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<div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Massbus peripherals</span> </div> </a> <button aria-controls="toc-Massbus_peripherals-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 Massbus peripherals subsection</span> </button> <ul id="toc-Massbus_peripherals-sublist" class="vector-toc-list"> <li id="toc-Disk" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Disk"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Disk</span> </div> </a> <ul id="toc-Disk-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Tape" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Tape"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Tape</span> </div> </a> <ul id="toc-Tape-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Massbus_CPU_interfaces" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Massbus_CPU_interfaces"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Massbus CPU interfaces</span> </div> </a> <ul id="toc-Massbus_CPU_interfaces-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>References</span> </div> </a> <ul id="toc-References-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 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</div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">DEC high performance interface</div> <p>The <b>Massbus</b> is a high-performance <a href="/wiki/Computer" title="Computer">computer</a> <a href="/wiki/Input/output" title="Input/output">input/output</a> <a href="/wiki/Bus_(computing)" title="Bus (computing)">bus</a> designed in the 1970s by <a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> (DEC). The architecture development was sponsored by Gordon Bell and John Levy was the principal architect. </p><p>The bus was used by Digital to interconnect its highest-performance computers with <a href="/wiki/Magnetic_disk" class="mw-redirect" title="Magnetic disk">magnetic disk</a> and <a href="/wiki/Magnetic_tape" title="Magnetic tape">magnetic tape</a> storage equipment. The use of a common bus was intended to allow a single controller design to handle multiple peripheral models,<sup id="cite_ref-dec-std-159_1-0" class="reference"><a href="#cite_note-dec-std-159-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 7.0">: 7.0 </span></sup> and allowed the <a href="/wiki/PDP-10" title="PDP-10">PDP-10</a>, <a href="/wiki/PDP-11" title="PDP-11">PDP-11</a>, and <a href="/wiki/VAX" title="VAX">VAX</a> computer families to share a common set of peripherals. At the time there were multiple <a href="/wiki/Operating_system" title="Operating system">operating systems</a> for each of the 16-bit, 32-bit, and 36-bit computer lines. The 18-bit <a href="/wiki/PDP-15" title="PDP-15">PDP-15</a>/40 connected to Massbus peripherals via a PDP-11 front end. An engineering goal was to reduce the need for a new driver per peripheral per operating system per computer family. Also, a major technical goal was to place any magnetic technology changes (data separators) into the storage device rather than in the CPU-attached controller. Thus the CPU I/O or memory bus to Massbus adapter needed no changes for multiple generations of storage technology. </p><p>A business objective was to provide a subsystem entry price well below that of IBM storage subsystems which used large and expensive controllers unique to each storage technology and processor architecture and were optimized for connecting large numbers of storage devices. </p><p>The first Massbus device was the RP04, based on <a href="/wiki/Sperry_Univac" class="mw-redirect" title="Sperry Univac">Sperry Univac</a> Information Storage Systems's (ISS) clone of the IBM 3330.<sup id="cite_ref-EK-RP04-IN-001_2-0" class="reference"><a href="#cite_note-EK-RP04-IN-001-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> Subsequently, DEC offered the RP05 and RP06, based on <a href="/wiki/Memorex" title="Memorex">Memorex</a>'s 3330 clone. Memorex modified the IBM compatible interface to DEC requirements and moved the data separator electronics into the drive. DEC designed the rest which was mounted in the "bustle" attached to the drive. This set the pattern for future improvements of disk technology to double density 3330, CDC SMD drives, and then "Winchester" technology. Drives were supplied by ISS/Univac, Memorex, and Control Data. Multiple generations of tape technology and performance were also Massbus connected although the architecture was a Master Massbus drive and slave tape drives. DEC also developed the Massbus RS03/04, a head per track disk drive for high performance swapping. The last Massbus disk drive was the DEC designed RM80 as DEC shifted to internal development of large disks. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Logical_implementation">Logical implementation</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massbus&action=edit&section=1" title="Edit section: Logical implementation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The bus is logically implemented as two separate sections: </p> <ul><li>An asynchronous control bus used to access <a href="/wiki/Memory-mapped_I/O" class="mw-redirect" title="Memory-mapped I/O">memory-mapped I/O</a> registers in the individual storage devices,<sup id="cite_ref-dec-std-159_1-1" class="reference"><a href="#cite_note-dec-std-159-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 8.0">: 8.0 </span></sup> and</li> <li>A high-speed, synchronous data bus that is used to carry the actual data transfers between the storage devices and the host bus adapter.<sup id="cite_ref-dec-std-159_1-2" class="reference"><a href="#cite_note-dec-std-159-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 8.0">: 8.0 </span></sup> The data bus is 18 bits wide plus parity.<sup id="cite_ref-dec-std-159_1-3" class="reference"><a href="#cite_note-dec-std-159-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 34.0">: 34.0 </span></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="Massbus_peripherals">Massbus peripherals</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massbus&action=edit&section=2" title="Edit section: Massbus peripherals"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Disk">Disk</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massbus&action=edit&section=3" title="Edit section: Disk"><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:LCM_-_DEC_RP06_drives_-_02.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/55/LCM_-_DEC_RP06_drives_-_02.jpg/220px-LCM_-_DEC_RP06_drives_-_02.jpg" decoding="async" width="220" height="146" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/55/LCM_-_DEC_RP06_drives_-_02.jpg/330px-LCM_-_DEC_RP06_drives_-_02.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/55/LCM_-_DEC_RP06_drives_-_02.jpg/440px-LCM_-_DEC_RP06_drives_-_02.jpg 2x" data-file-width="4288" data-file-height="2848" /></a><figcaption>RP06 disk drive, with cover for removable pack atop its sliding glass door</figcaption></figure> <ul><li>RP04 88 MB <a href="/wiki/Sperry_Univac" class="mw-redirect" title="Sperry Univac">Sperry Univac</a> Information Storage Systems pack-loaded (removable) disk drive<sup id="cite_ref-EK-RP04-IN-001_2-1" class="reference"><a href="#cite_note-EK-RP04-IN-001-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></li> <li>RP05/RP06 100/200 MB <a href="/wiki/Memorex" title="Memorex">Memorex</a> 677-51/677-01 pack-loaded (removable) disk drive<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></li></ul> <dl><dd><dl><dd>The RP04<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> and RP06<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> disks were comparable to the 100 MB <a href="/wiki/IBM_3330" class="mw-redirect" title="IBM 3330">IBM 3330</a> Mod I and IBM's 200 MB Model 11 thereof. The 100 MB RP05 was designated as "high performance" compared to the RP04.<sup id="cite_ref-SitePrep20_7-0" class="reference"><a href="#cite_note-SitePrep20-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></dd></dl></dd></dl> <ul><li>RP20 - 1.2Gb (non-removable)<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup></li> <li>RMxx disk drives: <ul><li>RM02/03/05/80<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></li></ul></li> <li>RS03/RS04 head per track disks</li></ul> <div class="mw-heading mw-heading3"><h3 id="Tape">Tape</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massbus&action=edit&section=4" title="Edit section: Tape"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>TU45 9 track, capable of 800 BPI and 1600 BPI; 120,000 bytes/second<sup id="cite_ref-SitePrep20_7-1" class="reference"><a href="#cite_note-SitePrep20-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></li> <li>TU78/TA78 6250 GCR<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> The 1600/6250 BPI TU78 uses DEC's Massbus, whereas the TA78 uses the <a href="/wiki/VMScluster" title="VMScluster">HSC50</a> <a href="/wiki/Mass_Storage_Control_Protocol" title="Mass Storage Control Protocol">controller</a>.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="Massbus_CPU_interfaces">Massbus CPU interfaces</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massbus&action=edit&section=5" title="Edit section: Massbus CPU interfaces"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>RH11—To the PDP-11's <a href="/wiki/Unibus" title="Unibus">Unibus</a><sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup></li> <li>RH750—To the VAX-11/75x bus<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup></li></ul> <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=Massbus&action=edit&section=6" title="Edit section: References"><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"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-dec-std-159-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-dec-std-159_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-dec-std-159_1-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-dec-std-159_1-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-dec-std-159_1-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><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 class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/dec/standards/DEC_STD_159_Massbus_Specificaton.pdf">"Massbus Specification"</a> <span class="cs1-format">(PDF)</span>. DEC STD 159.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Massbus+Specification&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fdec%2Fstandards%2FDEC_STD_159_Massbus_Specificaton.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-EK-RP04-IN-001-2"><span class="mw-cite-backlink">^ <a href="#cite_ref-EK-RP04-IN-001_2-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-EK-RP04-IN-001_2-1"><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://vaxhaven.com/images/c/cd/EK-RP04-IN-001.pdf"><i>RP04 Disk Drive Installation Manual</i></a> <span class="cs1-format">(PDF)</span> (1st ed.). <a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a>. March 1975. p. 1-1. EK-RP04-IN-001. <q>The RP04 (Figure 1-2) consists of a 733 DEC Disk Storage Drive (manufactured by Information Storage Systems) and a Device Control Logic (DCL) unit (Figure 1-3) (manufactured by Digital Equipment Corporation).</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=RP04+Disk+Drive+Installation+Manual&rft.pages=1%26%2345%3B1&rft.edition=1st&rft.pub=Digital+Equipment+Corporation&rft.date=1975-03&rft_id=http%3A%2F%2Fvaxhaven.com%2Fimages%2Fc%2Fcd%2FEK-RP04-IN-001.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <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="https://www.computerhistory.org/collections/catalog/102733625">"RP06 disk drive"</a>. Computer History Museum.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=RP06+disk+drive&rft.pub=Computer+History+Museum&rft_id=https%3A%2F%2Fwww.computerhistory.org%2Fcollections%2Fcatalog%2F102733625&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</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://bitsavers.org/www.computer.museum.uq.edu.au/pdf/EK-RP056-IN-001%20RP05%20&%20RP06%20Disk%20Drive%20Installation%20Manual.pdf">"RP05/RP06 disk drive installation manual"</a> <span class="cs1-format">(PDF)</span>. Digital Equipment Corporation. EK-RP056-IN-001.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=RP05%2FRP06+disk+drive+installation+manual&rft.pub=Digital+Equipment+Corporation&rft_id=http%3A%2F%2Fbitsavers.org%2Fwww.computer.museum.uq.edu.au%2Fpdf%2FEK-RP056-IN-001%2520RP05%2520%26%2520RP06%2520Disk%2520Drive%2520Installation%2520Manual.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</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.columbia.edu/cu/computinghistory/rp04.html">"The DEC RP04 Disk Drive"</a>. <i>columbia.edu</i>. 1975<span class="reference-accessdate">. Retrieved <span class="nowrap">2024-06-09</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=columbia.edu&rft.atitle=The+DEC+RP04+Disk+Drive&rft.date=1975&rft_id=http%3A%2F%2Fwww.columbia.edu%2Fcu%2Fcomputinghistory%2Frp04.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</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.columbia.edu/cu/computinghistory/rp06.html">"The DEC RP06 Disk Drive"</a>. <i>columbia.edu</i>. 1977<span class="reference-accessdate">. Retrieved <span class="nowrap">2024-06-09</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=columbia.edu&rft.atitle=The+DEC+RP06+Disk+Drive&rft.date=1977&rft_id=http%3A%2F%2Fwww.columbia.edu%2Fcu%2Fcomputinghistory%2Frp06.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-SitePrep20-7"><span class="mw-cite-backlink">^ <a href="#cite_ref-SitePrep20_7-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-SitePrep20_7-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">EK-DEC20-SP-002 <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><i>DECSYSTEM-20 Site Preparation Guide</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=DECSYSTEM-20+Site+Preparation+Guide&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</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/20220324033707/https://www.inwap.com/pdp10/hardware/disks-1981.html">"DECsystem-10 Technical Summary"</a>. <i>inwap.com</i>. 1981. Archived from <a rel="nofollow" class="external text" href="https://www.inwap.com/pdp10/hardware/disks-1981.html">the original</a> on 2022-03-24.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=inwap.com&rft.atitle=DECsystem-10+Technical+Summary&rft.date=1981&rft_id=https%3A%2F%2Fwww.inwap.com%2Fpdp10%2Fhardware%2Fdisks-1981.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</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.bitsavers.org/pdf/dec/disc/rm05/EK-RMADA-TD-001_Oct80.pdf"><i>RM MASSBUS Adapter Technical Description Manual</i></a> <span class="cs1-format">(PDF)</span>. Digital Equipment Corporation. October 1980. p. IV.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=RM+MASSBUS+Adapter+Technical+Description+Manual&rft.pages=IV&rft.pub=Digital+Equipment+Corporation&rft.date=1980-10&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fdec%2Fdisc%2Frm05%2FEK-RMADA-TD-001_Oct80.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text">top density</span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</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.bitsavers.org/pdf/dec/magtape/ta78/EK-0TA78-SV-001_TA78service.pdf">"TA78 Magnetic Tape Drive Service Manual"</a> <span class="cs1-format">(PDF)</span>. Digital Equipment Corporation. 1984. EK-0TA78-SV-001.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=TA78+Magnetic+Tape+Drive+Service+Manual&rft.pub=Digital+Equipment+Corporation&rft.date=1984&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fdec%2Fmagtape%2Fta78%2FEK-0TA78-SV-001_TA78service.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</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://support.hpe.com/hpsc/doc/public/display?docId=emr_na-c00336096">"DIGITAL TU78 Reel-to-Reel Tape Drive: Overview"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=DIGITAL+TU78+Reel-to-Reel+Tape+Drive%3A+Overview&rft_id=https%3A%2F%2Fsupport.hpe.com%2Fhpsc%2Fdoc%2Fpublic%2Fdisplay%3FdocId%3Demr_na-c00336096&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><i>Storage Systems: TA78 & TU78</i>. <a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a>. <q>ORDER CODE ED-23908-18</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Storage+Systems%3A+TA78+%26+TU78&rft.pub=Digital+Equipment+Corporation&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBellMudgeMcNamara1979" class="citation book cs1"><a href="/wiki/Gordon_Bell" title="Gordon Bell">Bell, C. Gordon</a>; Mudge, J. Craig; McNamara, John E. (August 1979). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=SDOoBQAAQBAJ&dq=RH11+massbus&pg=PA278"><i>Computer Engineering: A DEC View of Hardware Systems Design</i></a>. Digital Press. p. 278. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-932376-00-2" title="Special:BookSources/0-932376-00-2"><bdi>0-932376-00-2</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Computer+Engineering%3A+A+DEC+View+of+Hardware+Systems+Design&rft.pages=278&rft.pub=Digital+Press&rft.date=1979-08&rft.isbn=0-932376-00-2&rft.aulast=Bell&rft.aufirst=C.+Gordon&rft.au=Mudge%2C+J.+Craig&rft.au=McNamara%2C+John+E.&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DSDOoBQAAQBAJ%26dq%3DRH11%2Bmassbus%26pg%3DPA278&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://manx-docs.org/details.php/1,5561">"RH750 Massbus Adapter Technical Description"</a>. <i>manx-docs.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2024-06-09</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=manx-docs.org&rft.atitle=RH750+Massbus+Adapter+Technical+Description&rft_id=https%3A%2F%2Fmanx-docs.org%2Fdetails.php%2F1%2C5561&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMassbus" class="Z3988"></span></span> </li> </ol></div></div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol 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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:Digital_Equipment_Corporation" title="Template:Digital Equipment Corporation"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Digital_Equipment_Corporation" title="Template talk:Digital Equipment Corporation"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Digital_Equipment_Corporation" title="Special:EditPage/Template:Digital Equipment Corporation"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Digital_Equipment_Corporation" style="font-size:114%;margin:0 4em"><a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Key people</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/Ken_Olsen" title="Ken Olsen">Ken Olsen</a> (founder and CEO, 1957–1992)</li> <li><a href="/wiki/Harlan_Anderson" title="Harlan Anderson">Harlan Anderson</a> (co-founder)</li> <li><a href="/wiki/Gordon_Bell" title="Gordon Bell">Gordon Bell</a> (VP of engineering)</li> <li><a href="/wiki/Robert_Palmer_(computer_businessman)" title="Robert Palmer (computer businessman)">Robert Palmer</a> (CEO, 1992–1998)</li></ul> </div></td><td class="noviewer navbox-image" rowspan="9" style="width:1px;padding:0 0 0 2px"><div><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Digital_Equipment_Corporation_1993_logo.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Digital_Equipment_Corporation_1993_logo.svg/110px-Digital_Equipment_Corporation_1993_logo.svg.png" decoding="async" width="110" height="33" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Digital_Equipment_Corporation_1993_logo.svg/165px-Digital_Equipment_Corporation_1993_logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/90/Digital_Equipment_Corporation_1993_logo.svg/220px-Digital_Equipment_Corporation_1993_logo.svg.png 2x" data-file-width="3124" data-file-height="938" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Instruction_set_architecture" title="Instruction set architecture">Instruction set<br />architectures</a>,<br /><a href="/wiki/Processor_(computing)" title="Processor (computing)">processors</a></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%"><a href="/wiki/PDP-11_architecture" title="PDP-11 architecture">PDP-11</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>LSI-11</li> <li>F-11</li> <li><a href="/wiki/DEC_T-11" title="DEC T-11">T-11</a></li> <li><a href="/wiki/DEC_J-11" title="DEC J-11">J-11</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/VAX" title="VAX">VAX</a></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/DEC_V-11" title="DEC V-11">V-11</a></li> <li><a href="/wiki/MicroVAX_78032" title="MicroVAX 78032">MicroVAX 78032</a></li> <li><a href="/wiki/CVAX" title="CVAX">CVAX</a> <ul><li><a href="/wiki/CVAX#SOC" title="CVAX">SOC</a></li></ul></li> <li><a href="/wiki/Rigel_(microprocessor)" title="Rigel (microprocessor)">Rigel</a> <ul><li><a href="/wiki/Rigel_(microprocessor)#Mariah" title="Rigel (microprocessor)">Mariah</a></li></ul></li> <li><a href="/wiki/NVAX" title="NVAX">NVAX</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/DEC_Alpha" title="DEC Alpha">Alpha</a></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/Alpha_21064" title="Alpha 21064">Alpha 21064</a> <ul><li><a href="/wiki/Alpha_21064#Alpha_21066" title="Alpha 21064">21066</a></li> <li><a href="/wiki/Alpha_21064#Alpha_21068" title="Alpha 21064">21068</a></li></ul></li> <li><a href="/wiki/Alpha_21164" title="Alpha 21164">Alpha 21164</a> (<a href="/wiki/Alpha_21164#Alpha_21164PC_(PCA56)" title="Alpha 21164">21164PC</a>)</li> <li><a href="/wiki/Alpha_21264" title="Alpha 21264">Alpha 21264</a></li> <li><a href="/wiki/Alpha_21364" title="Alpha 21364">Alpha 21364</a></li> <li><a href="/wiki/Alpha_21464" title="Alpha 21464">Alpha 21464</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</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/DEC_PRISM" title="DEC PRISM">MicroPRISM</a></li> <li><a href="/wiki/StrongARM" title="StrongARM">StrongARM</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Computer_terminal" title="Computer terminal">Computer<br />terminals</a></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/VT05" title="VT05">VT05</a> (1970)</li> <li><a href="/wiki/DEC_GT40" title="DEC GT40">GT40</a> (1972)</li> <li><a href="/wiki/VT52" title="VT52">VT50/VT52</a> (1975)</li> <li><a href="/wiki/VT55" class="mw-redirect" title="VT55">VT55</a></li> <li><a href="/wiki/VT62" class="mw-redirect" title="VT62">VT62</a></li> <li><a href="/wiki/VT100" title="VT100">VT100</a> (1978)</li> <li><a href="/wiki/VT101" class="mw-redirect" title="VT101">VT101</a></li> <li><a href="/wiki/VT102" class="mw-redirect" title="VT102">VT102</a></li> <li><a href="/wiki/VT103" class="mw-redirect" title="VT103">VT103</a></li> <li><a href="/wiki/VT105" class="mw-redirect" title="VT105">VT105</a></li> <li><a href="/wiki/VT131" class="mw-redirect" title="VT131">VT131</a></li> <li><a href="/wiki/VT180" title="VT180">VT180</a></li> <li><a href="/wiki/VT220" title="VT220">VT220</a> (1983)</li> <li><a href="/wiki/VT240" class="mw-redirect" title="VT240">VT240</a></li> <li><a href="/wiki/VT241" class="mw-redirect" title="VT241">VT241</a></li> <li><a href="/wiki/VT320" title="VT320">VT320</a> (1987)</li> <li><a href="/wiki/VT330" class="mw-redirect" title="VT330">VT330</a></li> <li><a href="/wiki/VT340" class="mw-redirect" title="VT340">VT340</a></li> <li><a href="/wiki/VT420" title="VT420">VT420</a> (1990)</li> <li><a href="/wiki/VT1000" title="VT1000">VT1000</a> (1990)</li> <li><a href="/wiki/VT510" class="mw-redirect" title="VT510">VT510</a> (1993)</li> <li><a href="/wiki/VT520" title="VT520">VT520</a> (1994)</li> <li><a href="/wiki/VT525" class="mw-redirect" title="VT525">VT525</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Operating_system" title="Operating system">Operating<br />systems</a></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/PDP-7#Software" title="PDP-7">DECsys</a></li> <li><a href="/wiki/4K_Disk_Monitor_System" class="mw-redirect" title="4K Disk Monitor System">4K DMS</a></li> <li><a href="/wiki/Commercial_Operating_System" title="Commercial Operating System">COS</a></li> <li><a href="/wiki/TOPS-10" title="TOPS-10">TOPS-10</a></li> <li><a href="/wiki/RSX-15" class="mw-redirect" title="RSX-15">RSX-15</a></li> <li><a href="/wiki/TSS/8" title="TSS/8">TSS/8</a></li> <li><a href="/wiki/OS/8" title="OS/8">OS/8</a></li> <li><a href="/wiki/DEC_BATCH-11/DOS-11" title="DEC BATCH-11/DOS-11">DOS-11</a></li> <li><a href="/wiki/RT-11" title="RT-11">RT-11</a></li> <li><a href="/wiki/RSTS/E" title="RSTS/E">RSTS/E</a></li> <li><a href="/wiki/RSX-11" title="RSX-11">RSX-11</a> <ul><li><a href="/wiki/Interactive_Application_System" title="Interactive Application System">IAS</a></li></ul></li> <li><a href="/wiki/MUMPS#1970s" title="MUMPS">DSM-11</a></li> <li><a href="/wiki/TOPS-20" title="TOPS-20">TOPS-20</a></li> <li><a href="/wiki/OpenVMS" title="OpenVMS">VAX/VMS</a></li> <li><a href="/wiki/VAXELN" title="VAXELN">VAXELN</a></li> <li><a href="/wiki/Ultrix" title="Ultrix">Ultrix</a></li> <li><a href="/wiki/DEC_MICA" title="DEC MICA">MICA</a></li> <li><a href="/wiki/Digital_UNIX" class="mw-redirect" title="Digital UNIX">Digital UNIX</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Programming_language" title="Programming language">Programming<br />languages</a></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/BASIC-8" title="BASIC-8">BASIC-8</a></li> <li><a href="/wiki/DIBOL" title="DIBOL">DIBOL</a></li> <li><a href="/wiki/FOCAL_(programming_language)" title="FOCAL (programming language)">FOCAL</a></li> <li><a href="/wiki/MACRO-10" title="MACRO-10">MACRO-10</a></li> <li><a href="/wiki/MACRO-11" title="MACRO-11">MACRO-11</a></li> <li><a href="/wiki/MUMPS" title="MUMPS">MUMPS</a></li> <li><a href="/wiki/VAX_MACRO" title="VAX MACRO">VAX MACRO</a></li> <li><a href="/wiki/DIGITAL_Command_Language" title="DIGITAL Command Language">DIGITAL Command Language</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Character_encoding" title="Character encoding">Character sets</a></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/Multinational_Character_Set" title="Multinational Character Set">Code page 1100</a> (Multinational)</li> <li><a href="/wiki/Code_page_1287" title="Code page 1287">Code page 1287</a> (Greek)</li> <li><a href="/wiki/Code_page_1288" title="Code page 1288">Code page 1288</a> (Turkish)</li> <li><a href="/wiki/DEC_Hebrew" title="DEC Hebrew">Hebrew</a></li> <li><a href="/wiki/National_Replacement_Character_Set" title="National Replacement Character Set">National Replacement</a></li> <li><a href="/wiki/DEC_RADIX_50" title="DEC RADIX 50">RADIX 50</a></li> <li><a href="/wiki/DEC_Special_Graphics" title="DEC Special Graphics">Special Graphics</a></li> <li><a href="/wiki/DEC_Technical_Character_Set" title="DEC Technical Character Set">Technical</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Bus_(computing)" title="Bus (computing)">Bus standards</a></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/Digital_Storage_Systems_Interconnect" title="Digital Storage Systems Interconnect">Digital Storage Systems Interconnect</a></li> <li><a class="mw-selflink selflink">Massbus</a></li> <li><a href="/wiki/Q-Bus" title="Q-Bus">Q-Bus</a></li> <li><a href="/wiki/Standard_Disk_Interconnect" title="Standard Disk Interconnect">Standard Disk Interconnect</a></li> <li><a href="/wiki/Synchronous_Backplane_Interconnect" title="Synchronous Backplane Interconnect">Synchronous Backplane Interconnect</a></li> <li><a href="/wiki/TURBOchannel" title="TURBOchannel">TURBOchannel</a></li> <li><a href="/wiki/Unibus" title="Unibus">Unibus</a></li> <li><a href="/wiki/VAXBI_bus" title="VAXBI bus">VAXBI bus</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other <a href="/wiki/Computer_hardware" title="Computer hardware">hardware</a></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/DECtalk" title="DECtalk">DECtalk</a></li> <li><a href="/wiki/DECtape" title="DECtape">DECtape</a></li> <li><a href="/wiki/DECwriter" title="DECwriter">DECwriter</a></li> <li><a href="/wiki/Digital_Linear_Tape" title="Digital Linear Tape">Digital Linear Tape</a></li> <li><a href="/wiki/Dynamically_Redefined_Character_Set" title="Dynamically Redefined Character Set">Dynamically Redefined Character Set</a></li> <li><a href="/wiki/Firefly_(cache_coherence_protocol)" title="Firefly (cache coherence protocol)">Firefly</a></li> <li><a href="/wiki/Flip-Chip_module" title="Flip-Chip module">Flip-Chip module</a></li> <li><a href="/wiki/Gold_key_(DEC)" title="Gold key (DEC)">Gold key</a></li> <li><a href="/wiki/LK201" title="LK201">LK201</a></li> <li><a href="/wiki/LK421" title="LK421">LK421</a></li> <li><a href="/wiki/Mass_Storage_Control_Protocol" title="Mass Storage Control Protocol">Mass Storage Control Protocol</a></li> <li><a href="/wiki/PALcode" title="PALcode">PALcode</a></li> <li><a href="/wiki/RA90" title="RA90">RA90</a></li> <li><a href="/wiki/RK05" title="RK05">RK05</a></li> <li><a href="/wiki/RL02" title="RL02">RL02</a></li> <li><a href="/wiki/Star_coupler" title="Star coupler">Star coupler</a></li> <li><a href="/wiki/System_Module" title="System Module">System Module</a></li> <li><a href="/wiki/TU81" title="TU81">TU81</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related topics</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/AdvFS" title="AdvFS">AdvFS</a></li> <li><a href="/wiki/AltaVista" title="AltaVista">AltaVista</a></li> <li><a href="/wiki/Compaq" title="Compaq">Compaq</a></li> <li><i><a href="/wiki/CPU_Wars" title="CPU Wars">CPU Wars</a></i></li> <li><a href="/wiki/DECnet" title="DECnet">DECnet</a></li> <li><a href="/wiki/DECUS" title="DECUS">DECUS</a> <ul><li><a href="/wiki/HP-Interex" title="HP-Interex">HP-Interex</a></li></ul></li> <li><a href="/wiki/Digital_Federal_Credit_Union" title="Digital Federal Credit Union">Digital Federal Credit Union</a></li> <li><a href="/wiki/Dynamic_debugging_technique" title="Dynamic debugging technique">Dynamic debugging technique</a></li> <li><a href="/wiki/FX!32" title="FX!32">FX!32</a></li> <li><a href="/wiki/Local_Area_Transport" title="Local Area Transport">Local Area Transport</a></li> <li><a href="/wiki/Maintenance_Operations_Protocol" title="Maintenance Operations Protocol">Maintenance Operations Protocol</a></li> <li><a href="/wiki/On-line_Debugging_Tool" title="On-line Debugging Tool">On-line Debugging Tool</a></li> <li><a href="/wiki/PALcode" title="PALcode">PALcode</a></li> <li><a href="/wiki/Record_Management_Services" title="Record Management Services">Record Management Services</a></li> <li><a href="/wiki/ReGIS" title="ReGIS">ReGIS</a></li> <li>Sequence and Batch Language</li> <li><a href="/wiki/Sixel" title="Sixel">Sixel</a></li> <li><a href="/wiki/System_Reference_Manual" class="mw-redirect" title="System Reference Manual">System Reference Manual</a></li> <li><a href="/wiki/DEC_Systems_Research_Center" title="DEC Systems Research Center">Systems Research Center</a></li> <li><a href="/wiki/TD/SMP" title="TD/SMP">TD/SMP</a></li> <li><i><a href="/wiki/The_Ultimate_Entrepreneur" title="The Ultimate Entrepreneur">The Ultimate Entrepreneur</a></i></li> <li><a href="/wiki/VT640" title="VT640">VT640</a></li> <li><a href="/wiki/WPS-8" title="WPS-8">WPS-8</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="3"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Template"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/16px-Symbol_template_class_pink.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/23px-Symbol_template_class_pink.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/83/Symbol_template_class_pink.svg/31px-Symbol_template_class_pink.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Template:DEC_hardware" title="Template:DEC hardware">Computers template</a></li> <li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Digital_Equipment_Corporation" title="Category:Digital Equipment Corporation">Category</a></li> <li><span class="noviewer" typeof="mw:File"><span title="Commons page"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span> <a href="https://commons.wikimedia.org/wiki/Category:Digital_Equipment_Corporation" class="extiw" title="commons:Category:Digital Equipment Corporation">Commons</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Technical_and_de_facto_standards_for_wired_computer_buses" style="padding:3px"><table class="nowraplinks 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:Computer_bus" title="Template:Computer bus"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Computer_bus" title="Template talk:Computer bus"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Computer_bus" title="Special:EditPage/Template:Computer bus"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Technical_and_de_facto_standards_for_wired_computer_buses" style="font-size:114%;margin:0 4em"><a href="/wiki/Technical_standard" title="Technical standard">Technical</a> and <a href="/wiki/De_facto_standard" title="De facto standard"><i>de facto</i> standards</a> for <a href="/wiki/Wired_communication" title="Wired communication">wired</a> <a href="/wiki/Bus_(computing)" title="Bus (computing)">computer buses</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">General</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/System_bus" title="System bus">System bus</a></li> <li><a href="/wiki/Front-side_bus" title="Front-side bus">Front-side bus</a></li> <li><a href="/wiki/Back-side_bus" title="Back-side bus">Back-side bus</a></li> <li><a href="/wiki/Daisy_chain_(electrical_engineering)" title="Daisy chain (electrical engineering)">Daisy chain</a></li> <li><a href="/wiki/Control_bus" title="Control bus">Control bus</a></li> <li><a href="/wiki/Address_bus" class="mw-redirect" title="Address bus">Address bus</a></li> <li><a href="/wiki/Bus_contention" title="Bus contention">Bus contention</a></li> <li><a href="/wiki/Bus_mastering" title="Bus mastering">Bus mastering</a></li> <li><a href="/wiki/Network_on_a_chip" title="Network on a chip">Network on a chip</a></li> <li><a href="/wiki/Plug_and_play" title="Plug and play">Plug and play</a></li> <li><a href="/wiki/List_of_interface_bit_rates#Computer_buses" title="List of interface bit rates">List of bus bandwidths</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Standards</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/SS-50_bus" title="SS-50 bus">SS-50 bus</a></li> <li><a href="/wiki/S-100_bus" title="S-100 bus">S-100 bus</a></li> <li><a href="/wiki/Multibus" title="Multibus">Multibus</a></li> <li><a href="/wiki/Unibus" title="Unibus">Unibus</a></li> <li><a href="/wiki/VAXBI_bus" title="VAXBI bus">VAXBI</a></li> <li><a href="/wiki/MBus_(SPARC)" title="MBus (SPARC)">MBus</a></li> <li><a href="/wiki/STD_Bus" title="STD Bus">STD Bus</a></li> <li><a href="/wiki/System_Management_Bus" title="System Management Bus">SMBus</a></li> <li><a href="/wiki/Q-Bus" title="Q-Bus">Q-Bus</a></li> <li><a href="/wiki/Europe_Card_Bus" title="Europe Card Bus">Europe Card Bus</a></li> <li><a href="/wiki/Industry_Standard_Architecture" title="Industry Standard Architecture">ISA</a></li> <li><a href="/wiki/STEbus" title="STEbus">STEbus</a></li> <li><a href="/wiki/Amiga_Zorro_II" title="Amiga Zorro II">Zorro II</a></li> <li><a href="/wiki/Amiga_Zorro_III" title="Amiga Zorro III">Zorro III</a></li> <li><a href="/wiki/Computer_Automated_Measurement_and_Control" title="Computer Automated Measurement and Control">CAMAC</a></li> <li><a href="/wiki/FASTBUS" title="FASTBUS">FASTBUS</a></li> <li><a href="/wiki/Low_Pin_Count" title="Low Pin Count">LPC</a></li> <li><a href="/wiki/HP_Precision_Bus" title="HP Precision Bus">HP Precision Bus</a></li> <li><a href="/wiki/Extended_Industry_Standard_Architecture" title="Extended Industry Standard Architecture">EISA</a></li> <li><a href="/wiki/VMEbus" title="VMEbus">VME</a></li> <li><a href="/wiki/VME_eXtensions_for_Instrumentation" title="VME eXtensions for Instrumentation">VXI</a></li> <li><a href="/wiki/VXS" title="VXS">VXS</a></li> <li><a href="/wiki/VPX" title="VPX">VPX</a></li> <li><a href="/wiki/NuBus" title="NuBus">NuBus</a></li> <li><a href="/wiki/TURBOchannel" title="TURBOchannel">TURBOchannel</a></li> <li><a href="/wiki/Micro_Channel_architecture" title="Micro Channel architecture">MCA</a></li> <li><a href="/wiki/SBus" title="SBus">SBus</a></li> <li><a href="/wiki/VESA_Local_Bus" title="VESA Local Bus">VLB</a></li> <li><a href="/wiki/GSC_bus" title="GSC bus">HP GSC bus</a></li> <li><a href="/wiki/InfiniBand" title="InfiniBand">InfiniBand</a></li> <li><a href="/wiki/Ethernet" title="Ethernet">Ethernet</a></li> <li><a href="/wiki/Ultra_Port_Architecture" title="Ultra Port Architecture">UPA</a></li> <li><a href="/wiki/Peripheral_Component_Interconnect" title="Peripheral Component Interconnect">PCI</a></li> <li><a href="/wiki/PCI-X" title="PCI-X">PCI Extended (PCI-X)</a></li> <li><a href="/wiki/PCI_eXtensions_for_Instrumentation" title="PCI eXtensions for Instrumentation">PXI</a></li> <li><a href="/wiki/PCI_Express" title="PCI Express">PCI Express (PCIe)</a></li> <li><a href="/wiki/Accelerated_Graphics_Port" title="Accelerated Graphics Port">AGP</a></li> <li><a href="/wiki/Compute_Express_Link" title="Compute Express Link">Compute Express Link (CXL)</a></li> <li><a href="/wiki/Direct_Media_Interface" title="Direct Media Interface">Direct Media Interface (DMI)</a></li> <li><a href="/wiki/RapidIO" title="RapidIO">RapidIO</a></li> <li><a href="/wiki/Intel_QuickPath_Interconnect" title="Intel QuickPath Interconnect">Intel QuickPath Interconnect</a></li> <li><a href="/wiki/NVLink" title="NVLink">NVLink</a></li> <li><a href="/wiki/HyperTransport" title="HyperTransport">HyperTransport</a> <ul><li><a href="/wiki/Infinity_Fabric" class="mw-redirect" title="Infinity Fabric">Infinity Fabric</a></li></ul></li> <li><a href="/wiki/Intel_Ultra_Path_Interconnect" title="Intel Ultra Path Interconnect">Intel Ultra Path Interconnect</a></li> <li><a href="/wiki/Coherent_Accelerator_Processor_Interface" title="Coherent Accelerator Processor Interface">Coherent Accelerator Processor Interface (CAPI)</a></li> <li><a href="/wiki/SpaceWire" title="SpaceWire">SpaceWire</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Storage</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ST-506/ST-412" title="ST-506/ST-412">ST-506</a></li> <li><a href="/wiki/Enhanced_Small_Disk_Interface" title="Enhanced Small Disk Interface">ESDI</a></li> <li><a href="/wiki/Intelligent_Peripheral_Interface" title="Intelligent Peripheral Interface">IPI</a></li> <li><a href="/wiki/Storage_Module_Device" title="Storage Module Device">SMD</a></li> <li><a href="/wiki/Parallel_ATA" title="Parallel ATA">Parallel ATA (PATA)</a></li> <li><a href="/wiki/Bus_and_Tag" title="Bus and Tag">Bus and Tag</a></li> <li><a href="/wiki/Digital_Storage_Systems_Interconnect" title="Digital Storage Systems Interconnect">DSSI</a></li> <li><a href="/wiki/HIPPI" title="HIPPI">HIPPI</a></li> <li><a href="/wiki/SATA" title="SATA">Serial ATA (SATA)</a></li> <li><a href="/wiki/SCSI" title="SCSI">SCSI</a> <ul><li><a href="/wiki/Parallel_SCSI" title="Parallel SCSI">Parallel</a></li> <li><a href="/wiki/Serial_Attached_SCSI" title="Serial Attached SCSI">SAS</a></li></ul></li> <li><a href="/wiki/ESCON" title="ESCON">ESCON</a></li> <li><a href="/wiki/Fibre_Channel" title="Fibre Channel">Fibre Channel</a></li> <li><a href="/wiki/Serial_Storage_Architecture" title="Serial Storage Architecture">SSA</a></li> <li><a href="/wiki/SATA_Express" title="SATA Express">SATAe</a></li> <li>PCI Express (via <a href="/wiki/Advanced_Host_Controller_Interface" title="Advanced Host Controller Interface">AHCI</a> or <a href="/wiki/NVM_Express" title="NVM Express">NVMe</a> logical device interface)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Peripheral</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Apple_Desktop_Bus" title="Apple Desktop Bus">Apple Desktop Bus</a></li> <li><a href="/wiki/Atari_SIO" title="Atari SIO">Atari SIO</a></li> <li><a href="/wiki/Digital_Control_Bus" title="Digital Control Bus">DCB</a></li> <li><a href="/wiki/Commodore_bus" title="Commodore bus">Commodore bus</a></li> <li><a href="/wiki/HP-IL" title="HP-IL">HP-IL</a></li> <li><a href="/wiki/HIL_bus" title="HIL bus">HIL</a></li> <li><a href="/wiki/MIDI" title="MIDI">MIDI</a></li> <li><a href="/wiki/RS-232" title="RS-232">RS-232</a></li> <li><a href="/wiki/RS-422" title="RS-422">RS-422</a></li> <li><a href="/wiki/RS-423" title="RS-423">RS-423</a></li> <li><a href="/wiki/RS-485" title="RS-485">RS-485</a></li> <li><a href="/wiki/Lightning_(connector)" title="Lightning (connector)">Lightning</a></li> <li><a href="/wiki/DMX512#DMX512-A" title="DMX512">DMX512-A</a></li> <li><a href="/wiki/IEEE-488" class="mw-redirect" title="IEEE-488">IEEE-488 (GPIB)</a></li> <li><a href="/wiki/IEEE_1284" title="IEEE 1284">IEEE-1284 (parallel port)</a></li> <li><a href="/wiki/IEEE_1394" title="IEEE 1394">IEEE-1394 (FireWire)</a></li> <li><a href="/wiki/UNI/O" title="UNI/O">UNI/O</a></li> <li><a href="/wiki/1-Wire" title="1-Wire">1-Wire</a></li> <li><a href="/wiki/I%C2%B2C" title="I²C">I²C</a> (<a href="/wiki/ACCESS.bus" title="ACCESS.bus">ACCESS.bus</a>, <a href="/wiki/Power_Management_Bus" title="Power Management Bus">PMBus</a>, <a href="/wiki/System_Management_Bus" title="System Management Bus">SMBus</a>)</li> <li><a href="/wiki/I3C_(bus)" title="I3C (bus)">I3C</a></li> <li><a href="/wiki/Serial_Peripheral_Interface" title="Serial Peripheral Interface">SPI</a></li> <li><a href="/wiki/IEC_61030" title="IEC 61030">D²B</a></li> <li><a href="/wiki/Parallel_SCSI" title="Parallel SCSI">Parallel SCSI</a></li> <li><a href="/wiki/Profibus" title="Profibus">Profibus</a></li> <li><a href="/wiki/USB" title="USB">USB</a></li> <li><a href="/wiki/Camera_Link" title="Camera Link">Camera Link</a></li> <li><a href="/wiki/PCI_Express#PCI_Express_External_Cabling" title="PCI Express">External PCIe</a></li> <li><a href="/wiki/Thunderbolt_(interface)" title="Thunderbolt (interface)">Thunderbolt</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Audio</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ADAT_Lightpipe" title="ADAT Lightpipe">ADAT Lightpipe</a></li> <li><a href="/wiki/AES3" title="AES3">AES3</a></li> <li><a href="/wiki/Intel_High_Definition_Audio" title="Intel High Definition Audio">Intel HD Audio</a></li> <li><a href="/wiki/I%C2%B2S" title="I²S">I²S</a></li> <li><a href="/wiki/MADI" title="MADI">MADI</a></li> <li><a href="/wiki/McASP" title="McASP">McASP</a></li> <li><a href="/wiki/S/PDIF" title="S/PDIF">S/PDIF</a></li> <li><a href="/wiki/TOSLINK" title="TOSLINK">TOSLINK</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Portable</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/PC_Card" title="PC Card">PC Card</a></li> <li><a href="/wiki/ExpressCard" title="ExpressCard">ExpressCard</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Embedded</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Multidrop_bus" title="Multidrop bus">Multidrop bus</a></li> <li><a href="/wiki/CoreConnect" title="CoreConnect">CoreConnect</a></li> <li><a href="/wiki/Advanced_Microcontroller_Bus_Architecture" title="Advanced Microcontroller Bus Architecture">AMBA</a> (<a href="/wiki/Advanced_eXtensible_Interface" title="Advanced eXtensible Interface">AXI</a>)</li> <li><a href="/wiki/Wishbone_(computer_bus)" title="Wishbone (computer bus)">Wishbone</a></li> <li><a href="/wiki/SLIMbus" title="SLIMbus">SLIMbus</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><small>Interfaces are listed by their speed in the (roughly) ascending order, so the interface at the end of each section should be the fastest.</small><br /><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" 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