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class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" 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data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Main_features_of_the_Q-bus" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Main_features_of_the_Q-bus"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Main features of the Q-bus</span> </div> </a> <ul id="toc-Main_features_of_the_Q-bus-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Physical_characteristics" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Physical_characteristics"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Physical characteristics</span> </div> </a> <ul id="toc-Physical_characteristics-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Logic_minimization" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Logic_minimization"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Logic minimization</span> </div> </a> <ul id="toc-Logic_minimization-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Compatibility" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Compatibility"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Compatibility</span> </div> </a> <ul id="toc-Compatibility-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Soviet_clones" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Soviet_clones"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Soviet clones</span> </div> </a> <ul id="toc-Soviet_clones-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Cycle_Types" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Cycle_Types"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Cycle Types</span> </div> </a> <ul id="toc-Cycle_Types-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Device_Types" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Device_Types"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Device Types</span> </div> </a> <ul id="toc-Device_Types-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Interfaces" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Interfaces"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Interfaces</span> </div> </a> <ul id="toc-Interfaces-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>External links</span> </div> </a> <ul id="toc-External_links-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">10</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div 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<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">Computer bus</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">Q-Bus</caption><tbody><tr><td colspan="2" class="infobox-subheader">Q-Bus</td></tr><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:DEC_MicroVAX_II_CPU_KA630-AA_M7606.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3b/DEC_MicroVAX_II_CPU_KA630-AA_M7606.jpg/220px-DEC_MicroVAX_II_CPU_KA630-AA_M7606.jpg" decoding="async" width="220" height="185" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3b/DEC_MicroVAX_II_CPU_KA630-AA_M7606.jpg/330px-DEC_MicroVAX_II_CPU_KA630-AA_M7606.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3b/DEC_MicroVAX_II_CPU_KA630-AA_M7606.jpg/440px-DEC_MicroVAX_II_CPU_KA630-AA_M7606.jpg 2x" data-file-width="7149" data-file-height="6009" /></a></span><div class="infobox-caption">DEC <a href="/wiki/MicroVAX" title="MicroVAX">MicroVAX</a> II CPU card (quad height)</div></td></tr><tr><th scope="row" class="infobox-label">Created by</th><td class="infobox-data"><a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a></td></tr><tr><th scope="row" class="infobox-label">Supersedes</th><td class="infobox-data"><a href="/wiki/Unibus" title="Unibus">Unibus</a></td></tr><tr><th scope="row" class="infobox-label">Superseded by</th><td class="infobox-data"><a href="/wiki/VAXBI_bus" title="VAXBI bus">VAXBI bus</a> (1986)</td></tr><tr><th scope="row" class="infobox-label">Width in bits</th><td class="infobox-data">8 or 16-bit data, 16-bit address extended to 22-bit</td></tr><tr><th scope="row" class="infobox-label"><abbr title="Number">No.</abbr> of devices</th><td class="infobox-data">127 in theory, ~20 in practice</td></tr><tr><th scope="row" class="infobox-label">Style</th><td class="infobox-data"><a href="/wiki/Parallel_communication" title="Parallel communication">Parallel</a></td></tr><tr><th scope="row" class="infobox-label">Hotplugging interface</th><td class="infobox-data">No</td></tr><tr><th scope="row" class="infobox-label">External interface</th><td class="infobox-data">No</td></tr></tbody></table> <p>The <b>Q-bus</b>,<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> also known as the <b>LSI-11 Bus</b>, is one of several <a href="/wiki/Bus_(computing)" title="Bus (computing)">bus</a> technologies used with <a href="/wiki/Programmed_Data_Processor" title="Programmed Data Processor">PDP</a> and <a href="/wiki/VAX" title="VAX">MicroVAX</a> computer systems previously manufactured by the <a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> of <a href="/wiki/Maynard,_Massachusetts" title="Maynard, Massachusetts">Maynard</a>, <a href="/wiki/Massachusetts" title="Massachusetts">Massachusetts</a>. </p><p>The Q-bus is a less expensive version of <a href="/wiki/Unibus" title="Unibus">Unibus</a> using multiplexing so that address and data signals share the same wires.<sup id="cite_ref-:0_2-0" class="reference"><a href="#cite_note-:0-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> This allows both a physically smaller and less-expensive implementation of essentially the same functionality. </p><p>Over time, the physical address range of the Q-bus was expanded from 16 to 18 and then 22 bits. Block transfer modes were also added to the Q-bus.<sup id="cite_ref-:0_2-1" class="reference"><a href="#cite_note-:0-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Main_features_of_the_Q-bus">Main features of the Q-bus</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=1" title="Edit section: Main features of the Q-bus"><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:DEC_LSI11-23.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ef/DEC_LSI11-23.jpg/220px-DEC_LSI11-23.jpg" decoding="async" width="220" height="201" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ef/DEC_LSI11-23.jpg/330px-DEC_LSI11-23.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ef/DEC_LSI11-23.jpg/440px-DEC_LSI11-23.jpg 2x" data-file-width="555" data-file-height="507" /></a><figcaption>LSI-11/23 Q-Bus <a href="/wiki/Expansion_card" title="Expansion card">expansion cards</a> and slots</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:BA213.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/BA213.jpg/220px-BA213.jpg" decoding="async" width="220" height="258" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/BA213.jpg/330px-BA213.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fe/BA213.jpg/440px-BA213.jpg 2x" data-file-width="682" data-file-height="800" /></a><figcaption>DEC BA213 cabinet; 12 Q-Bus-22 slots</figcaption></figure><p>The Q-bus is arranged as a series of <a href="/wiki/Expansion_card" title="Expansion card">modules</a> installed in one or more <a href="/wiki/Backplane" title="Backplane">backplanes</a>. </p><p>Like the Unibus before it, the Q-bus uses:<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> </p> <ul><li><i><a href="/wiki/Memory-mapped_I/O" class="mw-redirect" title="Memory-mapped I/O">Memory-mapped I/O</a></i></li> <li><i><a href="/wiki/Byte_addressing" title="Byte addressing">Byte addressing</a></i></li> <li>A strict <i><a href="/wiki/Master-slave_(computers)" class="mw-redirect" title="Master-slave (computers)">master-slave</a></i> relationship between devices on the bus</li> <li><i><a href="/wiki/Asynchronous_communication" title="Asynchronous communication">Asynchronous signaling</a></i></li></ul> <p><i>Memory-mapped I/O</i> means that data cycles between any two devices, whether CPU, memory, or I/O devices, use the same protocols. On the Unibus, a range of physical addresses are dedicated for I/O devices. The Q-bus simplifies this design by providing a specific signal (originally called <i>BBS7</i>, <i>Bus Bank Select 7</i> but later generalized to be called <i>BBSIO</i>, <i>Bus Bank Select I/O</i>) that selects the range of addresses used by the I/O devices. </p><p><i>Byte addressing</i> means that the physical address passed on the Unibus is interpreted as the address of a byte-sized quantity of data. Because the bus actually contains a data path that is two bytes wide, address bit [0] is subject to special interpretation and data on the bus has to travel in the correct <a href="/w/index.php?title=Byte_lane&action=edit&redlink=1" class="new" title="Byte lane (page does not exist)">byte lanes</a>. </p><p>A strict <i>Master-Slave</i> relationship means that at any point in time, only one device can be the <i>Master</i> of the Q-bus. This <i>master device</i> can initiate data transactions which can then be responded to by a maximum of one selected <i>slave device</i>. (This had no effect on whether a given bus cycle is reading or writing data; the bus master can command either type of transaction.) At the end of the bus cycle, a <i><a href="/wiki/Bus_arbitration" class="mw-redirect" title="Bus arbitration">bus arbitration</a></i> protocol then selects the next device to be given mastery of the bus. </p><p><i>Asynchronous signaling</i> means that the bus has no fixed cycle time; the duration of any particular data transfer cycle on the bus is determined solely by the master and slave devices participating in the current data cycle. These devices use <i><a href="/wiki/Handshake_(computing)" title="Handshake (computing)">handshake</a></i> signals to control the timing of the data cycle. <a href="/wiki/Timeout_(computing)" title="Timeout (computing)">Timeout logic</a> within the master device limits the maximum allowed length of any given bus cycle. </p><p>Depending on its generation, the Q-bus contains 16, 18, or 22 <i>BDAL</i> (<i>Bus Data/Address Line</i>) lines. 16, 18, or 22 BDAL lines are used for the physical address portion of each bus cycle. Eight or 16 DBAL lines are then re-used for the data portion(s) of each bus cycle. Newer generations of the bus allow <a href="/wiki/Burst_mode_(computing)" title="Burst mode (computing)"><i>block mode</i> transfer</a> where a single bus address can be followed by more than one data cycle (with the transfers taking place at consecutive bus addresses). Because the address portion of each bus cycle can not transfer data, the use of block mode means fewer address cycles and more time for data cycles, allowing increased bus data transfer <a href="/wiki/Bandwidth_(computing)" title="Bandwidth (computing)">bandwidth</a>. </p><p><a href="/wiki/Bus_master" class="mw-redirect" title="Bus master">Bus mastery</a> is awarded based on an I/O card's topological proximity to the <a href="/wiki/Bus_arbiter" class="mw-redirect" title="Bus arbiter">bus arbitrator</a> (at the logical front of the bus); closer cards are granted priority over further cards. </p><p>Interrupts can be delivered to the <i>Interrupt Fielding Processor</i> at any of four <a href="/wiki/Interrupt_priority_level" title="Interrupt priority level">interrupt priority levels</a>. Within a given level, the cards closer to the IFP (at the front of the bus) take priority over cards further back on the bus. <a href="/wiki/Vectored_Interrupt" class="mw-redirect" title="Vectored Interrupt">Interrupts are vectored</a>: a card requesting an interrupt has its interrupt vector read by the IFP. In this way, the interrupts from all I/O cards in the system can be distinguished with no ambiguity. </p> <div class="mw-heading mw-heading2"><h2 id="Physical_characteristics">Physical characteristics</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=2" title="Edit section: Physical characteristics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Q-bus modules are configured as printed-circuit boards with gold-plated card-edge connectors which mate with corresponding slots on a backplane. The edge connectors on the modules are split into individual "fingers," similarly to Unibus modules, but are limited to four connectors, compared to the six of Unibus. Modules are available in either double-height (two connectors) or quad-height (four connectors) sizes. This nomenclature is somewhat non-intuitive, as the difference between the two is actually the <i>width</i> of the PCB. Quad-height modules tend to be used for CPUs, memory, video processors, and other high-bandwidth components, whereas double-height modules tend to be used for interface cards, connector breakout boards, real-time clocks, ROM/microcode, and other relatively low-bandwidth components. Some exceptions are the double-height LSI-11/2, KDF11-A, and KDJ11-A CPUs, and many early small-capacity memory modules. </p> <div class="mw-heading mw-heading2"><h2 id="Logic_minimization">Logic minimization</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=3" title="Edit section: Logic minimization"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>As with the Unibus, the signaling was carefully optimized so that the minimum amount of logic is required across the entire bus system. Asynchronous signaling is used but de-skewing of addresses and data is the responsibility of the current bus master, minimizing the complexity of the bus slave devices. The responsibility for timing-out failed bus cycles also is placed in the master devices. Similarly, the complexities of handling interrupt transactions are concentrated into the single <i>Interrupt-Fielding Processor</i> (the PDP-11 or VAX-11 computer) in the system. </p> <div class="mw-heading mw-heading2"><h2 id="Compatibility">Compatibility</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=4" title="Edit section: Compatibility"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The design of the Q-bus was very closely related to the design of the Unibus both in spirit and in detailed implementation. Adapters were available from Digital and from third parties that allow Q-bus devices to be connected to Unibus-based computers and vice versa.<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> A number of I/O devices were available in either Unibus or Q-bus flavors; some of these devices have minor differences while many others were essentially identical. </p> <div class="mw-heading mw-heading2"><h2 id="Soviet_clones">Soviet clones</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=5" title="Edit section: Soviet clones"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In Soviet systems (see <a href="/wiki/1801_series_CPU" title="1801 series CPU">1801 series CPU</a>), the Q-Bus architecture is called <b>МПИ</b> (<i>Магистральный Параллельный Интерфейс</i>, or parallel bus interface). Its main difference is that it supports up to four processors on the same bus. Otherwise it is completely binary and electrically compatible with the standard Q-Bus, except for the physical layout of connectors. </p> <div class="mw-heading mw-heading2"><h2 id="Cycle_Types">Cycle Types</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=6" title="Edit section: Cycle Types"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Q-Bus supports 6 basic transaction types:<sup id="cite_ref-:0_2-2" class="reference"><a href="#cite_note-:0-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <pre>DATI Data in - master read - note no DATIB (not required) DATO Data out - master write DATOB Data out (byte) DATIO Data in/out DATIOB Data in/out (byte) IAK Interrupt Acknowledge </pre> <div class="mw-heading mw-heading2"><h2 id="Device_Types">Device Types</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=7" title="Edit section: Device Types"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A wide range of module types are available for the Q-Bus. Generally, they can be categorized as: </p> <ul><li>CPU modules</li> <li>Memory modules</li> <li>Interface modules</li> <li>System modules (grant continuity cards, connector breakout boards, etc)</li></ul> <div class="mw-heading mw-heading2"><h2 id="Interfaces">Interfaces</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Q-Bus&action=edit&section=8" title="Edit section: Interfaces"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1237032888/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner img{background-color:white}}</style><div class="thumb tmulti tright"><div class="thumbinner multiimageinner" style="width:442px;max-width:442px"><div class="trow"><div class="tsingle" style="width:245px;max-width:245px"><div class="thumbimage" style="height:147px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:Bubbl-tec_QSB-11A_Bubbl-Board_for_DEC_Qbus,_component_side_(19257373711).jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Bubbl-tec_QSB-11A_Bubbl-Board_for_DEC_Qbus%2C_component_side_%2819257373711%29.jpg/243px-Bubbl-tec_QSB-11A_Bubbl-Board_for_DEC_Qbus%2C_component_side_%2819257373711%29.jpg" decoding="async" width="243" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Bubbl-tec_QSB-11A_Bubbl-Board_for_DEC_Qbus%2C_component_side_%2819257373711%29.jpg/365px-Bubbl-tec_QSB-11A_Bubbl-Board_for_DEC_Qbus%2C_component_side_%2819257373711%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Bubbl-tec_QSB-11A_Bubbl-Board_for_DEC_Qbus%2C_component_side_%2819257373711%29.jpg/486px-Bubbl-tec_QSB-11A_Bubbl-Board_for_DEC_Qbus%2C_component_side_%2819257373711%29.jpg 2x" data-file-width="4424" data-file-height="2684" /></a></span></div><div class="thumbcaption">1 MBit <a href="/wiki/Bubble_memory" title="Bubble memory">Bubble memory</a> dual-width Q-Bus <a href="/wiki/Expansion_card" title="Expansion card">expansion card</a></div></div><div class="tsingle" style="width:193px;max-width:193px"><div class="thumbimage" style="height:147px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:Core_memory.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4f/Core_memory.jpg/191px-Core_memory.jpg" decoding="async" width="191" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4f/Core_memory.jpg/287px-Core_memory.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4f/Core_memory.jpg/382px-Core_memory.jpg 2x" data-file-width="624" data-file-height="480" /></a></span></div><div class="thumbcaption">8K × 19 bit <a href="/wiki/Core_memory" class="mw-redirect" title="Core memory">core memory</a> quad-width Q-Bus <a href="/wiki/Expansion_card" title="Expansion card">expansion card</a></div></div></div><div class="trow"><div class="tsingle" style="width:440px;max-width:440px"><div class="thumbimage" style="height:350px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:Intergraph_PCB484_MicroVAX_II_memory_module.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Intergraph_PCB484_MicroVAX_II_memory_module.jpg/438px-Intergraph_PCB484_MicroVAX_II_memory_module.jpg" decoding="async" width="438" height="351" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Intergraph_PCB484_MicroVAX_II_memory_module.jpg/657px-Intergraph_PCB484_MicroVAX_II_memory_module.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Intergraph_PCB484_MicroVAX_II_memory_module.jpg/876px-Intergraph_PCB484_MicroVAX_II_memory_module.jpg 2x" data-file-width="7154" data-file-height="5731" /></a></span></div><div class="thumbcaption">DEC MicroVAX II memory card (quad widhth)</div></div></div></div></div> <p>A wide range of interface cards are available for the Q-Bus. Various Q-bus modules can be dual-width (two sets of fingers, half the total width of the mounting), or quad-width (four sets of fingers, the full width of the mounting), indicating that the module occupies one-half of or all of the Q-bus mounting slot, respectively. </p><p><br /> </p> <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=Q-Bus&action=edit&section=9" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><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="https://web.archive.org/web/20210311023428/http://hoffmanlabs.org/openvms/hwvax/hwqbus.shtml">"HP OpenVMS :: Q-Bus Hardware"</a>. <i>HoffmanLabs</i>. Archived from <a rel="nofollow" class="external text" href="http://hoffmanlabs.org/openvms/hwvax/hwqbus.shtml#topofpage">the original</a> on 11 March 2021.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=HoffmanLabs&rft.atitle=HP+OpenVMS+%3A%3A+Q-Bus+Hardware&rft_id=http%3A%2F%2Fhoffmanlabs.org%2Fopenvms%2Fhwvax%2Fhwqbus.shtml%23topofpage&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQ-Bus" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1 cs1-prop-foreign-lang-source"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20170214163740/http://www.runningserver.com/?page=runningserver.content.thelab.qbussample">"The Lab - Q-Bus Beispielplatine, Selbstgebaute Q-BUS Platinen"</a>. <i>RunningServer.com</i> (in German). Archived from <a rel="nofollow" class="external text" href="http://www.runningserver.com/?page=runningserver.content.thelab.qbussample">the original</a> on 14 February 2017.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=RunningServer.com&rft.atitle=The+Lab+-+Q-Bus+Beispielplatine%2C+Selbstgebaute+Q-BUS+Platinen&rft_id=http%3A%2F%2Fwww.runningserver.com%2F%3Fpage%3Drunningserver.content.thelab.qbussample&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQ-Bus" class="Z3988"></span></li> <li><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/dec/standards/EL-00160-00-0_A_DEC_STD_160_LSI-11_Bus_Specification_Sep91.pdf">DEC STD 160: LSI-11 Bus Specification</a></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=Q-Bus&action=edit&section=10" 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"><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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSchmidt1990" class="citation book cs1">Schmidt, Atlant G. (1990). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/digitalbushandbo0000unse/page/n131/mode/2up">"Unibus, Q-Bus and VAXBI Bus"</a></span>. In Di Giacomo Joseph (ed.). <i>Digital bus handbook</i>. McGraw Hill. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0070169233" title="Special:BookSources/0070169233"><bdi>0070169233</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Unibus%2C+Q-Bus+and+VAXBI+Bus&rft.btitle=Digital+bus+handbook&rft.pub=McGraw+Hill&rft.date=1990&rft.isbn=0070169233&rft.aulast=Schmidt&rft.aufirst=Atlant+G.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fdigitalbushandbo0000unse%2Fpage%2Fn131%2Fmode%2F2up&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQ-Bus" class="Z3988"></span></span> </li> <li id="cite_note-:0-2"><span class="mw-cite-backlink">^ <a href="#cite_ref-:0_2-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:0_2-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-:0_2-2"><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 book cs1"><a rel="nofollow" class="external text" href="https://archive.org/details/bitsavers_dechandboomsHandbook1985_21400965"><i>digital Microsystems Handbook 1985</i></a>. 1985.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=digital+Microsystems+Handbook+1985&rft.date=1985&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fbitsavers_dechandboomsHandbook1985_21400965&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQ-Bus" 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 book cs1"><a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/dec/qbus/Digital_Microcomputer_Products_Handbook_1985.pdf"><i>digital Microcomputer Products Handbook</i></a> <span class="cs1-format">(PDF)</span>. 1985.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=digital+Microcomputer+Products+Handbook&rft.date=1985&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fdec%2Fqbus%2FDigital_Microcomputer_Products_Handbook_1985.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQ-Bus" 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 book cs1"><a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/dec/pdp11/handbooks/PDP-11_Bus_Handbook_1979.pdf"><i>PDP-11 Bus Handbook</i></a> <span class="cs1-format">(PDF)</span>. 1979.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=PDP-11+Bus+Handbook&rft.date=1979&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fdec%2Fpdp11%2Fhandbooks%2FPDP-11_Bus_Handbook_1979.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQ-Bus" 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 book cs1"><a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/dec/pdp11/1184/EK-1184E-TM-001_Dec87.pdf"><i>PDP-11/84 System Technical and Reference Manual</i></a> <span class="cs1-format">(PDF)</span>. December 1987. pp. 1‐2, 2‐52–2‐69.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=PDP-11%2F84+System+Technical+and+Reference+Manual&rft.pages=1%E2%80%902%2C+2%E2%80%9052-2%E2%80%9069&rft.date=1987-12&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2Fdec%2Fpdp11%2F1184%2FEK-1184E-TM-001_Dec87.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQ-Bus" 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 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.mw-parser-output .navbox{display:none!important}}</style></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"><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: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 class="mw-selflink selflink">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" 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:Computer_buses" title="Category:Computer buses">Category</a></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="Digital_Equipment_Corporation" 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="3"><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: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 href="/wiki/Massbus" title="Massbus">Massbus</a></li> <li><a class="mw-selflink selflink">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" 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