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class="vector-toc-numb">2</span> <span>3B high-availability processors</span> </div> </a> <ul id="toc-3B_high-availability_processors-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Minicomputers" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Minicomputers"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Minicomputers</span> </div> </a> <button aria-controls="toc-Minicomputers-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 Minicomputers subsection</span> </button> <ul id="toc-Minicomputers-sublist" class="vector-toc-list"> <li id="toc-3B20S" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#3B20S"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>3B20S</span> </div> </a> <ul id="toc-3B20S-sublist" 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</a> <ul id="toc-3B1_desktop_workstation-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>See also</span> </div> </a> <ul id="toc-See_also-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">6</span> <span>References</span> </div> </a> <ul id="toc-References-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">7</span> <span>External links</span> </div> 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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">AT&T/Bell family of computers</div> <p class="mw-empty-elt"> </p> <figure typeof="mw:File/Thumb"><a href="/wiki/File:3B15_computer_in_a_data_center_in_Somerset,_New_Jersey_(ca._1997).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f7/3B15_computer_in_a_data_center_in_Somerset%2C_New_Jersey_%28ca._1997%29.jpg/320px-3B15_computer_in_a_data_center_in_Somerset%2C_New_Jersey_%28ca._1997%29.jpg" decoding="async" width="320" height="240" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f7/3B15_computer_in_a_data_center_in_Somerset%2C_New_Jersey_%28ca._1997%29.jpg/480px-3B15_computer_in_a_data_center_in_Somerset%2C_New_Jersey_%28ca._1997%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/f/f7/3B15_computer_in_a_data_center_in_Somerset%2C_New_Jersey_%28ca._1997%29.jpg 2x" data-file-width="640" data-file-height="480" /></a><figcaption>A 3B15 computer, circa 1997</figcaption></figure> <p>The <b>3B series computers</b><sup id="cite_ref-3Bseries.NYT840328_1-0" class="reference"><a href="#cite_note-3Bseries.NYT840328-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-3Bseries.RoyNYT890316_2-0" class="reference"><a href="#cite_note-3Bseries.RoyNYT890316-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> are a line of minicomputers<sup id="cite_ref-3B2.600NYT870325_3-0" class="reference"><a href="#cite_note-3B2.600NYT870325-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> made between the late 1970s and 1993 by <a href="/wiki/AT%26T_Computer_Systems" title="AT&T Computer Systems">AT&T Computer Systems</a>' <a href="/wiki/Western_Electric" title="Western Electric">Western Electric</a> subsidiary, for use with the company's <a href="/wiki/UNIX" class="mw-redirect" title="UNIX">UNIX</a> operating system. The line primarily consists of the models 3B20, 3B5, 3B15, 3B2, and 3B4000. The series is notable for controlling a series of <a href="/wiki/Electronic_switching_system" title="Electronic switching system">electronic switching systems</a> for <a href="/wiki/Telecommunication" class="mw-redirect" title="Telecommunication">telecommunication</a>, for general computing purposes, and for serving as the historical software porting base for commercial UNIX. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first 3B20D was installed in <a href="/wiki/Fresno,_California" title="Fresno, California">Fresno, California</a> at Pacific Bell.<sup class="noprint Inline-Template" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Manual_of_Style/Dates_and_numbers#Chronological_items" title="Wikipedia:Manual of Style/Dates and numbers"><span title="The time period mentioned near this tag is ambiguous. (August 2021)">when?</span></a></i>]</sup> Within two years, several hundred were in place throughout the <a href="/wiki/Bell_System" title="Bell System">Bell System</a>. Some of the units came with "small, slow hard disks".<sup id="cite_ref-3B2.HC84_4-0" class="reference"><a href="#cite_note-3B2.HC84-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>The general purpose family of 3B computer systems includes the 3B2, 3B5, 3B15, 3B20S, and 3B4000. They run the AT&T <a href="/wiki/UNIX" class="mw-redirect" title="UNIX">UNIX</a> operating system and were named after the successful 3B20D High Availability processor. </p><p>In 1984, after regulatory constraints were lifted, AT&T introduced the 3B20D, 3B20S, 3B5, and 3B2 to the general computer market,<sup id="cite_ref-3Bseries.NYT840328_1-1" class="reference"><a href="#cite_note-3Bseries.NYT840328-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-:0_5-0" class="reference"><a href="#cite_note-:0-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> a move that some commentators saw as an attempt to compete with <a href="/wiki/IBM" title="IBM">IBM</a>.<sup id="cite_ref-unixreview198802_olivetti_6-0" class="reference"><a href="#cite_note-unixreview198802_olivetti-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> In Europe, the 3B computers were distributed by Italian firm <a href="/wiki/Olivetti_computers" title="Olivetti computers">Olivetti</a>, in which AT&T had a minority shareholding.<sup id="cite_ref-:0_5-1" class="reference"><a href="#cite_note-:0-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-unixreview198802_olivetti_6-1" class="reference"><a href="#cite_note-unixreview198802_olivetti-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> After AT&T bought NCR Corporation, effective January 1992, the computers were marketed through NCR sales channels.<sup id="cite_ref-lastunits_7-0" class="reference"><a href="#cite_note-lastunits-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p><p>Having produced 70,000 units, the AT&T Oklahoma City plant stopped manufacturing 3B machines at the end of 1993, with the 3B20D to be the last units manufactured.<sup id="cite_ref-lastunits_7-1" class="reference"><a href="#cite_note-lastunits-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="3B_high-availability_processors">3B high-availability processors</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=2" title="Edit section: 3B high-availability processors"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The original series of 3B computers includes the models 3B20C, 3B20D,<sup id="cite_ref-3Bseries.NYT840328_1-2" class="reference"><a href="#cite_note-3Bseries.NYT840328-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> 3B21D, and 3B21E. </p><p>These systems are 32-bit <a href="/wiki/Microcode" title="Microcode">microprogrammed</a> duplex (<a href="/wiki/Redundancy_(engineering)" title="Redundancy (engineering)">redundant</a>) <a href="/wiki/High_availability" title="High availability">high availability</a> processor units running a <a href="/wiki/Real-time_operating_system" title="Real-time operating system">real-time operating system</a>. They were first produced in the late 1970s at the <a href="/wiki/Western_Electric" title="Western Electric">Western Electric</a> factory in <a href="/wiki/Lisle,_Illinois" title="Lisle, Illinois">Lisle, Illinois</a>, for telecommunications applications including the <a href="/wiki/No._4_Electronic_Switching_System" title="No. 4 Electronic Switching System">4ESS</a> and <a href="/wiki/5ESS_Switching_System" title="5ESS Switching System">5ESS</a> systems. </p><p>They use the Duplex Multi Environment Real Time (<a href="/wiki/DMERT" class="mw-redirect" title="DMERT">DMERT</a>) operating system which was renamed <a href="/wiki/UNIX-RTR" class="mw-redirect" title="UNIX-RTR">UNIX-RTR</a> (Real Time Reliable) in 1982. The Data Manipulation Unit (DMU) provides arithmetic and logic operations on 32-bit words using eight <a href="/wiki/AMD_Am2900" title="AMD Am2900">AMD 2901</a> 4-bit-slice <a href="/wiki/Arithmetic_logic_unit" title="Arithmetic logic unit">ALUs</a>.<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> The first 3B20D is called the Model 1. Each processor's control unit consists of two frames of circuit packs. The whole duplex system requires seven-foot frames of circuit packs plus at least one tape drive frame (most telephone companies at that time wrote billing data on <a href="/wiki/Magnetic_tapes" class="mw-redirect" title="Magnetic tapes">magnetic tapes</a>), and many <a href="/wiki/Washing_machine" title="Washing machine">washing machine</a>-sized disk drives. For training and lab purposes, a 3B20D can be divided into two "half-duplex" systems. A 3B20S consists of most of the same hardware as a half-duplex but uses a completely different operating system. </p><p>The 3B20C was briefly available as a high-availability fault tolerant <a href="/wiki/Multiprocessing" title="Multiprocessing">multiprocessing</a> general-purpose computer in the commercial market in 1984. The 3B20E was created to provide a cost-reduced 3B20D for small offices that did not expect such high availability. It consists of a virtual "emulated" 3B20D environment running on a stand-alone general purpose computer; the system was ported to many computers, but primarily runs on the <a href="/wiki/Sun_Microsystems" title="Sun Microsystems">Sun Microsystems</a> <a href="/wiki/Solaris_(operating_system)" class="mw-redirect" title="Solaris (operating system)">Solaris</a> environment. </p><p>There were improvements to the 3B20D UNIX-RTR system in both software and hardware in the 1980s, 1990s, 2000s, and 2010s. Innovations included disk independent operation (DIOP: the ability to continue essential software processing such as telecommunications after duplex failure of redundant essential disks); off-line boot (the ability to split in half and boot the out-of-service half, typically on a new software release) and switch forward (switch processing to the previously out-of-service half); upgrading the disks to <a href="/wiki/Solid-state_drive" title="Solid-state drive">solid-state drive</a> (SSD) ; and upgrading the tape unit to <a href="/wiki/CompactFlash" title="CompactFlash">CompactFlash</a>. </p><p>The processor was re-engineered and renamed in 1992 as the 3B21D. It is still in use as of 2023<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=3B_series_computers&action=edit">[update]</a></sup> as a component of <a href="/wiki/Nokia" title="Nokia">Nokia</a> products such as the <a href="/w/index.php?title=2STP&action=edit&redlink=1" class="new" title="2STP (page does not exist)">2STP</a> <a href="/wiki/Signal_Transfer_Point" title="Signal Transfer Point">signal transfer point</a> and the 4ESS and 5ESS switches, which Nokia inherited from AT&T spin-off <a href="/wiki/Lucent_Technologies" title="Lucent Technologies">Lucent Technologies</a>. </p> <div class="mw-heading mw-heading2"><h2 id="Minicomputers">Minicomputers</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=3" title="Edit section: Minicomputers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="3B20S">3B20S</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=4" title="Edit section: 3B20S"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 3B20S (simplex) was developed at <a href="/wiki/Bell_Labs" title="Bell Labs">Bell Labs</a> and produced by Western Electric in 1982 for general purpose internal <a href="/wiki/Bell_System" title="Bell System">Bell System</a> use. The 3B20S<sup id="cite_ref-3Bseries.NYT840328_1-3" class="reference"><a href="#cite_note-3Bseries.NYT840328-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> has hardware similar to the 3B20D, but one unit instead of two. The machine is approximately the size of a large <a href="/wiki/Refrigerator" title="Refrigerator">refrigerator</a>, requiring a minimum of 170 square feet floor space.<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> It was in use at the <a href="/wiki/1984_Summer_Olympics" title="1984 Summer Olympics">1984 Summer Olympics</a>, where around twelve 3B20S served the <a href="/wiki/Email" title="Email">email</a> requirements of the <i>Electronic Messaging System</i>, which was built to replace the man-based messaging system of earlier Olympiads. The system connected around 1800 user terminals and 200 printers.<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> The <b>3B20A</b> is an enhanced version of the 3B20S, adding in a second processing unit working in parallel as a multiprocessor unit. </p> <div class="mw-heading mw-heading3"><h3 id="3B5">3B5</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=5" title="Edit section: 3B5"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 3B5 is built with the older Western Electric <a href="/wiki/Bellmac_32" title="Bellmac 32">WE 32000</a> 32-bit microprocessor. The initial versions have discrete memory management unit hardware using gate arrays, and support segment-based memory translation. I/O is programmed using memory-mapped techniques. The machine is approximately the size of a <a href="/wiki/Dishwasher" title="Dishwasher">dishwasher</a>, though adding the reel-to-reel tape drive increases its size. These computers use <a href="/wiki/Storage_Module_Device" title="Storage Module Device">SMD</a> hard drives. </p> <div class="mw-heading mw-heading3"><h3 id="3B15">3B15</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=6" title="Edit section: 3B15"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 3B15, introduced in 1985,<sup id="cite_ref-unixreviewdec85_11-0" class="reference"><a href="#cite_note-unixreviewdec85-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> uses the WE 32100 and is the faster follow-on to the 3B5 with similar large form factor. </p> <div class="mw-heading mw-heading3"><h3 id="3B4000">3B4000</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=7" title="Edit section: 3B4000"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The 3B4000 is a <a href="/wiki/High_availability" title="High availability">high availability</a> server introduced in 1987<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> and based on a 'snugly-coupled' architecture using the WE series 32x00 32-bit processor. Known internally as 'Apache', the 3B4000 is a follow-on to the 3B15 and initial revisions use a 3B15 as a master processor. Developed in the mid-1980's at the <a href="/wiki/Lisle,_Illinois" title="Lisle, Illinois">Lisle</a> Indian Hill West facility by the High Performance Computer Development Lab, the system consists of multiple high performance (at the time) processor boards – adjunct processing elements (APEs) and adjunct communication elements (ACEs). These adjunct processors run a customized UNIX kernel with drivers for SCSI (APEs) and serial boards (ACEs). The processing boards are interconnected by a redundant low latency parallel bus (ABUS) running at 20 MB/s. The UNIX kernels running on the adjunct processors are modified to allow the fork/exec of processes across processing units. The system calls and peripheral drivers are also extended to allow processes to access remote resources across the ABUS. Since the ABUS is hot-swappable, processors can be added or replaced without shutting down the system. If one of the adjunct processors fails during operation, the system can detect and restart programs that were running on the failed element. </p><p>The 3B4000 is capable of significant expansion; one test system (including storage) occupies 17 mid-height cabinets. Generally, the performance of the system increases linearly with additional processing elements, however the lack of a true <a href="/wiki/Shared_memory" title="Shared memory">shared memory</a> capability requires rewriting applications that rely heavily on this feature to avoid a severe performance penalty. </p> <div class="mw-heading mw-heading2"><h2 id="Microcomputers">Microcomputers</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=8" title="Edit section: Microcomputers"><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:3B2_model_400_sitting_on_grass.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/3B2_model_400_sitting_on_grass.jpg/220px-3B2_model_400_sitting_on_grass.jpg" decoding="async" width="220" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/3B2_model_400_sitting_on_grass.jpg/330px-3B2_model_400_sitting_on_grass.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/ff/3B2_model_400_sitting_on_grass.jpg/440px-3B2_model_400_sitting_on_grass.jpg 2x" data-file-width="3872" data-file-height="2592" /></a><figcaption>A 3B2 model 400</figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="3B2">3B2</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=9" title="Edit section: 3B2"><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:3b2-300-motherboard.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3d/3b2-300-motherboard.jpg/220px-3b2-300-motherboard.jpg" decoding="async" width="220" height="119" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3d/3b2-300-motherboard.jpg/330px-3b2-300-motherboard.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3d/3b2-300-motherboard.jpg/440px-3b2-300-motherboard.jpg 2x" data-file-width="2844" data-file-height="1536" /></a><figcaption>3B2/300 motherboard</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:3b2-vme.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/3b2-vme.jpg/220px-3b2-vme.jpg" decoding="async" width="220" height="110" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/3b2-vme.jpg/330px-3b2-vme.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/59/3b2-vme.jpg/440px-3b2-vme.jpg 2x" data-file-width="2858" data-file-height="1430" /></a><figcaption>WE 321SB VMEbus Single Board Computer</figcaption></figure> <p>The 3B2 was introduced in 1984 using the <a href="/wiki/Bellmac_32" title="Bellmac 32">WE 32000</a> 32-bit microprocessor at 8 MHz with memory management chips that supports <a href="/wiki/Demand_paging" title="Demand paging">demand paging</a>. Uses include the <a href="/wiki/Switching_Control_Center_System" title="Switching Control Center System">Switching Control Center System</a>. The 3B2 Model 300, which can support up to 18 users,<sup id="cite_ref-3Bseries.NYT840328_1-4" class="reference"><a href="#cite_note-3Bseries.NYT840328-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> is approximately 4 inches (100 mm) high and the 3B2 Model 400 is approximately 8 inches (200 mm) high. </p><p>The 300 was soon supplanted by the 3B2/310 running at 10 MHz, which features the WE 32100 CPU as do later models. The Model 400, introduced in 1985,<sup id="cite_ref-unixreviewdec85_11-1" class="reference"><a href="#cite_note-unixreviewdec85-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> allows more peripheral slots and more memory, and has a built-in 23 MB <a href="/wiki/Quarter-inch_cartridge" title="Quarter-inch cartridge">QIC</a> tape drive managed by a <a href="/wiki/Floppy_disk_controller" class="mw-redirect" title="Floppy disk controller">floppy disk controller</a> (nicknamed the "floppy tape"). These three models use standard <a href="/wiki/Modified_Frequency_Modulation" class="mw-redirect" title="Modified Frequency Modulation">MFM</a> <style data-mw-deduplicate="TemplateStyles:r1154941027">.mw-parser-output .frac{white-space:nowrap}.mw-parser-output .frac .num,.mw-parser-output .frac .den{font-size:80%;line-height:0;vertical-align:super}.mw-parser-output .frac .den{vertical-align:sub}.mw-parser-output .sr-only{border:0;clip:rect(0,0,0,0);clip-path:polygon(0px 0px,0px 0px,0px 0px);height:1px;margin:-1px;overflow:hidden;padding:0;position:absolute;width:1px}</style><span class="frac">5<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">4</span></span>" hard disk drives. </p><p>There are also Model 100 and Model 200 3B2 systems.<sup id="cite_ref-3Bseries.NYT840328_1-5" class="reference"><a href="#cite_note-3Bseries.NYT840328-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>The 3B2/600,<sup id="cite_ref-3B2.600NYT870325_3-1" class="reference"><a href="#cite_note-3B2.600NYT870325-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> running at 18 MHz, offers an improvement in performance and capacity: it features a <a href="/wiki/SCSI" title="SCSI">SCSI</a> controller for the 60 MB QIC tape and two internal full-height disk drives. The 600 is approximately twice as tall as a 400, and is oriented with the tape and floppy disk drives opposite the backplane (instead of at a right angle to it as on the 3xx, 4xx and later 500 models). Early models use an internal <a href="/wiki/Emulex" title="Emulex">Emulex</a> card to interface the SCSI controller with ESDI disks, with later models using SCSI drives directly. </p><p>The 3B2/500 was the next model to appear, essentially a 3B2/600 with enough components removed to fit into a 400 case; one internal disk drive and several backplane slots are sacrificed in this conversion. Unlike the 600, which because of its two large fans is loud, the 500 is tolerable in an office environment, like the 400.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (July 2022)">citation needed</span></a></i>]</sup> </p><p>The 3B2/700<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> is an uprated version of the 600 featuring a slightly faster processor (WE 32200 at 22 MHz), and the 3B2/1000<sup id="cite_ref-3Bseries.RoyNYT890316_2-1" class="reference"><a href="#cite_note-3Bseries.RoyNYT890316-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> is an additional step in this direction (WE 32200 at 24 MHz). </p> <div class="mw-heading mw-heading3"><h3 id="3B1_desktop_workstation">3B1 desktop workstation</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=10" title="Edit section: 3B1 desktop workstation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Officially named the <i><a href="/wiki/AT%26T_UNIX_PC" title="AT&T UNIX PC">AT&T UNIX PC</a></i>,<sup id="cite_ref-3B1_14-0" class="reference"><a href="#cite_note-3B1-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> AT&T introduced a <a href="/wiki/Desktop_computer" title="Desktop computer">desktop computer</a> in 1985 that is often dubbed the <i>3B1</i>. However, this <a href="/wiki/Workstation" title="Workstation">workstation</a> is unrelated in hardware to the 3B line, and is based on the <a href="/wiki/Motorola_68010" title="Motorola 68010">Motorola 68010</a> microprocessor. It runs a derivative of Unix System V Release 2 by <a href="/wiki/Convergent_Technologies" title="Convergent Technologies">Convergent Technologies</a>. The system, which is also known as the <i>PC-7300</i>, is tailored for use as a productivity tool in office environments and as an electronic communication center.<sup id="cite_ref-3B1_14-1" class="reference"><a href="#cite_note-3B1-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=3B_series_computers&action=edit&section=11" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Altos_Computer_Systems" title="Altos Computer Systems">Altos Computer Systems</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=3B_series_computers&action=edit&section=12" 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-3Bseries.NYT840328-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-3Bseries.NYT840328_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-3Bseries.NYT840328_1-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-3Bseries.NYT840328_1-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-3Bseries.NYT840328_1-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-3Bseries.NYT840328_1-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-3Bseries.NYT840328_1-5"><sup><i><b>f</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 id="CITEREFAndrew_Pollack1984" class="citation news cs1">Andrew Pollack (March 28, 1984). <a 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March 16, 1989.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=A.T.%26T.+Addition+To+Computer+Line&rft.date=1989-03-16&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1989%2F03%2F16%2Fbusiness%2Fcompany-news-at-t-addition-to-computer-line.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" class="Z3988"></span></span> </li> <li id="cite_note-3B2.600NYT870325-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-3B2.600NYT870325_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-3B2.600NYT870325_3-1"><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 news cs1"><a rel="nofollow" class="external text" href="https://www.nytimes.com/1987/03/25/business/company-news-digital-introduces-computer-series.html">"Digital Introduces Computer Series"</a>. <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i>. March 25, 1987.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=Digital+Introduces+Computer+Series&rft.date=1987-03-25&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1987%2F03%2F25%2Fbusiness%2Fcompany-news-digital-introduces-computer-series.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" class="Z3988"></span></span> </li> <li id="cite_note-3B2.HC84-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-3B2.HC84_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWalter_Zintz1984" class="citation magazine cs1">Walter Zintz (July 1984). "The Unix Connection: 3B2". <i><a href="/wiki/HARDCOPY" class="mw-redirect" title="HARDCOPY">HARDCOPY</a></i>. p. 142.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=HARDCOPY&rft.atitle=The+Unix+Connection%3A+3B2&rft.pages=142&rft.date=1984-07&rft.au=Walter+Zintz&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" class="Z3988"></span></span> </li> <li id="cite_note-:0-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-:0_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:0_5-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMankowski1984" class="citation news cs1">Mankowski, Cal (March 27, 1984). <a rel="nofollow" class="external text" href="https://www.upi.com/Archives/1984/03/27/ATT-introduces-new-computer-line/5640449211600/">"AT&T introduces new computer line"</a>. <i>UPI</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=UPI&rft.atitle=AT%26T+introduces+new+computer+line&rft.date=1984-03-27&rft.aulast=Mankowski&rft.aufirst=Cal&rft_id=https%3A%2F%2Fwww.upi.com%2FArchives%2F1984%2F03%2F27%2FATT-introduces-new-computer-line%2F5640449211600%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" class="Z3988"></span></span> </li> <li id="cite_note-unixreview198802_olivetti-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-unixreview198802_olivetti_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-unixreview198802_olivetti_6-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFaden1988" class="citation magazine cs1">Faden, Michael (February 1988). <a rel="nofollow" class="external text" href="https://archive.org/details/sim_unix-review_1988-02_6_2/page/9/mode/1up">"Olivetti: Biting the Hand that Feeds It?"</a>. <i>UNIX Review</i>. pp. 14, 16, 20, 22–23<span class="reference-accessdate">. Retrieved <span class="nowrap">August 17,</span> 2022</span> – via Internet Archive.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=UNIX+Review&rft.atitle=Olivetti%3A+Biting+the+Hand+that+Feeds+It%3F&rft.pages=14%2C+16%2C+20%2C+22-23&rft.date=1988-02&rft.aulast=Faden&rft.aufirst=Michael&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fsim_unix-review_1988-02_6_2%2Fpage%2F9%2Fmode%2F1up&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" class="Z3988"></span></span> </li> <li id="cite_note-lastunits-7"><span class="mw-cite-backlink">^ <a href="#cite_ref-lastunits_7-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-lastunits_7-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDenton1993" class="citation news cs1">Denton, Jon (December 16, 1993). <a rel="nofollow" class="external text" href="https://www.oklahoman.com/story/news/1993/12/16/att-makes-last-3b2-city-produced-computer-stuff-of-legends/62439711007/">"AT&T Makes Last 3B2 City-Produced Computer Stuff of Legends"</a>. The Oklahoman.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=AT%26T+Makes+Last+3B2+City-Produced+Computer+Stuff+of+Legends&rft.date=1993-12-16&rft.aulast=Denton&rft.aufirst=Jon&rft_id=https%3A%2F%2Fwww.oklahoman.com%2Fstory%2Fnews%2F1993%2F12%2F16%2Fatt-makes-last-3b2-city-produced-computer-stuff-of-legends%2F62439711007%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" 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">J. O. Becker, The 3B20D PROCESSOR and DMERT Operating System (The Bell System Technical Journal, January 1983, Vol. 62, No. 1, Part 1), Page 193</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"><a rel="nofollow" class="external text" href="http://bitsavers.trailing-edge.com/pdf/westernElectric/3b20s/234-301-910WE_3B20S_System_Index_and_Description_Jul81.pdf">3B20S Processor System Index and Description</a>, Western Electric Co., July 1981.</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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation journal cs1"><a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/document/1654251">"Olympics electronic messaging system demonstrated"</a>. <i><a href="/wiki/IEEE_Computer" class="mw-redirect" title="IEEE Computer">IEEE Computer</a></i>. <b>16</b> (11): 113. November 1983. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMC.1983.1654251">10.1109/MC.1983.1654251</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:47105018">47105018</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Computer&rft.atitle=Olympics+electronic+messaging+system+demonstrated&rft.volume=16&rft.issue=11&rft.pages=113&rft.date=1983-11&rft_id=info%3Adoi%2F10.1109%2FMC.1983.1654251&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A47105018%23id-name%3DS2CID&rft_id=https%3A%2F%2Fieeexplore.ieee.org%2Fdocument%2F1654251&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" class="Z3988"></span></span> </li> <li id="cite_note-unixreviewdec85-11"><span class="mw-cite-backlink">^ <a href="#cite_ref-unixreviewdec85_11-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-unixreviewdec85_11-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChandler1985" class="citation magazine cs1">Chandler, David (December 1985). <a rel="nofollow" class="external text" href="https://archive.org/details/Unix_Review_1985_Dec.pdf/page/n9/mode/1up">"The Monthly Report"</a>. <i>Unix Review</i>. p. 8.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Unix+Review&rft.atitle=The+Monthly+Report&rft.pages=8&rft.date=1985-12&rft.aulast=Chandler&rft.aufirst=David&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2FUnix_Review_1985_Dec.pdf%2Fpage%2Fn9%2Fmode%2F1up&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" 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 id="CITEREFCalvin_Sims1987" class="citation news cs1">Calvin Sims (September 3, 1987). <a rel="nofollow" class="external text" href="https://www.nytimes.com/1987/09/03/business/computers-introduced-at-at-t.html">"Computers Introduced At A.T.&T"</a>. <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=Computers+Introduced+At+A.T.%26T.&rft.date=1987-09-03&rft.au=Calvin+Sims&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1987%2F09%2F03%2Fbusiness%2Fcomputers-introduced-at-at-t.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" 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 news cs1"><a rel="nofollow" class="external text" href="https://www.nytimes.com/1988/05/10/business/company-news-at-t-displays-midsize-computer.html">"A.T.&T. Displays Midsize Computer"</a>. <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i>. May 10, 1988. <q>could support up to 80 users</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=A.T.%26T.+Displays+Midsize+Computer&rft.date=1988-05-10&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1988%2F05%2F10%2Fbusiness%2Fcompany-news-at-t-displays-midsize-computer.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3A3B+series+computers" class="Z3988"></span></span> </li> <li id="cite_note-3B1-14"><span class="mw-cite-backlink">^ <a href="#cite_ref-3B1_14-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-3B1_14-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">AT&T, Select Code 999-601-311IS, <i>AT&T UNIX PC Owner's Manual</i> (1986)</span> </li> </ol></div></div> <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=3B_series_computers&action=edit&section=13" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.hartetechnologies.com/manuals/3b2/">3B2 manuals</a> at Harte Technologies</li> <li><a rel="nofollow" class="external text" href="http://www.unixwiz.net/3b2.html">AT&T 3B2/3B5 Computer Systems</a> at Unixwiz.net</li> <li><a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=ZLwd32muHwM"><span class="plainlinks">AT&T 3B2 400 Computer Review</span></a> on <a href="/wiki/YouTube_video_(identifier)" class="mw-redirect" title="YouTube video (identifier)">YouTube</a> by TanRu Nomad in 2012</li> <li><a rel="nofollow" class="external text" href="https://loomcom.com/3b2/emulator/">3B2 Emulator</a> by Seth J. Morabito</li></ul> <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 ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist 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