="#cite_note-Model-165-IBM-Archives-19"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> compared to the "medium-scale" 370/155. It first shipped in April 1971.<sup id="cite_ref-Pugh91_4-5" class="reference"><a href="#cite_note-Pugh91-4"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 643">: 643 </span></sup> </p><p>Compatibility features included <a href="/wiki/Emulator" title="Emulator">emulation</a> for <a href="/wiki/IBM_700/7000_series" title="IBM 700/7000 series">7070/7074, 7080, and 709/7090/7094/7094 II</a>. </p><p>Some have described the <a href="/wiki/IBM_System/360_Model_85" title="IBM System/360 Model 85">360/85</a>'s use of <a href="/wiki/Microcode" title="Microcode">microcoded</a> vs <a href="/wiki/Hardwired_control_unit" class="mw-redirect" title="Hardwired control unit">hardwired</a> as a bridge to the 370/165.<sup id="cite_ref-60" class="reference"><a href="#cite_note-60"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup> </p><p>In August 1972 IBM announced, as a field upgrade only, the <b>IBM System/370 Model 165 II</b> which added a DAT box. </p><p>The 165 was withdrawn on December 23, 1977. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_168"><span id="System.2F370_Model_168"></span>System/370 Model 168</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=21" title="Edit section: System/370 Model 168"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_System/370_Model_168" title="IBM System/370 Model 168">IBM System/370 Model 168</a></div> <p>The <b>IBM System/370 Model 168</b> included "up to eight megabytes"<sup id="cite_ref-61" class="reference"><a href="#cite_note-61"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup> of main memory, double the maximum of 4 megabytes on the 370/158.<sup id="cite_ref-IBM370.158_59-1" class="reference"><a href="#cite_note-IBM370.158-59"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> </p><p>It included dynamic address translation (DAT) hardware, a pre-requisite for the new <a href="/wiki/Virtual_memory" title="Virtual memory">virtual memory</a> operating systems. </p><p>Although the 168 served as IBM's "flagship" system,<sup id="cite_ref-FLAG3_62-0" class="reference"><a href="#cite_note-FLAG3-62"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> a 1975 newsbrief said that IBM boosted the power of the 370/168 again "in the wake of the Amdahl challenge... only 10 months after it introduced the improved 168-3 processor."<sup id="cite_ref-63" class="reference"><a href="#cite_note-63"><span class="cite-bracket">[</span>53<span class="cite-bracket">]</span></a></sup> </p><p>The 370/168 was not withdrawn until September 1980. </p> <div class="mw-heading mw-heading4"><h4 id="System/370_Model_195"><span id="System.2F370_Model_195"></span>System/370 Model 195</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=22" title="Edit section: System/370 Model 195"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:CHM_Artifacts_(3300701247).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/61/CHM_Artifacts_%283300701247%29.jpg/220px-CHM_Artifacts_%283300701247%29.jpg" decoding="async" width="220" height="146" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/61/CHM_Artifacts_%283300701247%29.jpg/330px-CHM_Artifacts_%283300701247%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/61/CHM_Artifacts_%283300701247%29.jpg/440px-CHM_Artifacts_%283300701247%29.jpg 2x" data-file-width="4752" data-file-height="3164" /></a><figcaption>Model 195 control panel</figcaption></figure> <p>The <b>IBM System/370 Model 195</b> was announced Jun 30, 1970 and, at that time, it was "IBM's most powerful computing system."<sup id="cite_ref-ibm-archives-3195_64-0" class="reference"><a href="#cite_note-ibm-archives-3195-64"><span class="cite-bracket">[</span>54<span class="cite-bracket">]</span></a></sup> </p><p>Its introduction came about 14 months after the announcement of its direct predecessor, the <a href="/wiki/IBM_System/360_Model_195" title="IBM System/360 Model 195">360/195</a>. Both 195 machines were withdrawn Feb. 9, 1977.<sup id="cite_ref-65" class="reference"><a href="#cite_note-65"><span class="cite-bracket">[</span>55<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ibm-archives-3195_64-1" class="reference"><a href="#cite_note-ibm-archives-3195-64"><span class="cite-bracket">[</span>54<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="System/370-compatible"><span id="System.2F370-compatible"></span>System/370-compatible</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=23" title="Edit section: System/370-compatible"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Beginning in 1977, IBM began to introduce new systems, using the description "A compatible member of the System/370 family."<sup id="cite_ref-IBM.3031_66-0" class="reference"><a href="#cite_note-IBM.3031-66"><span class="cite-bracket">[</span>56<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-67" class="reference"><a href="#cite_note-67"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading5"><h5 id="IBM_303X">IBM 303X</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=24" title="Edit section: IBM 303X"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_303X" title="IBM 303X">IBM 303X</a></div> <p>The first of the initial high end machines, IBM's <b>3033</b>, was announced March 25, 1977<sup id="cite_ref-68" class="reference"><a href="#cite_note-68"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup> and was delivered the following March, at which time a multiprocessor version of the 3033 was announced.<sup id="cite_ref-69" class="reference"><a href="#cite_note-69"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> IBM described it<sup id="cite_ref-70" class="reference"><a href="#cite_note-70"><span class="cite-bracket">[</span>60<span class="cite-bracket">]</span></a></sup> as "The Big One." </p><p>IBM noted about the 3033, looking back, that "When it was rolled out on March 25, 1977, the 3033 eclipsed the internal operating speed of the company's previous flagship the System/370 Model 168-3 ..."<sup id="cite_ref-FLAG3_62-1" class="reference"><a href="#cite_note-FLAG3-62"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> </p><p>The IBM <b>3031</b> and IBM <b>3032</b> were announced Oct. 7, 1977 and withdrawn Feb. 8, 1985.<sup id="cite_ref-IBM.3031_66-1" class="reference"><a href="#cite_note-IBM.3031-66"><span class="cite-bracket">[</span>56<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-71" class="reference"><a href="#cite_note-71"><span class="cite-bracket">[</span>61<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading5"><h5 id="IBM_308X">IBM 308X</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=25" title="Edit section: IBM 308X"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_308X" title="IBM 308X">IBM 308X</a></div> <p>Three systems comprised the next series of high end machines, IBM's 308X systems: </p> <ul><li>The <b>3081</b><sup id="cite_ref-IBM.3081_72-0" class="reference"><a href="#cite_note-IBM.3081-72"><span class="cite-bracket">[</span>62<span class="cite-bracket">]</span></a></sup> (announced Nov 12, 1980) had 2 <a href="/wiki/Central_processing_unit" title="Central processing unit">CPUs</a></li> <li>The <b>3083</b><sup id="cite_ref-IBM.3083_73-0" class="reference"><a href="#cite_note-IBM.3083-73"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup> (announced Mar 31, 1982) had 1 CPU</li> <li>The <b>3084</b><sup id="cite_ref-IBM.3084_74-0" class="reference"><a href="#cite_note-IBM.3084-74"><span class="cite-bracket">[</span>64<span class="cite-bracket">]</span></a></sup> (announced Sep 3, 1982) had 4 CPUs</li></ul> <p>Despite the numbering, the least powerful was the 3083, which could be field-upgraded to a 3081;<sup id="cite_ref-IBM.3083_73-1" class="reference"><a href="#cite_note-IBM.3083-73"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup> the 3084 was the top of the line.<sup id="cite_ref-IBM.3084_74-1" class="reference"><a href="#cite_note-IBM.3084-74"><span class="cite-bracket">[</span>64<span class="cite-bracket">]</span></a></sup> </p><p>These models introduced IBM's <a href="/wiki/31-bit" class="mw-redirect" title="31-bit">Extended Architecture</a>'s 31-bit address capability<sup id="cite_ref-FOOTNOTES370-XA-1st_75-0" class="reference"><a href="#cite_note-FOOTNOTES370-XA-1st-75"><span class="cite-bracket">[</span>65<span class="cite-bracket">]</span></a></sup> and a set of <a href="/wiki/Backward_compatibility" title="Backward compatibility">backward compatible</a> MVS/Extended Architecture (MVS/XA) software replacing previous products and part of OS/VS2 R3.8: </p> <table class="wikitable"> <tbody><tr> <th>Number </th> <th style="align:left;">Name </th></tr> <tr> <td>565–279 </td> <td>Basic Telecommunications Access Method/System Product (BTAM/SP) </td></tr> <tr> <td>5668–978 </td> <td>Graphics Access Method/System Product (GAM/SP) </td></tr> <tr> <td>5740-XC6 </td> <td>MVS/System Product - JES2 Version 2 </td></tr> <tr> <td>5685–291 </td> <td>MVS/System Product - JES3 Version 2 </td></tr> <tr> <td>5665–293 </td> <td>TSO Extensions (TSO/E) for MVS/XA<sup id="cite_ref-76" class="reference"><a href="#cite_note-76"><span class="cite-bracket">[</span>66<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td>5665–284 </td> <td>MVS/Extended Architecture Data Facility Product (DFP) Version 1<sup id="cite_ref-dfp-1-2-general-information_77-0" class="reference"><a href="#cite_note-dfp-1-2-general-information-77"><span class="cite-bracket">[</span>67<span class="cite-bracket">]</span></a></sup> </td></tr></tbody></table> <p>All three 308x systems were withdrawn on August 4, 1987. </p> <div class="mw-heading mw-heading5"><h5 id="IBM_3090">IBM 3090</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=26" title="Edit section: IBM 3090"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_3090" title="IBM 3090">IBM 3090</a></div> <p>The next series of high-end machines, the <b>IBM 3090</b>, began with models<sup id="cite_ref-78" class="reference"><a href="#cite_note-78"><span class="cite-bracket">[</span>k<span class="cite-bracket">]</span></a></sup> 200 and 400.<sup id="cite_ref-79" class="reference"><a href="#cite_note-79"><span class="cite-bracket">[</span>68<span class="cite-bracket">]</span></a></sup> They were announced Feb. 12, 1985, and were configured with two or four <a href="/wiki/Central_processing_unit" title="Central processing unit">CPUs</a> respectively. IBM subsequently announced models 120, 150, 180, 300, 500 and 600 with lower, intermediate and higher capacities; the first digit of the model number gives the number of central processors. </p><p>Starting with the E<sup id="cite_ref-80" class="reference"><a href="#cite_note-80"><span class="cite-bracket">[</span>69<span class="cite-bracket">]</span></a></sup> models, and continuing with the J and S models, IBM offered Enterprise Systems Architecture/370<sup id="cite_ref-FOOTNOTES370-ESA_81-0" class="reference"><a href="#cite_note-FOOTNOTES370-ESA-81"><span class="cite-bracket">[</span>70<span class="cite-bracket">]</span></a></sup> (ESA/370), <a href="/wiki/Processor_Resource/System_Manager" class="mw-redirect" title="Processor Resource/System Manager">Processor Resource/System Manager</a> (PR/SM) and a set of backward compatible MVS/Enterprise System Architecture (MVS/ESA) software replacing previous products: </p> <table class="wikitable"> <tbody><tr> <th>Number </th> <th>Name </th></tr> <tr> <td>5685–279 </td> <td>BTAM/SP </td></tr> <tr> <td>5668–978 </td> <td>GAM/SP 2.0 </td></tr> <tr> <td>5685–001 </td> <td>MVS/System Product-JES2 Version 3<sup id="cite_ref-SP3_82-0" class="reference"><a href="#cite_note-SP3-82"><span class="cite-bracket">[</span>71<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td>5685–002 </td> <td>MVS/System Product-JES3 Version 3<sup id="cite_ref-SP3_82-1" class="reference"><a href="#cite_note-SP3-82"><span class="cite-bracket">[</span>71<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td>5665–293 </td> <td>TSO Extensions (TSO/E) for MVS/XA </td></tr> <tr> <td>5685–285 </td> <td>TSO/E Version 1 Release 4 </td></tr> <tr> <td>5685–025 </td> <td>TSO/E Version 2 </td></tr> <tr> <td>5665–284 </td> <td>MVS/XA Data Facility Product (DFP) Version 1<sup id="cite_ref-dfp-1-2-general-information_77-1" class="reference"><a href="#cite_note-dfp-1-2-general-information-77"><span class="cite-bracket">[</span>67<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td>5665-XA2 </td> <td>MVS/XA Data Facility Product (DFP) Version 2.3 </td></tr> <tr> <td>5665-XA3 </td> <td>MVS/DFP Version 3.1 </td></tr></tbody></table> <p>IBM's offering of an optional vector facility (VF) extension for the 3090 came at a time when <a href="/wiki/Vector_processing" class="mw-redirect" title="Vector processing">Vector processing</a>/Array processing suggested names like <a href="/wiki/Cray" title="Cray">Cray</a> and <a href="/wiki/Control_Data_Corporation" title="Control Data Corporation">Control Data Corporation</a> (CDC).<sup id="cite_ref-83" class="reference"><a href="#cite_note-83"><span class="cite-bracket">[</span>72<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-84" class="reference"><a href="#cite_note-84"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>The 200 and 400 were withdrawn on May 5, 1989. </p> <div class="mw-heading mw-heading5"><h5 id="IBM_4300">IBM 4300</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=27" title="Edit section: IBM 4300"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_4300" title="IBM 4300">IBM 4300</a></div> <p>The first pair of <b>IBM 4300</b> processors were Mid/Low end systems announced Jan 30, 1979<sup id="cite_ref-85" class="reference"><a href="#cite_note-85"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-86" class="reference"><a href="#cite_note-86"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup> as "compact (and).. compatible with System/370." </p><p>The 4331 was subsequently withdrawn on November 18, 1981, and the 4341 on February 11, 1986. </p><p>Other models were the 4321,<sup id="cite_ref-87" class="reference"><a href="#cite_note-87"><span class="cite-bracket">[</span>76<span class="cite-bracket">]</span></a></sup> 4361<sup id="cite_ref-IBM.4361_88-0" class="reference"><a href="#cite_note-IBM.4361-88"><span class="cite-bracket">[</span>77<span class="cite-bracket">]</span></a></sup> and 4381.<sup id="cite_ref-IBM.4381_89-0" class="reference"><a href="#cite_note-IBM.4381-89"><span class="cite-bracket">[</span>78<span class="cite-bracket">]</span></a></sup> </p><p>The 4361 has "Programmable Power-Off -- enables the user to turn off the processor under program control";<sup id="cite_ref-IBM.4361_88-1" class="reference"><a href="#cite_note-IBM.4361-88"><span class="cite-bracket">[</span>77<span class="cite-bracket">]</span></a></sup> "Unit power off" is (also) part of the 4381 feature list.<sup id="cite_ref-IBM.4381_89-1" class="reference"><a href="#cite_note-IBM.4381-89"><span class="cite-bracket">[</span>78<span class="cite-bracket">]</span></a></sup> </p><p>IBM offered many Model Groups and models of the 4300 family,<sup id="cite_ref-90" class="reference"><a href="#cite_note-90"><span class="cite-bracket">[</span>l<span class="cite-bracket">]</span></a></sup> ranging from the entry level 4331 to the 4381, described as "one of the most powerful and versatile intermediate system processors ever produced by IBM."<sup id="cite_ref-91" class="reference"><a href="#cite_note-91"><span class="cite-bracket">[</span>m<span class="cite-bracket">]</span></a></sup> </p><p>The 4381 Model Group 3 was dual-CPU. </p> <div class="mw-heading mw-heading5"><h5 id="IBM_9370">IBM 9370</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=28" title="Edit section: IBM 9370"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_9370" title="IBM 9370">IBM 9370</a></div> <p>This low-end system, announced October 7, 1986,<sup id="cite_ref-92" class="reference"><a href="#cite_note-92"><span class="cite-bracket">[</span>79<span class="cite-bracket">]</span></a></sup> was "designed to satisfy the computing requirements of IBM customers who value System/370 affinity" and "small enough and quiet enough to operate in an office environment." </p><p>IBM also noted its sensitivity to "entry software prices, substantial reductions in support and training requirements, and modest power consumption and maintenance costs." </p><p>Furthermore, it stated its awareness of the needs of small-to-medium size businesses to be able to respond, as "computing requirements grow," adding that "the IBM 9370 system can be easily expanded by adding additional features and racks to accommodate..." </p><p>This came at a time when <a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> (DEC) and its <a href="/wiki/VAX" title="VAX">VAX</a> systems were strong competitors in both hardware and software;<sup id="cite_ref-93" class="reference"><a href="#cite_note-93"><span class="cite-bracket">[</span>80<span class="cite-bracket">]</span></a></sup> the media of the day carried IBM's alleged "VAX Killer" phrase, albeit often skeptically.<sup id="cite_ref-94" class="reference"><a href="#cite_note-94"><span class="cite-bracket">[</span>81<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Clones">Clones</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=29" title="Edit section: Clones"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In the 360 era, a number of manufacturers had already standardized upon the IBM/360 instruction set and, to a degree, 360 architecture. Notable computer makers included <a href="/wiki/Univac" class="mw-redirect" title="Univac">Univac</a> with the <a href="/wiki/UNIVAC_9000_series" title="UNIVAC 9000 series">UNIVAC 9000 series</a>, <a href="/wiki/RCA" title="RCA">RCA</a> with the <a href="/wiki/RCA_Spectra_70" title="RCA Spectra 70">RCA Spectra 70</a> series, <a href="/wiki/English_Electric" title="English Electric">English Electric</a> with the <a href="/wiki/English_Electric_System_4" title="English Electric System 4">English Electric System 4</a>, and the Soviet <a href="/wiki/ES_EVM" title="ES EVM">ES EVM</a>. These computers were not perfectly compatible, nor (except for the Russian efforts)<sup id="cite_ref-95" class="reference"><a href="#cite_note-95"><span class="cite-bracket">[</span>82<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-96" class="reference"><a href="#cite_note-96"><span class="cite-bracket">[</span>83<span class="cite-bracket">]</span></a></sup> were they intended to be. </p><p>That changed in the 1970s with the introduction of the IBM/370 and <a href="/wiki/Gene_Amdahl" title="Gene Amdahl">Gene Amdahl</a>'s launch of his own company. About the same time, Japanese giants began eyeing the lucrative mainframe market both at home and abroad. One Japanese consortium focused upon IBM and two others from the <a href="/wiki/BUNCH" title="BUNCH">BUNCH</a> (<b>B</b>urroughs/<b>U</b>nivac/<b>N</b>CR/<b>C</b>ontrol Data/<b>H</b>oneywell) group of IBM's competitors.<sup id="cite_ref-97" class="reference"><a href="#cite_note-97"><span class="cite-bracket">[</span>84<span class="cite-bracket">]</span></a></sup> The latter efforts were abandoned and eventually all Japanese efforts focused on the IBM mainframe lines. </p><p>Some of the era's clones included: </p> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col" style="column-width: 18em;"> <ul><li><a href="/wiki/Amdahl_Corporation" title="Amdahl Corporation">Amdahl Corporation</a> 470 series</li> <li><a href="/wiki/ES_EVM" title="ES EVM">ES EVM</a></li> <li><a href="/wiki/Fujitsu" title="Fujitsu">Fujitsu</a></li> <li><a href="/wiki/Hitachi" title="Hitachi">Hitachi</a></li> <li><a href="/wiki/Magnuson_Computer_Systems" title="Magnuson Computer Systems">Magnuson Computer Systems</a></li> <li><a href="/wiki/Mitsubishi" title="Mitsubishi">Mitsubishi</a></li> <li><a href="/wiki/Siemens" title="Siemens">Siemens</a></li> <li>Two Pi Corporation<sup id="cite_ref-98" class="reference"><a href="#cite_note-98"><span class="cite-bracket">[</span>85<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Univac" class="mw-redirect" title="Univac">Univac</a></li></ul></div> <div class="mw-heading mw-heading2"><h2 id="Architecture_details">Architecture details</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=30" title="Edit section: Architecture details"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>IBM documentation numbers the bits from high order to low order; the most significant (leftmost) bit is designated as bit number 0. </p> <table class="infobox" style="font-size:88%"> <caption align="center"><i>IBM S/370 registers</i> </caption> <tbody><tr> <td style="border-style: none;"> <table class="wikitable" style="font-size:75%"> <caption>General Registers 0–15 </caption> <tbody><tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td colspan="32">Two's complement value </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">0 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">31 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr></tbody></table> </td></tr> <tr> <td style="border-style: none;"> <table class="wikitable" style="font-size:75%"> <caption>Control Registers 0–15 </caption> <tbody><tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td colspan="32">See Principles of Operation<sup id="cite_ref-FOOTNOTES3704-10–4-11[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage83_Assignment_of_Control-Register_Fields]_99-0" class="reference"><a href="#cite_note-FOOTNOTES3704-10–4-11[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage83_Assignment_of_Control-Register_Fields]-99"><span class="cite-bracket">[</span>86<span class="cite-bracket">]</span></a></sup> </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">0 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">31 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr></tbody></table> </td></tr> <tr> <td style="border-style: none;"> <table class="wikitable" style="font-size:75%"> <caption>Floating Point Registers 0–6 </caption> <tbody><tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td>S </td> <td colspan="7">Biased exponent </td> <td colspan="24">Mantissa </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">0 </td> <td style="width:1%; text-align:left; border-style: none none none none;">1 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">7 </td> <td style="width:1%; text-align:left; border-style: none none none none;">8 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">31 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td colspan="32">Mantissa (continued) </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">32 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">63 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr></tbody></table> </td></tr> <tr> <td style="border-style: none;"> <table class="wikitable" style="font-size:75%"> <caption>S/370 <b>B</b>asic <b>C</b>ontrol mode PSW<sup id="cite_ref-FOOTNOTES3704-8_–&#32,_4–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage81_Program-Status_Word_Format_in_BC_Mode]_100-0" class="reference"><a href="#cite_note-FOOTNOTES3704-8_–&#32,_4–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage81_Program-Status_Word_Format_in_BC_Mode]-100"><span class="cite-bracket">[</span>87<span class="cite-bracket">]</span></a></sup> </caption> <tbody><tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td colspan="6">Chan.<br />Mask </td> <td>I<br />O </td> <td>E<br />X </td> <td colspan="4">Key </td> <td>0 </td> <td>M </td> <td>W </td> <td>P </td> <td colspan="16">Interruption Code </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">0 </td> <td style="width:1%; text-align:left; border-style: none none none none;">1 </td> <td style="width:1%; text-align:left; border-style: none none none none;">2 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">4 </td> <td style="width:1%; text-align:left; border-style: none none none none;">5 </td> <td style="width:1%; text-align:left; border-style: none none none none;">6 </td> <td style="width:1%; text-align:left; border-style: none none none none;">7 </td> <td style="width:1%; text-align:left; border-style: none none none none;">8 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">11 </td> <td style="width:1%; text-align:left; border-style: none none none none;">12 </td> <td style="width:1%; text-align:left; border-style: none none none none;">13 </td> <td style="width:1%; text-align:left; border-style: none none none none;">14 </td> <td style="width:1%; text-align:left; border-style: none none none none;">15 </td> <td style="width:1%; text-align:left; border-style: none none none none;">16 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">31 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td colspan="2">ILC </td> <td colspan="2">CC </td> <td colspan="4">Program<br />Mask </td> <td colspan="24">Instruction Address </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">32 </td> <td style="width:1%; text-align:right; border-style: none none none none;">33 </td> <td style="width:1%; text-align:left; border-style: none none none none;">34 </td> <td style="width:1%; text-align:right; border-style: none none none none;">35 </td> <td style="width:1%; text-align:left; border-style: none none none none;">36 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">39 </td> <td style="width:1%; text-align:left; border-style: none none none none;">40 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;'">63 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td colspan="34" style="border-style: none;"> <table class="wikitable mw-collapsible autocollapse"> <caption><span class="nowrap">S/370 BC mode PSW abbreviations</span> </caption> <tbody><tr> <th style="width:10%; text-align:left;">Bits </th> <th style="width:10%; text-align:left;">Field </th> <th style="width:80%; text-align:left;">Meaning </th></tr> <tr> <td>0–5 </td> <td> </td> <td>Channel Masks for channels 0–5 </td></tr> <tr> <td>6 </td> <td>IO </td> <td>I/O Mask for channels > 5 </td></tr> <tr> <td>7 </td> <td>EX </td> <td>External Mask </td></tr> <tr> <td>8–11 </td> <td>Key </td> <td>PSW key </td></tr> <tr> <td>12 </td> <td>E=0 </td> <td><b>B</b>asic <b>C</b>ontrol mode </td></tr> <tr> <td>13 </td> <td>M </td> <td>Machine-check mask </td></tr> <tr> <td>14 </td> <td>W </td> <td>Wait state </td></tr> <tr> <td>15 </td> <td>P </td> <td>Problem state </td></tr> <tr> <td>16–31 </td> <td>IC </td> <td>Interruption Code<sup id="cite_ref-FOOTNOTES3706-3_–&#32,_6–5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage154_Interruption_Action]_101-0" class="reference"><a href="#cite_note-FOOTNOTES3706-3_–&#32,_6–5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage154_Interruption_Action]-101"><span class="cite-bracket">[</span>88<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td>32–33 </td> <td>ILC </td> <td>Instruction-Length Code<sup id="cite_ref-FOOTNOTES3706-7_–&#32,_6–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage158_Instruction-Length_Code]_102-0" class="reference"><a href="#cite_note-FOOTNOTES3706-7_–&#32,_6–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage158_Instruction-Length_Code]-102"><span class="cite-bracket">[</span>89<span class="cite-bracket">]</span></a></sup> </td></tr> <tr> <td>34–35 </td> <td>CC </td> <td>Condition Code </td></tr> <tr> <td>36–39 </td> <td>PM </td> <td> <table class="wikitable mw-collapsible autocollapse"> <caption style="text-align: left;"><span class="nowrap">Program Mask</span> </caption> <tbody><tr> <th>Bit </th> <th>Meaning </th></tr> <tr> <td>36 </td> <td>Fixed-point overflow </td></tr> <tr> <td>37 </td> <td>Decimal overflow </td></tr> <tr> <td>38 </td> <td>Exponent underflow </td></tr> <tr> <td>39 </td> <td>Significance </td></tr></tbody></table> </td></tr> <tr> <td>40–63 </td> <td>IA </td> <td>Instruction Address </td></tr></tbody></table> </td></tr></tbody></table> </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="border-style: none;"> <table class="wikitable" style="font-size:75%"> <caption>S/370 <b>E</b>xtended <b>C</b>ontrol mode PSW<sup id="cite_ref-FOOTNOTES3704-6_–&#32,_4–7[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage79_Program-Status_Word_Format_in_EC_Mode]_103-0" class="reference"><a href="#cite_note-FOOTNOTES3704-6_–&#32,_4–7[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage79_Program-Status_Word_Format_in_EC_Mode]-103"><span class="cite-bracket">[</span>90<span class="cite-bracket">]</span></a></sup> </caption> <tbody><tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td>0 </td> <td>R </td> <td style="border-style: solid none solid solid">0 </td> <td style="border-style: solid none solid">0 </td> <td style="border-style: solid solid solid none">0 </td> <td>T </td> <td>I<br />O </td> <td>E<br />X </td> <td colspan="4">Key </td> <td>1 </td> <td>M </td> <td>W </td> <td>P </td> <td>S </td> <td>0 </td> <td colspan="2">CC </td> <td colspan="4">Program<br />Mask </td> <td style="border-style: solid none solid solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid solid solid none;">0 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">0 </td> <td style="width:1%; text-align:left; border-style: none none none none;">1 </td> <td style="width:1%; text-align:left; border-style: none none none none;">2 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">4 </td> <td style="width:1%; text-align:left; border-style: none none none none;">5 </td> <td style="width:1%; text-align:left; border-style: none none none none;">6 </td> <td style="width:1%; text-align:left; border-style: none none none none;">7 </td> <td style="width:1%; text-align:left; border-style: none none none none;">8 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">11 </td> <td style="width:1%; text-align:left; border-style: none none none none;">12 </td> <td style="width:1%; text-align:left; border-style: none none none none;">13 </td> <td style="width:1%; text-align:left; border-style: none none none none;">14 </td> <td style="width:1%; text-align:left; border-style: none none none none;">15 </td> <td style="width:1%; text-align:left; border-style: none none none none;">16 </td> <td style="width:1%; text-align:right; border-style: none none none none;">17 </td> <td style="width:1%; text-align:left; border-style: none none none none;">18 </td> <td style="width:1%; text-align:right; border-style: none none none none;">19 </td> <td style="width:1%; text-align:left; border-style: none none none none;">20 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">23 </td> <td style="width:1%; text-align:left; border-style: none none none none;">24 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;">31 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td colspan="34" style="border-style: none;"><br /> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="border-style: solid none solid solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid none solid;">0 </td> <td style="border-style: solid solid solid none;">0 </td> <td colspan="24">Instruction Address </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;">32 </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:left; border-style: none none none none;"> </td> <td style="width:1%; text-align:right; border-style: none none none none;'">63 </td> <td style="width:.5%; text-align:left; border-style: none none none none;"> </td></tr> <tr> <td colspan="34" style="border-style: none;"> <table class="wikitable mw-collapsible autocollapse"> <caption><span class="nowrap">S/370 EC mode PSW abbreviations</span> </caption> <tbody><tr> <th style="width:10%; text-align:left;">Bits </th> <th style="width:10%; text-align:left;">Field </th> <th style="width:80%; text-align:left;">Meaning </th></tr> <tr> <td>1 </td> <td>R </td> <td>PER Mask </td></tr> <tr> <td>5 </td> <td>T </td> <td>DAT mode </td></tr> <tr> <td>6 </td> <td>IO </td> <td>I/O Mask; subject to channel mask in CR2 </td></tr> <tr> <td>7 </td> <td>EX </td> <td>External Mask; subject to external subclass mask in CR0 </td></tr> <tr> <td>8–11 </td> <td>Key </td> <td>PSW key </td></tr> <tr> <td>12 </td> <td>E=1 </td> <td><b>E</b>xtended <b>C</b>ontrol mode </td></tr> <tr> <td>13 </td> <td>M </td> <td>Machine-check mask </td></tr> <tr> <td>14 </td> <td>W </td> <td>Wait state </td></tr> <tr> <td>15 </td> <td>P </td> <td>Problem state </td></tr> <tr> <td>16 </td> <td>S </td> <td>Address-Space Control<br />0=primary-space mode<br />1=Secondary-space mode </td></tr> <tr> <td>18–19 </td> <td>CC </td> <td>Condition Code </td></tr> <tr> <td>20–23 </td> <td>PM </td> <td> <table class="wikitable mw-collapsible autocollapse"> <caption style="text-align: left;"><span class="nowrap">Program Mask</span> </caption> <tbody><tr> <th>Bit </th> <th>Meaning </th></tr> <tr> <td>20 </td> <td>Fixed-point overflow </td></tr> <tr> <td>21 </td> <td>Decimal overflow </td></tr> <tr> <td>22 </td> <td>Exponent underflow </td></tr> <tr> <td>23 </td> <td>Significance </td></tr></tbody></table> </td></tr> <tr> <td>40–63 </td> <td>IA </td> <td>Instruction Address </td></tr></tbody></table> </td></tr></tbody></table> </td></tr></tbody></table> <p>S/370 also refers to a <a href="/wiki/Computer_architecture" title="Computer architecture">computer system architecture</a> specification,<sup id="cite_ref-FOOTNOTES370_104-0" class="reference"><a href="#cite_note-FOOTNOTES370-104"><span class="cite-bracket">[</span>91<span class="cite-bracket">]</span></a></sup> and is a direct and mostly <a href="/wiki/Backward_compatible" class="mw-redirect" title="Backward compatible">backward compatible</a> evolution of the System/360 architecture<sup id="cite_ref-FOOTNOTES3701-1_–&#32,_1–4[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage16_Chapter_1_Introduction]_105-0" class="reference"><a href="#cite_note-FOOTNOTES3701-1_–&#32,_1–4[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage16_Chapter_1_Introduction]-105"><span class="cite-bracket">[</span>92<span class="cite-bracket">]</span></a></sup> from which it retains most aspects. This specification does not make any assumptions on the implementation itself, but rather describes the interfaces and the expected behavior of an implementation. The architecture describes mandatory interfaces that must be available on all implementations and optional interfaces which may or may not be implemented. </p><p>Some of the aspects of this architecture are: </p> <ul><li><a href="/wiki/Big_endian" class="mw-redirect" title="Big endian">Big endian</a> byte ordering</li> <li>One or more processors with: <ul><li>16 32-bit General purpose <a href="/wiki/Processor_register" title="Processor register">registers</a></li> <li>16 32-bit Control registers</li> <li>4 64-bit <a href="/wiki/IBM_hexadecimal_floating-point" title="IBM hexadecimal floating-point">Floating-point</a> registers</li> <li>A 64-bit Program status word (PSW) which describes (among other things) <ul><li><a href="/wiki/Interrupt" title="Interrupt">Interrupt</a> masks</li> <li>Privilege states</li> <li>A condition code</li> <li>A 24-bit <a href="/wiki/Program_counter" title="Program counter">instruction address</a></li></ul></li> <li>Timing facilities (Time of day clock, interval timer, CPU timer and clock comparator)</li> <li>An interruption mechanism, <a href="/wiki/Interrupt" title="Interrupt">maskable</a> and unmaskable interruption classes and subclasses</li> <li>An <a href="/wiki/Instruction_set" class="mw-redirect" title="Instruction set">instruction set</a>. Each instruction is wholly described and also defines the conditions under which an exception is recognized in the form of program interruption.</li></ul></li> <li>A <a href="/wiki/Primary_storage" class="mw-redirect" title="Primary storage">memory (called storage) subsystem</a> with: <ul><li>8 bits per byte</li> <li>A special processor communication area starting at address 0</li> <li>Key controlled protection</li> <li>24-bit addressing</li></ul></li> <li>Manual control operations that provide: <ul><li>A <a href="/wiki/Booting" title="Booting">bootstrap</a> process (a process called Initial Program Load or IPL)</li> <li>Operator-initiated interrupts</li> <li>Resetting the system</li> <li>Basic debugging facilities</li> <li>Manual display and modifications of the system's state (memory and processor)</li></ul></li> <li>An Input/Output mechanism – which does not describe the devices themselves</li></ul> <p>Some of the optional features are: </p> <ul><li>A <a href="/wiki/Virtual_memory#History" title="Virtual memory">Dynamic Address Translation</a> (DAT) mechanism that can be used to implement a <a href="/wiki/Virtual_memory" title="Virtual memory">virtual memory</a> system</li> <li><a href="/wiki/Floating_point" class="mw-redirect" title="Floating point">Floating point</a> instructions</li></ul> <p>IBM took great care to ensure that changes to the architecture would remain compatible for unprivileged (problem state) programs; some new interfaces did not break the initial interface contract for privileged (supervisor mode) programs. Some examples are </p> <dl><dt>ECPS:MVS<sup id="cite_ref-106" class="reference"><a href="#cite_note-106"><span class="cite-bracket">[</span>93<span class="cite-bracket">]</span></a></sup></dt> <dd>A feature to enhance performance for the <a href="/wiki/MVS/370" class="mw-redirect" title="MVS/370">MVS/370</a> operating systems</dd> <dt>ECPS:VM<sup id="cite_ref-107" class="reference"><a href="#cite_note-107"><span class="cite-bracket">[</span>94<span class="cite-bracket">]</span></a></sup></dt> <dd>A feature to enhance performance for the <a href="/wiki/VM_(operating_system)" title="VM (operating system)">VM</a> operating systems</dd></dl> <p>Other changes were compatible only for unprivileged programs, although the changes for privileged programs were of limited scope and well defined. Some examples are: </p> <dl><dt>ECPS:VSE<sup id="cite_ref-108" class="reference"><a href="#cite_note-108"><span class="cite-bracket">[</span>95<span class="cite-bracket">]</span></a></sup></dt> <dd>A feature to enhance performance for the <a href="/wiki/DOS/VSE" class="mw-redirect" title="DOS/VSE">DOS/VSE</a> operating system.</dd> <dt>S/370-XA<sup id="cite_ref-FOOTNOTES370-XA-1st_75-1" class="reference"><a href="#cite_note-FOOTNOTES370-XA-1st-75"><span class="cite-bracket">[</span>65<span class="cite-bracket">]</span></a></sup></dt> <dd>A feature to provide a new I/O interface and to support <a href="/wiki/31-bit_computing" title="31-bit computing">31-bit</a> virtual and physical addressing</dd></dl> <p>Great care was taken in order to ensure that further modifications to the architecture would remain compatible, at least as far as non-privileged programs were concerned. This philosophy predates the definition of the S/370 architecture and started with the S/360 architecture. If certain rules are adhered to, a program written for this architecture will run with the intended results on the successors of this architecture. </p><p>Such an example is that the S/370 architecture specifies that the 64-bit PSW register bit number 32 has to be set to 0 and that doing otherwise leads to an exception. Subsequently, when the S/370-XA architecture was defined, it was stated that this bit would indicate whether the program was a program expecting a 24-bit address architecture or 31-bit address architecture. Thus, most programs that ran on the 24-bit architecture can still run on 31-bit systems; the 64-bit <a href="/wiki/Z/Architecture" title="Z/Architecture">z/Architecture</a> has an additional mode bit for 64-bit addresses, so that those programs, and programs that ran on the 31-bit architecture, can still run on 64-bit systems. </p><p>However, not all of the interfaces can remain compatible. Emphasis was put on having non control programs (called problem state programs) remain compatible.<sup id="cite_ref-FOOTNOTES390-ESA1-13_–&#32,_1–14[httppublibzboulderibmcomepubspdfdz9ar008pdfpage45_Section_1.3.2.2_Problem-State_Compatibility]_109-0" class="reference"><a href="#cite_note-FOOTNOTES390-ESA1-13_–&#32,_1–14[httppublibzboulderibmcomepubspdfdz9ar008pdfpage45_Section_1.3.2.2_Problem-State_Compatibility]-109"><span class="cite-bracket">[</span>96<span class="cite-bracket">]</span></a></sup> Thus, operating systems have to be ported to the new architecture because the control interfaces can (and were) redefined in an incompatible way. For example, the I/O interface was redesigned in S/370-XA making S/370 program issuing I/O operations unusable as-is. </p> <div class="mw-heading mw-heading2"><h2 id="S/370_replacement"><span id="S.2F370_replacement"></span>S/370 replacement</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=31" title="Edit section: S/370 replacement"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>IBM replaced the System/370 line with the <a href="/wiki/IBM_System/390" title="IBM System/390">System/390</a> in the 1990s, and similarly extended the architecture from ESA/370 to ESA/390. This was a minor architectural change, and was upwards compatible. </p><p>In 2000, the System/390 was replaced with the <a href="/wiki/IBM_System_z" class="mw-redirect" title="IBM System z">zSeries</a> (now called IBM Z). The zSeries mainframes introduced the 64-bit <a href="/wiki/Z/Architecture" title="Z/Architecture">z/Architecture</a>, the most significant design improvement since the 31-bit transition.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2009)">citation needed</span></a></i>]</sup> All have retained essential backward compatibility with the original S/360 architecture and instruction set. </p> <div class="mw-heading mw-heading2"><h2 id="GCC_and_Linux_on_the_S/370"><span id="GCC_and_Linux_on_the_S.2F370"></span>GCC and Linux on the S/370</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=32" title="Edit section: GCC and Linux on the S/370"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/GNU_Compiler_Collection" title="GNU Compiler Collection">GNU Compiler Collection</a> (GCC) had a <a href="/wiki/Compiler_back-end" class="mw-redirect" title="Compiler back-end">back end</a> for S/370, but it became obsolete over time and was finally replaced with the S/390 backend. Although the S/370 and S/390 instruction sets are essentially the same (and have been consistent since the introduction of the S/360), GCC operability on older systems has been abandoned.<sup id="cite_ref-110" class="reference"><a href="#cite_note-110"><span class="cite-bracket">[</span>97<span class="cite-bracket">]</span></a></sup> GCC currently works on machines that have the full instruction set of System/390 Generation 5 (G5), the hardware platform for the initial release of <a href="/wiki/Linux_on_IBM_Z" title="Linux on IBM Z">Linux/390</a>. However, a separately maintained version of GCC 3.2.3 that works for the S/370 is available, known as GCCMVS.<sup id="cite_ref-111" class="reference"><a href="#cite_note-111"><span class="cite-bracket">[</span>98<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="I/O_evolutions"><span id="I.2FO_evolutions"></span>I/O evolutions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=33" title="Edit section: I/O evolutions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="I/O_evolution_from_original_S/360_to_S/370"><span id="I.2FO_evolution_from_original_S.2F360_to_S.2F370"></span>I/O evolution from original S/360 to S/370</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=34" title="Edit section: I/O evolution from original S/360 to S/370"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/IBM_System/360#Channels" title="IBM System/360">IBM System/360 § Channels</a></div> <p>The block multiplexer channel, previously available only on the 360/85 and 360/195, was a standard part of the architecture. For compatibility it could operate as a selector channel.<sup id="cite_ref-FOOTNOTES37013-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage356_Programming_Note]_112-0" class="reference"><a href="#cite_note-FOOTNOTES37013-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage356_Programming_Note]-112"><span class="cite-bracket">[</span>99<span class="cite-bracket">]</span></a></sup> Block multiplexer channels were available in single byte (1.5 MB/s) and double byte (3.0 MB/s) versions. </p> <div class="mw-heading mw-heading3"><h3 id="I/O_evolution_since_original_S/370"><span id="I.2FO_evolution_since_original_S.2F370"></span>I/O evolution since original S/370</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=35" title="Edit section: I/O evolution since original S/370"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>As part of the DAT announcement, IBM upgraded channels to have Indirect Data Address Lists (IDALs). a form of I/O MMU. </p><p>Data streaming channels had a speed of 3.0 MB/s over a single byte interface, later upgraded to 4.5 MB/s. </p><p>Channel set switching allowed one processor in a multiprocessor configuration to take over the I/O workload from the other processor if it failed or was taken offline for maintenance. </p><p>System/370-XA introduced a channel subsystem that performed I/O queuing previously done by the operating system. </p><p>The System/390 introduced the <a href="/wiki/ESCON" title="ESCON">ESCON</a> channel, an <a href="/wiki/Optical_fiber" title="Optical fiber">optical fiber</a>, <a href="/wiki/Half-duplex" class="mw-redirect" title="Half-duplex">half-duplex</a>, <a href="/wiki/Serial_communications" class="mw-redirect" title="Serial communications">serial</a> channel with a maximum distance of 43 kilometers. Originally operating at 10 Mbyte/s, it was subsequently increased to 17 Mbyte/s. </p><p>Subsequently, <a href="/wiki/FICON" title="FICON">FICON</a> became the standard IBM mainframe channel; FIbre CONnection (FICON) is the IBM proprietary name for the <a href="/wiki/ANSI" class="mw-redirect" title="ANSI">ANSI</a> FC-SB-3 Single-Byte Command Code Sets-3 Mapping Protocol for <a href="/wiki/Fibre_Channel" title="Fibre Channel">Fibre Channel</a> (FC) protocol used to map both IBM's antecedent (either <a href="/wiki/ESCON" title="ESCON">ESCON</a> or parallel Bus and Tag) channel-to-control-unit cabling infrastructure and protocol onto standard FC services and infrastructure at data rates up to 16 Gigabits/sec at distances up to 100 km. <a href="/wiki/Fibre_Channel_Protocol" title="Fibre Channel Protocol">Fibre Channel Protocol</a> (FCP) allows attaching SCSI devices using the same infrastructure as FICON. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=36" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Hercules_emulator" class="mw-redirect" title="Hercules emulator">Hercules emulator</a></li> <li><a href="/wiki/IBM_System/360" title="IBM System/360">IBM System/360</a></li> <li><a href="/wiki/IBM_System/370-XA" title="IBM System/370-XA">IBM System/370-XA</a></li> <li><a href="/wiki/IBM_ESA/390" class="mw-redirect" title="IBM ESA/390">IBM ESA/390</a></li> <li><a href="/wiki/IBM_System_z" class="mw-redirect" title="IBM System z">IBM System z</a></li> <li><a href="/wiki/PC-based_IBM-compatible_mainframes" class="mw-redirect" title="PC-based IBM-compatible mainframes">PC-based IBM-compatible mainframes</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=37" title="Edit section: Notes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-lower-alpha"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text">16 FP registers in S/390</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">E.g., programs that depended on getting program interrupts for alignment errors might fail.</span> </li> <li id="cite_note-optional-12"><span class="mw-cite-backlink">^ <a href="#cite_ref-optional_12-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-optional_12-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">Optional on S/360</span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text">Previously available on S/360 models <a href="/wiki/IBM_System/360_Model_85" title="IBM System/360 Model 85">85</a> and <a href="/wiki/IBM_System/360_Model_195" title="IBM System/360 Model 195">195</a></span> </li> <li id="cite_note-RPQ-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-RPQ_14-0">^</a></b></span> <span class="reference-text">Available as an RPQ on S/360</span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text">Previously available on S/360 models <a href="/wiki/IBM_System/360_Model_65" title="IBM System/360 Model 65">65</a> and <a href="/wiki/IBM_System/360_Model_67" title="IBM System/360 Model 67">67</a>, and on the <a href="/wiki/IBM_9020" title="IBM 9020">9020</a></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text">The Dynamic Address Translation on S/370 is different from that on the <a href="/wiki/IBM_System/360_Model_67" title="IBM System/360 Model 67">360/67</a></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text">Only on the <a href="/wiki/IBM_3090" title="IBM 3090">3090</a></span> </li> <li id="cite_note-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-38">^</a></b></span> <span class="reference-text">One of these<sup id="cite_ref-FOOTNOTES370-MVS_6-1" class="reference"><a href="#cite_note-FOOTNOTES370-MVS-6"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> is required for MVS/SE and MVS/SP <ul><li>System/370 extended facility</li> <li>ECPS:MVS</li> <li>3033 extension feature</li></ul> </span></li> <li id="cite_note-39"><span class="mw-cite-backlink"><b><a href="#cite_ref-39">^</a></b></span> <span class="reference-text">VM/370 R2, VM/BSE, VM/SE and VM/SP exploit Virtual-Machine Assist and Shadow-Table-Bypass Assist<sup id="cite_ref-FOOTNOTES370-VM_7-1" class="reference"><a href="#cite_note-FOOTNOTES370-VM-7"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> if they are available.</span> </li> <li id="cite_note-78"><span class="mw-cite-backlink"><b><a href="#cite_ref-78">^</a></b></span> <span class="reference-text">IBM used a lower case "m"</span> </li> <li id="cite_note-90"><span class="mw-cite-backlink"><b><a href="#cite_ref-90">^</a></b></span> <span class="reference-text">One announcement alone featured mention of "Twelve models of the 4381" for just 3 "Model Groups" and also listed 6 other Model Groups</span> </li> <li id="cite_note-91"><span class="mw-cite-backlink"><b><a href="#cite_ref-91">^</a></b></span> <span class="reference-text">The same IBM web page notes the following date announced/withdrawn dates: Model Groups <b>1 & 2</b> (Sep 15, 1983 - Feb 11, 1986), Model Group <b>3</b> (Oct 25, 1984 - Feb 11, 1986), Model Groups <b>11, 12, 13 & 14</b> (announced Feb 11, 1986), Model Groups <b>21, 22, 23 & 24</b> (May 19, 1987 - Aug 19, 1992).</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=38" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <dl><dt><b>S370-1st</b></dt> <dd><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFS370-1st" class="citation book cs1"><a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/ibm/370/princOps/GA22-7000-0_370_Principles_Of_Operation_Jun70.pdf"><i>IBM System/370 Principles of Operation</i></a> <span class="cs1-format">(PDF)</span> (First ed.). IBM. June 1970. A22-7000-0.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Principles+of+Operation&rft.edition=First&rft.pub=IBM&rft.date=1970-06&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fibm%2F370%2FprincOps%2FGA22-7000-0_370_Principles_Of_Operation_Jun70.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt><b>S370</b></dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS370" class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf"><i>IBM System/370 Principles of Operation</i></a> <span class="cs1-format">(PDF)</span> (Eleventh ed.). IBM. September 1987. A22-7000-10.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Principles+of+Operation&rft.edition=Eleventh&rft.pub=IBM&rft.date=1987-09&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FprincOps%2FGA22-7000-10_370_Principles_of_Operation_Sep87.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt><b>S370-MVS</b></dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS370-MVS" class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/MVS/GA22-7079-1_IBM_System_370_Assists_for_MVS_Oct81.pdf"><i>IBM System/370 Assists for MVS</i></a> <span class="cs1-format">(PDF)</span> (Second ed.). IBM. October 1981. GA22-7079-1.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Assists+for+MVS&rft.edition=Second&rft.pub=IBM&rft.date=1981-10&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FMVS%2FGA22-7079-1_IBM_System_370_Assists_for_MVS_Oct81.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt><b>S370-VM</b></dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS370-VM" class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/VM/370/GA22-7074-0_Virtual-Machine_Assist_and_Shadow-Table-Bypass_Assist_May80.pdf"><i>Virtual-Machine Assist and Shadow-Table-Bypass Assist</i></a> <span class="cs1-format">(PDF)</span> (First ed.). IBM. May 1980. GA22-7074-0<span class="reference-accessdate">. Retrieved <span class="nowrap">2024-09-19</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Virtual-Machine+Assist+and+Shadow-Table-Bypass+Assist&rft.edition=First&rft.pub=IBM&rft.date=1980-05&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FVM%2F370%2FGA22-7074-0_Virtual-Machine_Assist_and_Shadow-Table-Bypass_Assist_May80.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt><b>S370-XA-1st</b></dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS370-XA-1st" class="citation book cs1"><a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/ibm/370/princOps/SA22-7085-0_370-XA_Principles_of_Operation_Mar83.pdf"><i>IBM System/370 Extended Architecture Principles of Operation</i></a> <span class="cs1-format">(PDF)</span>. IBM. March 1983. SA22-7085-0.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Extended+Architecture+Principles+of+Operation&rft.pub=IBM&rft.date=1983-03&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fibm%2F370%2FprincOps%2FSA22-7085-0_370-XA_Principles_of_Operation_Mar83.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt><b>S370-XA</b></dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS370-XA" class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/SA22-7085-1_370-XA_Principles_of_Operation_Jan87.pdf"><i>IBM System/370 Extended Architecture Principles of Operation</i></a> <span class="cs1-format">(PDF)</span> (Second ed.). IBM. January 1987. SA22-7085-1.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Extended+Architecture+Principles+of+Operation&rft.edition=Second&rft.pub=IBM&rft.date=1987-01&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FprincOps%2FSA22-7085-1_370-XA_Principles_of_Operation_Jan87.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt><b>S370-ESA</b></dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS370-ESA" class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/SA22-7200-0_370-ESA_Principles_of_Operation_Aug88.pdf"><i>IBM Enterprise Systems Architecture/370 Principles of Operation</i></a> <span class="cs1-format">(PDF)</span> (First ed.). IBM. August 1988. SA22-7200-0.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+Enterprise+Systems+Architecture%2F370+Principles+of+Operation&rft.edition=First&rft.pub=IBM&rft.date=1988-08&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FprincOps%2FSA22-7200-0_370-ESA_Principles_of_Operation_Aug88.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt><b>S/390-ESA</b></dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFS390-ESA" class="citation book cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230129050211/http://publibz.boulder.ibm.com/epubs/pdf/dz9ar008.pdf"><i>IBM Enterprise Systems Architecture/390 Principles of Operation</i></a> <span class="cs1-format">(PDF)</span> (Ninth ed.). IBM. June 2003. SA22-7201-08. Archived from <a rel="nofollow" class="external text" href="http://publibz.boulder.ibm.com/epubs/pdf/dz9ar008.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2023-01-29<span class="reference-accessdate">. Retrieved <span class="nowrap">2021-01-01</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+Enterprise+Systems+Architecture%2F390+Principles+of+Operation&rft.edition=Ninth&rft.pub=IBM&rft.date=2003-06&rft_id=http%3A%2F%2Fpublibz.boulder.ibm.com%2Fepubs%2Fpdf%2Fdz9ar008.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd> <dt>SIE</dt> <dd><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSIE" class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/MVS_XA/SA22-7095-0_370-XA_Interpretive_Execution_Jan84.pdf"><i>IBM System/370 Extended Architecture Interpretive Execution</i></a> <span class="cs1-format">(PDF)</span> (First ed.). IBM. January 1984. SA22-7095-0.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Extended+Architecture+Interpretive+Execution&rft.edition=First&rft.pub=IBM&rft.date=1984-01&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FMVS_XA%2FSA22-7095-0_370-XA_Interpretive_Execution_Jan84.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></dd></dl> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PR370.html">"System/370 Announcement"</a>. <a href="/wiki/IBM" title="IBM">IBM</a>. June 30, 1970.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=System%2F370+Announcement&rft.pub=IBM&rft.date=1970-06-30&rft_id=http%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PR370.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-Pugh91-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-Pugh91_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Pugh91_4-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Pugh91_4-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Pugh91_4-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Pugh91_4-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Pugh91_4-5"><sup><i><b>f</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPughL.R._JohnsonJohn_H._Palmer1991" class="citation book cs1">Pugh, E.W.; L.R. Johnson; John H. Palmer (1991). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/ibms360early370s0000pugh"><i>IBM's 360 and early 370 systems</i></a></span>. Cambridge: MIT Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-262-16123-0" title="Special:BookSources/0-262-16123-0"><bdi>0-262-16123-0</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM%27s+360+and+early+370+systems&rft.place=Cambridge&rft.pub=MIT+Press&rft.date=1991&rft.isbn=0-262-16123-0&rft.aulast=Pugh&rft.aufirst=E.W.&rft.au=L.R.+Johnson&rft.au=John+H.+Palmer&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fibms360early370s0000pugh&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES370D-1–D-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage506_Appendix_D._Facilities_]-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTES370D-1–D-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage506_Appendix_D._Facilities_]_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTES370D-1–D-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage506_Appendix_D._Facilities_]_5-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. D-1–D-5, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=506">Appendix D. Facilities </a>.</span> </li> <li id="cite_note-FOOTNOTES370-MVS-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTES370-MVS_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTES370-MVS_6-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFS370-MVS">S370-MVS</a>.</span> </li> <li id="cite_note-FOOTNOTES370-VM-7"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTES370-VM_7-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTES370-VM_7-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFS370-VM">S370-VM</a>.</span> </li> <li id="cite_note-FOOTNOTES370-XAD-1–D-10[httpbitsaversorgpdfibm370princOpsSA22-7085-1_370-XA_Principles_of_Operation_Jan87pdfpage534_Appendix_D._Comparison_Between_System/370_and_370-XA_Modes]-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370-XAD-1–D-10[httpbitsaversorgpdfibm370princOpsSA22-7085-1_370-XA_Principles_of_Operation_Jan87pdfpage534_Appendix_D._Comparison_Between_System/370_and_370-XA_Modes]_8-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370-XA">S370-XA</a>, pp. D-1–D-10, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/SA22-7085-1_370-XA_Principles_of_Operation_Jan87.pdf#page=534">Appendix D. Comparison Between System/370 and 370-XA Modes</a>.</span> </li> <li id="cite_note-FOOTNOTESIE-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESIE_9-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSIE">SIE</a>.</span> </li> <li id="cite_note-FOOTNOTES370-ESAD-1–D-5[httpbitsaversorgpdfibm370princOpsSA22-7200-0_370-ESA_Principles_of_Operation_Aug88pdfpage636_Appendix_D._Comparison_Between_370-XA_and_ESA/370]-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370-ESAD-1–D-5[httpbitsaversorgpdfibm370princOpsSA22-7200-0_370-ESA_Principles_of_Operation_Aug88pdfpage636_Appendix_D._Comparison_Between_370-XA_and_ESA/370]_10-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370-ESA">S370-ESA</a>, pp. D-1–D-5, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/SA22-7200-0_370-ESA_Principles_of_Operation_Aug88.pdf#page=636">Appendix D. Comparison Between 370-XA and ESA/370</a>.</span> </li> <li id="cite_note-FOOTNOTES390-ESAD-1–D-7[httppublibzboulderibmcomepubspdfdz9ar008pdfpage947_Appendix_D._Comparison_Between_ESA/370_and_ESA/390]-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES390-ESAD-1–D-7[httppublibzboulderibmcomepubspdfdz9ar008pdfpage947_Appendix_D._Comparison_Between_ESA/370_and_ESA/390]_11-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS390-ESA">S390-ESA</a>, pp. D-1–D-7, <a rel="nofollow" class="external text" href="http://publibz.boulder.ibm.com/epubs/pdf/dz9ar008.pdf#page=947">Appendix D. Comparison Between ESA/370 and ESA/390</a>.</span> </li> <li id="cite_note-FOOTNOTES370-1st26-27[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage26_Start_I/O_Fast_Release]-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370-1st26-27[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage26_Start_I/O_Fast_Release]_16-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370-1st">S370-1st</a>, p. 26-27, <a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/ibm/370/princOps/GA22-7000-0_370_Principles_Of_Operation_Jun70.pdf#page=26">Start I/O Fast Release</a>.</span> </li> <li id="cite_note-Model-165-IBM-Archives-19"><span class="mw-cite-backlink">^ <a href="#cite_ref-Model-165-IBM-Archives_19-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Model-165-IBM-Archives_19-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230729090329/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3165.html">"System/370 Model 165"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3165.html">the original</a> on 2023-07-29.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+165&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3165.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES370-1st2–5[httpbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage5_Modifications_to_System/360]-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370-1st2–5[httpbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage5_Modifications_to_System/360]_20-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370-1st">S370-1st</a>, pp. 2–5, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-0_370_Principles_Of_Operation_Jun70.pdf#page=5">Modifications to System/360</a>.</span> </li> <li id="cite_note-FOOTNOTES370-1st23–25[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage23_Move_Long]-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370-1st23–25[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage23_Move_Long]_21-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370-1st">S370-1st</a>, pp. 23–25, <a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/ibm/370/princOps/GA22-7000-0_370_Principles_Of_Operation_Jun70.pdf#page=23">Move Long</a>.</span> </li> <li id="cite_note-FOOTNOTES370-1st21–22[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage21_Compare_Logical_Long]-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370-1st21–22[httpwwwbitsaversorgpdfibm370princOpsGA22-7000-0_370_Principles_Of_Operation_Jun70pdfpage21_Compare_Logical_Long]_22-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370-1st">S370-1st</a>, pp. 21–22, <a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/ibm/370/princOps/GA22-7000-0_370_Principles_Of_Operation_Jun70.pdf#page=21">Compare Logical Long</a>.</span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://faculty.cs.niu.edu/~byrnes/csci360/notes/360ex.htm">"Move Character Long"</a>. <i>CSCI 360 Computer Programming in the Assembler Language</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=CSCI+360+Computer+Programming+in+the+Assembler+Language&rft.atitle=Move+Character+Long&rft_id=http%3A%2F%2Ffaculty.cs.niu.edu%2F~byrnes%2Fcsci360%2Fnotes%2F360ex.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCasePadegs" class="citation book cs1">Case, Richard P.; Padegs, Andris. <a rel="nofollow" class="external text" href="http://research.microsoft.com/en-us/um/people/gbell/tcmwebpage/timeline/chap51_ibm370_cs2.pdf">"Architecture of the IBM System/370"</a> <span class="cs1-format">(PDF)</span>. In <a href="/wiki/Gordon_Bell" title="Gordon Bell">Bell, C. 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IBM.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Announcing%3A+System%2F370+Model+155&rft.pub=IBM&rft_id=http%3A%2F%2Fed-thelen.org%2Fcomp-hist%2FIBM-ProdAnn%2F370-155.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://ed-thelen.org/comp-hist/IBM-ProdAnn/370-165.pdf">"Announcing System/370 Model 165"</a> <span class="cs1-format">(PDF)</span>. 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IBM. SY24-3581-4.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+Maintenance+Library+3145+Processing+Unit+Theory+-+Maintenance&rft.edition=Fifth&rft.pub=IBM&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fibm%2F370%2Ffe%2F3145%2FSY24-3581-4_3145_Processor_Theory_Maintenance.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-S370VM-35"><span class="mw-cite-backlink">^ <a href="#cite_ref-S370VM_35-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-S370VM_35-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">"IBM's Virtual Memory 370s," Datamation, September 1972, p.58-61</span> </li> <li id="cite_note-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-36">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFA._Padegs1981" class="citation journal cs1">A. Padegs (September 1981). "System/360 and Beyond". <i>IBM Journal of Research & Development</i>. <b>25</b> (5). IBM: 377–390. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1147%2Frd.255.0377">10.1147/rd.255.0377</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IBM+Journal+of+Research+%26+Development&rft.atitle=System%2F360+and+Beyond&rft.volume=25&rft.issue=5&rft.pages=377-390&rft.date=1981-09&rft_id=info%3Adoi%2F10.1147%2Frd.255.0377&rft.au=A.+Padegs&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span> – tables include model characteristics (Table 1) and announcement/shipment dates (Table 2). The S/370-155-II and -165-II are listed under the former but not the latter, because the upgraded systems were not formally announced as separate models. The "System/370 Advanced Function" announcement, including the -158 and -168, was the main public event.</span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text">"155, 165 Owners Angry with IBM," Datamation, August 1973, p.76-86</span> </li> <li id="cite_note-dual-address-space-share-paper-40"><span class="mw-cite-backlink">^ <a href="#cite_ref-dual-address-space-share-paper_40-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-dual-address-space-share-paper_40-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDan_Greiner2012" class="citation conference cs1">Dan Greiner (12 March 2012). <a rel="nofollow" class="external text" href="https://share.confex.com/share/118/webprogram/Session10446.html"><i>Dual Address Space & Linkage-Stack Architecture</i></a>. <a rel="nofollow" class="external text" href="https://share.confex.com/share/118/webprogram/">SHARE 118 Atlanta</a>. Session 10446. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210114021953/https://share.confex.com/share/118/webprogram/Session10446.html">Archived</a> from the original on 2021-01-14.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=Dual+Address+Space+%26+Linkage-Stack+Architecture&rft.date=2012-03-12&rft.au=Dan+Greiner&rft_id=https%3A%2F%2Fshare.confex.com%2Fshare%2F118%2Fwebprogram%2FSession10446.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-41">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/4381/GC20-2021-2_A_Guide_to_the_IBM_4381_Processor_Apr1986.pdf#page=137">"Section 80: Comparison Table of Hardware - 4341 Model Group 12 and 4381 Processors"</a> <span class="cs1-format">(PDF)</span>. <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/4381/GC20-2021-2_A_Guide_to_the_IBM_4381_Processor_Apr1986.pdf"><i>A Guide to the IBM 4381 Processor</i></a> <span class="cs1-format">(PDF)</span> (Third ed.). IBM. April 1986. p. 128. GC20·2021·2.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Section+80%3A+Comparison+Table+of+Hardware+-+4341+Model+Group+12+and+4381+Processors&rft.btitle=A+Guide+to+the+IBM+4381+Processor&rft.pages=128&rft.edition=Third&rft.pub=IBM&rft.date=1986-04&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F4381%2FGC20-2021-2_A_Guide_to_the_IBM_4381_Processor_Apr1986.pdf%23page%3D137&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES3703–3[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage28_Storage_Addressing_with_Extended_Address_Fields]-42"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES3703–3[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage28_Storage_Addressing_with_Extended_Address_Fields]_42-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 3–3, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=28">Storage Addressing with Extended Address Fields</a>.</span> </li> <li id="cite_note-MK.390-43"><span class="mw-cite-backlink"><b><a href="#cite_ref-MK.390_43-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20231026082859/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PR390.html">"System/390 Announcement"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PR390.html">the original</a> on 2023-10-26<span class="reference-accessdate">. Retrieved <span class="nowrap">2017-01-29</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F390+Announcement&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PR390.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-GA22-7000-7-44"><span class="mw-cite-backlink">^ <a href="#cite_ref-GA22-7000-7_44-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-GA22-7000-7_44-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.trailing-edge.com/pdf/ibm/370/princOps/GA22-7000-7_IBM_System_370_Principles_of_Operation_8th_ed_198103.pdf"><i>IBM System/370 Principles of Operation</i></a> <span class="cs1-format">(PDF)</span> (Eighth ed.). <a href="/wiki/IBM" title="IBM">IBM</a>. September 1981. p. 3-11-3-6,5-11-5-29. GA22-7000-7.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Principles+of+Operation&rft.pages=3%26%2345%3B11-3%26%2345%3B6%2C5%26%2345%3B11-5%26%2345%3B29&rft.edition=Eighth&rft.pub=IBM&rft.date=1981-09&rft_id=http%3A%2F%2Fbitsavers.trailing-edge.com%2Fpdf%2Fibm%2F370%2FprincOps%2FGA22-7000-7_IBM_System_370_Principles_of_Operation_8th_ed_198103.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES3703–26[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage51_Page-Table_Entries]-45"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTES3703–26[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage51_Page-Table_Entries]_45-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTES3703–26[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage51_Page-Table_Entries]_45-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 3–26, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=51">Page-Table Entries</a>.</span> </li> <li id="cite_note-model145-46"><span class="mw-cite-backlink">^ <a href="#cite_ref-model145_46-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-model145_46-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-model145_46-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230729090334/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3145.html">"System/370 Model 145"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3145.html">the original</a> on 2023-07-29.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+145&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3145.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-47"><span class="mw-cite-backlink"><b><a href="#cite_ref-47">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_basinfo.html">"IBM timeline of S/370 series"</a>. <i><a href="/wiki/IBM" title="IBM">IBM</a></i>. 23 January 2003.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM&rft.atitle=IBM+timeline+of+S%2F370+series&rft.date=2003-01-23&rft_id=http%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_basinfo.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span> with surprising term 'System/370-compatible' for the 3xxx and 4xxx series</span> </li> <li id="cite_note-48"><span class="mw-cite-backlink"><b><a href="#cite_ref-48">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS186-178&open&cm_mmc=5733-_-n-_-vrm_newsletter-_-10207_134134&cmibm_em=dm:0:12046832#">"IBM 9370 announcement letter"</a>. <i><a href="/wiki/IBM" title="IBM">IBM</a></i>. 7 October 1986.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM&rft.atitle=IBM+9370+announcement+letter&rft.date=1986-10-07&rft_id=http%3A%2F%2Fwww.ibm.com%2Fcommon%2Fssi%2Fcgi-bin%2Fssialias%3Fsubtype%3Dca%26infotype%3Dan%26appname%3DiSource%26supplier%3D897%26letternum%3DENUS186-178%26open%26cm_mmc%3D5733-_-n-_-vrm_newsletter-_-10207_134134%26cmibm_em%3Ddm%3A0%3A12046832%23&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span> to explain why the 9370 is categorized as a System/370 compatible system</span> </li> <li id="cite_note-IBM370.115-49"><span class="mw-cite-backlink">^ <a href="#cite_ref-IBM370.115_49-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-IBM370.115_49-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719144824/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3115.html">"System/370 Model 115"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3115.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+115&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3115.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM370.125-50"><span class="mw-cite-backlink"><b><a href="#cite_ref-IBM370.125_50-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719145726/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3125.html">"System/370 Model 125"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3125.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+125&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3125.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM370.135-51"><span class="mw-cite-backlink"><b><a href="#cite_ref-IBM370.135_51-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719221316/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3135.html">"System/370 Model 135"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3135.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+135&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3135.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-52"><span class="mw-cite-backlink"><b><a href="#cite_ref-52">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719144824/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3138.html">"System/370 Model 138"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3138.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+138&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3138.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-53"><span class="mw-cite-backlink"><b><a href="#cite_ref-53">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719145815/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3148.html">"System/370 Model 148"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3148.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+148&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3148.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-54"><span class="mw-cite-backlink"><b><a href="#cite_ref-54">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230516082850/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3155.html">"System/370 Model 155"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3155.html">the original</a> on 2023-05-16.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+155&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3155.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-55"><span class="mw-cite-backlink"><b><a href="#cite_ref-55">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><i>IBM System/360 Operating System: DOS Emulator Planning Guide</i>. IBM. GC24-5076.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F360+Operating+System%3A+DOS+Emulator+Planning+Guide&rft.pub=IBM&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-56"><span class="mw-cite-backlink"><b><a href="#cite_ref-56">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs2"><i>Emulating the IBM 1401, 1440 and 1460 on the IBM System/370 Models 145 and 155 using OS/360 Program Number 360C-EU-735</i> (Second ed.), IBM, February 1971, GC27-6945-1</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Emulating+the+IBM+1401%2C+1440+and+1460+on+the+IBM+System%2F370+Models+145+and+155+using+OS%2F360+Program+Number+360C-EU-735&rft.edition=Second&rft.pub=IBM&rft.date=1971-02&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-57"><span class="mw-cite-backlink"><b><a href="#cite_ref-57">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs2"><i>Emulating the IBM 1410 and 7010 on the IBM System/370 Models 145 and 155 using OS/360 Program Number 360C-EU-736</i> (Second ed.), IBM, June 1971, GC27-6946-1</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Emulating+the+IBM+1410+and+7010+on+the+IBM+System%2F370+Models+145+and+155+using+OS%2F360+Program+Number+360C-EU-736&rft.edition=Second&rft.pub=IBM&rft.date=1971-06&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-58"><span class="mw-cite-backlink"><b><a href="#cite_ref-58">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><i>Emulating the IBM 7074 on the IBM System/370 Models 155 and 165 using OS/360 Program Number 360C-EU-739</i> (Second ed.). IBM. February 1971. GC27-6948-1.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Emulating+the+IBM+7074+on+the+IBM+System%2F370+Models+155+and+165+using+OS%2F360+Program+Number+360C-EU-739&rft.edition=Second&rft.pub=IBM&rft.date=1971-02&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM370.158-59"><span class="mw-cite-backlink">^ <a href="#cite_ref-IBM370.158_59-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-IBM370.158_59-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20210301143132/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3158.html">"System/370 Model 158"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3158.html">the original</a> on 2021-03-01.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+158&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3158.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-60"><span class="mw-cite-backlink"><b><a href="#cite_ref-60">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJon_Elson2014" class="citation newsgroup cs1">Jon Elson (December 5, 2014). <a rel="nofollow" class="external text" href="https://groups.google.com/d/topic/alt.folklore.computers/OHWBCMBqwKY">"IBM 360/85 vs. 370/165"</a>. <a href="/wiki/Usenet_newsgroup" title="Usenet newsgroup">Newsgroup</a>: <a rel="nofollow" class="external text" href="news:alt.folklore.computers">alt.folklore.computers</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=IBM+360%2F85+vs.+370%2F165&rft.pub=alt.folklore.computers&rft.date=2014-12-05&rft.au=Jon+Elson&rft_id=https%3A%2F%2Fgroups.google.com%2Fd%2Ftopic%2Falt.folklore.computers%2FOHWBCMBqwKY&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-61"><span class="mw-cite-backlink"><b><a href="#cite_ref-61">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20231205223819/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3168.html">"System/370 Model 168"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3168.html">the original</a> on 2023-12-05.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+168&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3168.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FLAG3-62"><span class="mw-cite-backlink">^ <a href="#cite_ref-FLAG3_62-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FLAG3_62-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230928083308/https://www.ibm.com/ibm/history/exhibits/3033/3033_intro.html">"IBM's 3033 "The Big One": IBM's 3033"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/3033/3033_intro.html">the original</a> on 2023-09-28.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=IBM%27s+3033+%22The+Big+One%22%3A+IBM%27s+3033&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2F3033%2F3033_intro.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-63"><span class="mw-cite-backlink"><b><a href="#cite_ref-63">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation news cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20151208061017/http://www.tnmoc.org/news/notes-museum/winter-19756-pages-computer-weekly">"IBM boosts power of 370/168 again"</a>. <i><a href="/wiki/Computer_Weekly" title="Computer Weekly">Computer Weekly</a></i>. No. 486. 1975. p. 1. Archived from <a rel="nofollow" class="external text" href="http://www.tnmoc.org/news/notes-museum/winter-19756-pages-computer-weekly">the original</a> on December 8, 2015.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Computer+Weekly&rft.atitle=IBM+boosts+power+of+370%2F168+again&rft.issue=486&rft.pages=1&rft.date=1975&rft_id=http%3A%2F%2Fwww.tnmoc.org%2Fnews%2Fnotes-museum%2Fwinter-19756-pages-computer-weekly&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-ibm-archives-3195-64"><span class="mw-cite-backlink">^ <a href="#cite_ref-ibm-archives-3195_64-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-ibm-archives-3195_64-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230729090333/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3195.html">"System/370 Model 195"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3195.html">the original</a> on 2023-07-29.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F370+Model+195&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3195.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-65"><span class="mw-cite-backlink"><b><a href="#cite_ref-65">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230729090329/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP2195.html">"System/360 Model 195"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP2195.html">the original</a> on 2023-07-29.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=System%2F360+Model+195&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP2195.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM.3031-66"><span class="mw-cite-backlink">^ <a href="#cite_ref-IBM.3031_66-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-IBM.3031_66-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719144802/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3031.html">"3031 Processor Complex"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3031.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3031+Processor+Complex&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3031.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-67"><span class="mw-cite-backlink"><b><a href="#cite_ref-67">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230922112055/http://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_basinfo.html">"Mainframes - Basic information sources"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="http://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_basinfo.html">the original</a> on 2023-09-22.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=Mainframes+-+Basic+information+sources&rft.date=2003-01-23&rft_id=http%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_basinfo.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-68"><span class="mw-cite-backlink"><b><a href="#cite_ref-68">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719145845/https://www.ibm.com/ibm/history/exhibits/3033/3033_PR01.html">"3033 Press announcement"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/3033/3033_PR01.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3033+Press+announcement&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2F3033%2F3033_PR01.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-69"><span class="mw-cite-backlink"><b><a href="#cite_ref-69">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719223056/https://www.ibm.com/ibm/history/exhibits/3033/3033_PR02.html">"3033 Multiprocessor - Press announcement"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/3033/3033_PR02.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3033+Multiprocessor+-+Press+announcement&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2F3033%2F3033_PR02.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-70"><span class="mw-cite-backlink"><b><a href="#cite_ref-70">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230928083308/https://www.ibm.com/ibm/history/exhibits/3033/3033_intro.html">"IBM's 3033 "The Big One": IBM's 3033"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/3033/3033_intro.html">the original</a> on 2023-09-28. <q><i>THINK</i> magazine later simply dubbed it – "The Big One."<span class="cs1-kern-right"></span></q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=IBM%27s+3033+%22The+Big+One%22%3A+IBM%27s+3033&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2F3033%2F3033_intro.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-71"><span class="mw-cite-backlink"><b><a href="#cite_ref-71">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719144906/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3032.html">"3032 Processor Complex"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3032.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3032+Processor+Complex&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3032.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM.3081-72"><span class="mw-cite-backlink"><b><a href="#cite_ref-IBM.3081_72-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719144956/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3081.html">"3081 Processor Complex"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3081.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3081+Processor+Complex&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3081.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM.3083-73"><span class="mw-cite-backlink">^ <a href="#cite_ref-IBM.3083_73-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-IBM.3083_73-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719144956/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3083.html">"3083 Processor Complex"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3083.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3083+Processor+Complex&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3083.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM.3084-74"><span class="mw-cite-backlink">^ <a href="#cite_ref-IBM.3084_74-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-IBM.3084_74-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20231210232532/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3084.html">"3084 Processor Complex"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3084.html">the original</a> on 2023-12-10.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3084+Processor+Complex&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3084.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES370-XA-1st-75"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTES370-XA-1st_75-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTES370-XA-1st_75-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFS370-XA-1st">S370-XA-1st</a>.</span> </li> <li id="cite_note-76"><span class="mw-cite-backlink"><b><a href="#cite_ref-76">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation cs2"><a rel="nofollow" class="external text" href="https://www.ibm.com/common/ssi/rep_ca/6/877/ENUSZP81-0796/"><i>TSO Extensions (TSO/E), which enhances and extends the capability of TSO, is announced</i></a>, Announcement Letters, IBM, November 2, 1981, ZP81-0796</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=TSO+Extensions+%28TSO%2FE%29%2C+which+enhances+and+extends+the+capability+of+TSO%2C+is+announced&rft.series=Announcement+Letters&rft.pub=IBM&rft.date=1981-11-02&rft_id=https%3A%2F%2Fwww.ibm.com%2Fcommon%2Fssi%2Frep_ca%2F6%2F877%2FENUSZP81-0796%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-dfp-1-2-general-information-77"><span class="mw-cite-backlink">^ <a href="#cite_ref-dfp-1-2-general-information_77-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-dfp-1-2-general-information_77-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/MVS_XA/DFP/GC26-4007-2_MVS_XA_DFP_Release_1.2_General_Information_Jan1984.pdf"><i>MVS/Extended Architecture Data Facility Product: General Information</i></a> <span class="cs1-format">(PDF)</span> (Third ed.). IBM. January 1984<span class="reference-accessdate">. Retrieved <span class="nowrap">2024-09-19</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=MVS%2FExtended+Architecture+Data+Facility+Product%3A+General+Information&rft.edition=Third&rft.pub=IBM&rft.date=1984-01&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FMVS_XA%2FDFP%2FGC26-4007-2_MVS_XA_DFP_Release_1.2_General_Information_Jan1984.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-79"><span class="mw-cite-backlink"><b><a href="#cite_ref-79">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20231204192300/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3090.html">"3090 Processor Complex"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3090.html">the original</a> on 2023-12-04.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=3090+Processor+Complex&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP3090.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-80"><span class="mw-cite-backlink"><b><a href="#cite_ref-80">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ibm.com/common/ssi/rep_ca/0/897/ENUS187-110/index.html">"IBM 3090 PROCESSOR UNIT MODEL 120E, IBM 3092 PROCESSOR CONTROLLER MODEL 3"</a>. IBM. May 19, 1987.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=IBM+3090+PROCESSOR+UNIT+MODEL+120E%2C+IBM+3092+PROCESSOR+CONTROLLER+MODEL+3&rft.pub=IBM&rft.date=1987-05-19&rft_id=http%3A%2F%2Fwww.ibm.com%2Fcommon%2Fssi%2Frep_ca%2F0%2F897%2FENUS187-110%2Findex.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES370-ESA-81"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370-ESA_81-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370-ESA">S370-ESA</a>.</span> </li> <li id="cite_note-SP3-82"><span class="mw-cite-backlink">^ <a href="#cite_ref-SP3_82-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-SP3_82-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=dd&subtype=sm&htmlfid=897/ENUS5685-001#Header_43"><i>5685-001 MVS/System Product-JES2 Version 3 Release 1.0</i></a>. IBM Sales Manual. IBM. 8 August 2001.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=5685-001+MVS%2FSystem+Product-JES2+Version+3+Release+1.0&rft.series=IBM+Sales+Manual&rft.pub=IBM&rft.date=2001-08-08&rft_id=https%3A%2F%2Fwww.ibm.com%2Fcommon%2Fssi%2Fcgi-bin%2Fssialias%3Finfotype%3Ddd%26subtype%3Dsm%26htmlfid%3D897%2FENUS5685-001%23Header_43&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-83"><span class="mw-cite-backlink"><b><a href="#cite_ref-83">^</a></b></span> <span class="reference-text">the hyperlink on the words "Vector processing" point to an article that has only 2 mentions of IBM, one of which begins "In 2000, IBM, Toshiba and Sony collaborated."</span> </li> <li id="cite_note-84"><span class="mw-cite-backlink"><b><a href="#cite_ref-84">^</a></b></span> <span class="reference-text">The "first to market" advantage can be summarized as "In 1972, computer designer Seymour Cray left CDC and formed a new company" as noted in Getting Up to Speed: The Future of Supercomputing, 2005, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0309165512" title="Special:BookSources/0309165512">0309165512</a>, by National Research Council, Division on Engineering and Physical Sciences, Computer Science and Telecommunications Board</span> </li> <li id="cite_note-85"><span class="mw-cite-backlink"><b><a href="#cite_ref-85">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20231209132724/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4331.html">"4331 Processor"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4331.html">the original</a> on 2023-12-09.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=4331+Processor&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP4331.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-86"><span class="mw-cite-backlink"><b><a href="#cite_ref-86">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719223403/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4341.html">"4341 Processor"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4341.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=4341+Processor&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP4341.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-87"><span class="mw-cite-backlink"><b><a href="#cite_ref-87">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20201021214611/https://www.ibm.com/ibm/history/exhibits/dpd50/dpd50_chronology5.html">"IBM Archives: DPD chronology - page 5"</a>. <i><a href="/wiki/IBM" title="IBM">IBM</a></i>. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/dpd50/dpd50_chronology5.html">the original</a> on 2020-10-21.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM&rft.atitle=IBM+Archives%3A+DPD+chronology+-+page+5&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fdpd50%2Fdpd50_chronology5.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM.4361-88"><span class="mw-cite-backlink">^ <a href="#cite_ref-IBM.4361_88-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-IBM.4361_88-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230914064000/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4361.html">"4361 Processor"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4361.html">the original</a> on 2023-09-14.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=4361+Processor&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP4361.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-IBM.4381-89"><span class="mw-cite-backlink">^ <a href="#cite_ref-IBM.4381_89-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-IBM.4381_89-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230719145726/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4381.html">"4381 Processor"</a>. <i>IBM Archives</i>. IBM. 23 January 2003. Archived from <a rel="nofollow" class="external text" href="https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4381.html">the original</a> on 2023-07-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IBM+Archives&rft.atitle=4381+Processor&rft.date=2003-01-23&rft_id=https%3A%2F%2Fwww.ibm.com%2Fibm%2Fhistory%2Fexhibits%2Fmainframe%2Fmainframe_PP4381.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-92"><span class="mw-cite-backlink"><b><a href="#cite_ref-92">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS186-178&open&cm_mmc=5733-_-n-_-vrm_newsletter-_-10207_134134&cmibm_em=dm:0:12046832">"IBM 9370 INFORMATION SYSTEM OVERVIEW"</a>. IBM. October 7, 1986.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=IBM+9370+INFORMATION+SYSTEM+OVERVIEW&rft.pub=IBM&rft.date=1986-10-07&rft_id=http%3A%2F%2Fwww.ibm.com%2Fcommon%2Fssi%2Fcgi-bin%2Fssialias%3Fsubtype%3Dca%26infotype%3Dan%26appname%3DiSource%26supplier%3D897%26letternum%3DENUS186-178%26open%26cm_mmc%3D5733-_-n-_-vrm_newsletter-_-10207_134134%26cmibm_em%3Ddm%3A0%3A12046832&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-93"><span class="mw-cite-backlink"><b><a href="#cite_ref-93">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://inspirehep.net/record/312767/files/ssc-n-691.pdf">"Report Of The SSC Computer Planning Committee"</a> <span class="cs1-format">(PDF)</span>. January 1990. chapter 5.4, "SUMMARY OF RELATIVE STRENGTH OF DEC/VMS AND IBM/VM".</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Report+Of+The+SSC+Computer+Planning+Committee&rft.pages=chapter+5.4%2C+%22SUMMARY+OF+RELATIVE+STRENGTH+OF+DEC%2FVMS+AND+IBM%2FVM%22&rft.date=1990-01&rft_id=http%3A%2F%2Finspirehep.net%2Frecord%2F312767%2Ffiles%2Fssc-n-691.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-94"><span class="mw-cite-backlink"><b><a href="#cite_ref-94">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDavid_E._Sanger1988" class="citation news cs1">David E. Sanger (January 3, 1988). <a rel="nofollow" class="external text" href="https://www.nytimes.com/1988/01/03/business/the-moment-of-truth-for-big-blue.html">"The Moment of Truth for Big Blue"</a>. <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i>. <q>appears to be slaying precious few Vaxes</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=The+Moment+of+Truth+for+Big+Blue&rft.date=1988-01-03&rft.au=David+E.+Sanger&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1988%2F01%2F03%2Fbusiness%2Fthe-moment-of-truth-for-big-blue.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-95"><span class="mw-cite-backlink"><b><a href="#cite_ref-95">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDavid_S._Bennahum1997" class="citation magazine cs1">David S. Bennahum (November 1997). <a rel="nofollow" class="external text" href="https://www.wired.com/1997/11/heartof">"Heart of Darkness"</a>. <i><a href="/wiki/Wired_(magazine)" title="Wired (magazine)">Wired</a></i>. <q>from 1967 to 1972, it put in place a massive industrial complex to reverse-engineer, copy, and produce IBM mainframes and DEC minicomputers... Once a computer was reduced to its constituent bits on both a software and hardware level, industrial management designed a manufacturing process to replicate the machine... a clone of the IBM 360/40 in 1970, a Cold War coup. Later, he worked on duplicating the IBM 370</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Wired&rft.atitle=Heart+of+Darkness&rft.date=1997-11&rft.au=David+S.+Bennahum&rft_id=https%3A%2F%2Fwww.wired.com%2F1997%2F11%2Fheartof&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-96"><span class="mw-cite-backlink"><b><a href="#cite_ref-96">^</a></b></span> <span class="reference-text">Re the 370 (followup to 360/40 clone): <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMichael_Weisskopf1985" class="citation news cs1">Michael Weisskopf (September 24, 1985). <a rel="nofollow" class="external text" href="https://www.washingtonpost.com/archive/politics/1985/09/24/soviet-radar-allegedly-stolen-from-us/3a754179-c337-4d60-8471-2e7b1d76f6bd/?noredirect=on">"Soviet Radar Allegedly Stolen From U.S."</a> <i><a href="/wiki/The_Washington_Post" title="The Washington Post">The Washington Post</a></i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Washington+Post&rft.atitle=Soviet+Radar+Allegedly+Stolen+From+U.S.&rft.date=1985-09-24&rft.au=Michael+Weisskopf&rft_id=https%3A%2F%2Fwww.washingtonpost.com%2Farchive%2Fpolitics%2F1985%2F09%2F24%2Fsoviet-radar-allegedly-stolen-from-us%2F3a754179-c337-4d60-8471-2e7b1d76f6bd%2F%3Fnoredirect%3Don&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-97"><span class="mw-cite-backlink"><b><a href="#cite_ref-97">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDavid_E._Sanger1984" class="citation news cs1">David E. Sanger (February 5, 1984). <a rel="nofollow" class="external text" href="https://www.nytimes.com/1984/02/05/business/bailing-out-of-the-mainframe-industry.html">"Bailing Out Of The Mainframe Industry"</a>. <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i>. <q>an acronym for Burroughs, ... and Honeywell</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=Bailing+Out+Of+The+Mainframe+Industry&rft.date=1984-02-05&rft.au=David+E.+Sanger&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1984%2F02%2F05%2Fbusiness%2Fbailing-out-of-the-mainframe-industry.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-98"><span class="mw-cite-backlink"><b><a href="#cite_ref-98">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMichalopoulos1978" class="citation journal cs1">Michalopoulos, D. A. (June 1978). <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/document/1647006">"Microprocessor-based minicomputer runs IBM 370 software"</a>. <i>Computer</i>. <b>11</b> (6). IEEE: 87–90. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FC-M.1978.218231">10.1109/C-M.1978.218231</a><span class="reference-accessdate">. Retrieved <span class="nowrap">July 1,</span> 2021</span>. <q>The plug-compatible CPU is the conception of Dr. Jared A. Anderson and his associates at Two Pi Corp., ..</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Computer&rft.atitle=Microprocessor-based+minicomputer+runs+IBM+370+software&rft.volume=11&rft.issue=6&rft.pages=87-90&rft.date=1978-06&rft_id=info%3Adoi%2F10.1109%2FC-M.1978.218231&rft.aulast=Michalopoulos&rft.aufirst=D.+A.&rft_id=https%3A%2F%2Fieeexplore.ieee.org%2Fdocument%2F1647006&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES3704-10–4-11[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage83_Assignment_of_Control-Register_Fields]-99"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES3704-10–4-11[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage83_Assignment_of_Control-Register_Fields]_99-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 4-10–4-11, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=83">Assignment of Control-Register Fields</a>.</span> </li> <li id="cite_note-FOOTNOTES3704-8_–&#32,_4–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage81_Program-Status_Word_Format_in_BC_Mode]-100"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES3704-8_–&#32,_4–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage81_Program-Status_Word_Format_in_BC_Mode]_100-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 4-8 –&#32, 4–9, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=81">Program-Status Word Format in BC Mode</a>.</span> </li> <li id="cite_note-FOOTNOTES3706-3_–&#32,_6–5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage154_Interruption_Action]-101"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES3706-3_–&#32,_6–5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage154_Interruption_Action]_101-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 6-3 –&#32, 6–5, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=154">Interruption Action</a>.</span> </li> <li id="cite_note-FOOTNOTES3706-7_–&#32,_6–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage158_Instruction-Length_Code]-102"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES3706-7_–&#32,_6–9[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage158_Instruction-Length_Code]_102-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 6-7 –&#32, 6–9, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=158">Instruction-Length Code</a>.</span> </li> <li id="cite_note-FOOTNOTES3704-6_–&#32,_4–7[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage79_Program-Status_Word_Format_in_EC_Mode]-103"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES3704-6_–&#32,_4–7[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage79_Program-Status_Word_Format_in_EC_Mode]_103-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 4-6 –&#32, 4–7, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=79">Program-Status Word Format in EC Mode</a>.</span> </li> <li id="cite_note-FOOTNOTES370-104"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES370_104-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>.</span> </li> <li id="cite_note-FOOTNOTES3701-1_–&#32,_1–4[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage16_Chapter_1_Introduction]-105"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES3701-1_–&#32,_1–4[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage16_Chapter_1_Introduction]_105-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, pp. 1-1 –&#32, 1–4, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=16">Chapter 1 Introduction</a>.</span> </li> <li id="cite_note-106"><span class="mw-cite-backlink"><b><a href="#cite_ref-106">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://www.computinghistory.org.uk/downloads/12265"><i>IBM System/370 Extended Facility and ECPS:MVS</i></a> (Second ed.). IBM. November 1980. GA22-7072-1.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+System%2F370+Extended+Facility+and+ECPS%3AMVS&rft.edition=Second&rft.pub=IBM&rft.date=1980-11&rft_id=http%3A%2F%2Fwww.computinghistory.org.uk%2Fdownloads%2F12265&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-107"><span class="mw-cite-backlink"><b><a href="#cite_ref-107">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/VM/370/GA22-7074-0_Virtual-Machine_Assist_and_Shadow-Table-Bypass_Assist_May80.pdf"><i>Virtual-Machine Assist and Shadow-Table-Bypass Assist</i></a> <span class="cs1-format">(PDF)</span> (First ed.). IBM. May 1980. GA22-7074-0<span class="reference-accessdate">. Retrieved <span class="nowrap">2024-09-19</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Virtual-Machine+Assist+and+Shadow-Table-Bypass+Assist&rft.edition=First&rft.pub=IBM&rft.date=1980-05&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F370%2FVM%2F370%2FGA22-7074-0_Virtual-Machine_Assist_and_Shadow-Table-Bypass_Assist_May80.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-108"><span class="mw-cite-backlink"><b><a href="#cite_ref-108">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/4300/GA22-7070-1_4300_Processors_PrincOps_ECPS_VSE_Mode_Sep80.pdf"><i>IBM 4300 Processors Principles of Operation for ECPS:VSE Mode</i></a> <span class="cs1-format">(PDF)</span> (Second ed.). IBM. September 1980. GA22-7070-1.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+4300+Processors+Principles+of+Operation+for+ECPS%3AVSE+Mode&rft.edition=Second&rft.pub=IBM&rft.date=1980-09&rft_id=http%3A%2F%2Fbitsavers.org%2Fpdf%2Fibm%2F4300%2FGA22-7070-1_4300_Processors_PrincOps_ECPS_VSE_Mode_Sep80.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES390-ESA1-13_–&#32,_1–14[httppublibzboulderibmcomepubspdfdz9ar008pdfpage45_Section_1.3.2.2_Problem-State_Compatibility]-109"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES390-ESA1-13_–&#32,_1–14[httppublibzboulderibmcomepubspdfdz9ar008pdfpage45_Section_1.3.2.2_Problem-State_Compatibility]_109-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS390-ESA">S390-ESA</a>, pp. 1-13 –&#32, 1–14, <a rel="nofollow" class="external text" href="http://publibz.boulder.ibm.com/epubs/pdf/dz9ar008.pdf#page=45">Section 1.3.2.2 Problem-State Compatibility</a>.</span> </li> <li id="cite_note-110"><span class="mw-cite-backlink"><b><a href="#cite_ref-110">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://gcc.gnu.org/gcc-3.4/changes.html#obsolete_systems">"Removed architectures and systems removed from GCC 3.4"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Removed+architectures+and+systems+removed+from+GCC+3.4&rft_id=https%3A%2F%2Fgcc.gnu.org%2Fgcc-3.4%2Fchanges.html%23obsolete_systems&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-111"><span class="mw-cite-backlink"><b><a href="#cite_ref-111">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://gccmvs.sourceforge.net">"GCCMVS (GCC 3.2.3 for S/370)"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=GCCMVS+%28GCC+3.2.3+for+S%2F370%29&rft_id=http%3A%2F%2Fgccmvs.sourceforge.net&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTES37013-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage356_Programming_Note]-112"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTES37013-5[httpbitsaversorgpdfibm370princOpsGA22-7000-10_370_Principles_of_Operation_Sep87pdfpage356_Programming_Note]_112-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFS370">S370</a>, p. 13-5, <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/370/princOps/GA22-7000-10_370_Principles_of_Operation_Sep87.pdf#page=356">Programming Note</a>.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=39" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPrasad1989" class="citation book cs1">Prasad, N.S. (1989). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/ibmmainframesarc00pras"><i>IBM Mainframes</i></a></span>. McGraw-Hill. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0070506868" title="Special:BookSources/0070506868"><bdi>0070506868</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=IBM+Mainframes&rft.pub=McGraw-Hill&rft.date=1989&rft.isbn=0070506868&rft.aulast=Prasad&rft.aufirst=N.S.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fibmmainframesarc00pras&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIBM+System%2F370" class="Z3988"></span> — Chapter 4 (pp. 111–166) describes the System/370 architecture; Chapter 5 (pp. 167–206) describes the System/370 Extended Architecture.</li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=IBM_System/370&action=edit&section=40" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.hercules-390.eu/">Hercules System/370 Emulator</a> A software implementation of IBM System/370</li></ul> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="IBM_System/370" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:IBM_System/370_line" title="Template:IBM System/370 line"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:IBM_System/370_line" title="Template talk:IBM System/370 line"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:IBM_System/370_line" title="Special:EditPage/Template:IBM System/370 line"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="IBM_System/370" style="font-size:114%;margin:0 4em"><a class="mw-selflink selflink">IBM System/370</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Models</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">System/370<br />(1970–1977)</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IBM_System/370_Model_115" title="IBM System/370 Model 115">Model 115</a></li> <li><a href="/w/index.php?title=IBM_System/370_Model_125&action=edit&redlink=1" class="new" title="IBM System/370 Model 125 (page does not exist)">Model 125</a></li> <li><a href="/wiki/IBM_System/370_Model_135" title="IBM System/370 Model 135">Model 135</a></li> <li><a href="/w/index.php?title=IBM_System/370_Model_138&action=edit&redlink=1" class="new" title="IBM System/370 Model 138 (page does not exist)">Model 138</a></li> <li><a href="/wiki/IBM_System/370_Model_145" title="IBM System/370 Model 145">Model 145</a></li> <li><a href="/wiki/IBM_System/370_Model_148" title="IBM System/370 Model 148">Model 148</a></li> <li><a href="/wiki/IBM_System/370_Model_155" title="IBM System/370 Model 155">Model 155</a></li> <li><a href="/w/index.php?title=IBM_System/370_Model_158&action=edit&redlink=1" class="new" title="IBM System/370 Model 158 (page does not exist)">Model 158</a></li> <li><a href="/wiki/IBM_System/370_Model_165" title="IBM System/370 Model 165">Model 165</a></li> <li><a href="/wiki/IBM_System/370_Model_168" title="IBM System/370 Model 168">Model 168</a></li> <li><a href="/wiki/IBM_System/370_Model_195" class="mw-redirect" title="IBM System/370 Model 195">Model 195</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/IBM_30XX_mainframe_lines" title="IBM 30XX mainframe lines">30XX</a><br />(1977–1990)</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IBM_303X" title="IBM 303X">303X series</a></li> <li><a href="/wiki/IBM_308X" title="IBM 308X">308X series</a></li> <li><a href="/wiki/IBM_3090" title="IBM 3090">3090</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Low-end</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IBM_4300" title="IBM 4300">43xx models</a></li> <li><a href="/wiki/IBM_9370" title="IBM 9370">9370 models</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Peripherals</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IBM_270x" title="IBM 270x">270x communications controllers</a></li> <li><a href="/wiki/IBM_3705_Communications_Controller" title="IBM 3705 Communications Controller">3705 Communications Controller</a></li> <li><a href="/wiki/IBM_2540" title="IBM 2540">2540 punched-card reader–writer</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Software</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/DOS/360_and_successors" title="DOS/360 and successors">DOS/360 and successors</a></li> <li><a href="/wiki/OS/360_and_successors" title="OS/360 and successors">OS/360 and successors</a> <ul><li><a href="/wiki/OS/VS1" title="OS/VS1">OS/VS1</a></li></ul></li> <li><a href="/wiki/TSS_(operating_system)" title="TSS (operating system)">TSS/370</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IBM_Basic_Assembly_Language_and_successors" class="mw-redirect" title="IBM Basic Assembly Language and successors">Basic Assembly Language and successors</a></li> <li><a href="/wiki/Bus_and_Tag" title="Bus and Tag">Bus and Tag</a></li> <li><a href="/wiki/Channel_I/O" title="Channel I/O">Channel I/O</a></li> <li><a href="/wiki/ES_EVM" title="ES EVM">ES EVM</a></li> <li><a href="/wiki/IBM_hexadecimal_floating-point" title="IBM hexadecimal floating-point">Hexadecimal floating-point</a></li> <li><a href="/wiki/Hercules_(emulator)" title="Hercules (emulator)">Hercules</a></li> <li><a href="/wiki/Language_for_Systems_Development" title="Language for Systems Development">Language for Systems Development</a></li> <li><a href="/wiki/PC-based_IBM_mainframe-compatible_systems" title="PC-based IBM mainframe-compatible systems">PC-based IBM mainframe-compatible systems</a></li> <li><a href="/wiki/Program_status_word" title="Program status word">Program status word</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><a href="/wiki/IBM_System/360" title="IBM System/360">System/360</a></li> <li><a class="mw-selflink selflink">System/370</a></li> <li><a href="/wiki/IBM_System/390" title="IBM System/390">IBM System/390</a></li> <li><a href="/wiki/IBM_Z#IBM_zSeries_family" title="IBM Z">IBM zSeries</a></li> <li><a href="/wiki/IBM_System_z9" title="IBM System z9">System z9</a></li> <li><a href="/wiki/IBM_System_z10" title="IBM System z10">System z10</a></li> <li><a href="/wiki/IBM_Z#IBM_zEnterprise_System" title="IBM Z">IBM zEnterprise System</a></li> <li><a href="/wiki/IBM_Z" title="IBM Z">IBM Z</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=IBM_System/370&oldid=1259634430">https://en.wikipedia.org/w/index.php?title=IBM_System/370&oldid=1259634430</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" 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