{"id":96259,"date":"2025-08-25T16:27:07","date_gmt":"2025-08-25T16:27:07","guid":{"rendered":"https:\/\/www.newsbeep.com\/ca\/96259\/"},"modified":"2025-08-25T16:27:07","modified_gmt":"2025-08-25T16:27:07","slug":"cerns-large-hadron-collider-runs-on-a-bendix-g-15-in-2025","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ca\/96259\/","title":{"rendered":"CERN\u2019s Large Hadron Collider Runs On A Bendix G-15 In 2025"},"content":{"rendered":"<p>The Bendix G-15 refurbished by [David at Usagi Electric] is well known as the oldest digital computer in North America. The question [David] gets most is \u201cwhat can you do with it?\u201d.\u00a0 Well, as a general-purpose computer, it can do just about anything. He set out to prove it. Can a <a href=\"https:\/\/www.youtube.com\/watch?v=2y0DO8d7Az0\" target=\"_blank\" rel=\"nofollow noopener\">1950s-era vacuum tube computer handle modern physics problems?<\/a> This video was several years in the making, was a journey from [David\u2019s] home base in Texas all the way to CERN\u2019s Large Hadron Collider (LHC) in Switzerland.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"808185\" data-permalink=\"https:\/\/hackaday.com\/2025\/08\/25\/cerns-large-hadron-collider-runs-on-a-bendix-g-15-in-2025\/a-7\/\" data-orig-file=\"https:\/\/hackaday.com\/wp-content\/uploads\/2025\/08\/a.png\" data-orig-size=\"540,168\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"Intercom Command Format\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/08\/a.png\" data-large-file=\"https:\/\/hackaday.com\/wp-content\/uploads\/2025\/08\/a.png?w=540\" class=\"size-medium wp-image-808185 alignright\" src=\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/08\/a.png\" alt=\"Command breakdown\" width=\"400\" height=\"124\"  \/>The G-15 can run several \u201chigh-level\u201d programming languages, including Algol.\u00a0 The most popular, though, was Intercom. Intercom is an interactive programming language \u2013 you can type your program in right at the typewriter. It\u2019s much closer to working with a basic interpreter than, say, a batch-processed IBM 1401 with punched cards. We\u2019re still talking about the 1950s, though, so the language mechanics are quite a bit different from what we\u2019re used to today.<\/p>\n<p>To start with, [Usagi\u2019s] the G-15 is a numeric machine. It can\u2019t even handle the full alphabet. What\u2019s more, all numbers on the G-15 are stored as floating-point values. Commands are sent via operation codes.\u00a0 For example, ADD is operation 43.\u00a0 You have to wrangle an index register and an address as well.\u00a0 Intercom feels a bit like a cross between assembler and tokenized BASIC.<\/p>\n<p>If you\u2019d like to play along, the<a href=\"http:\/\/www.bitsavers.org\/pdf\/bendix\/g-15\/APG-07581-4_Intercom1000_Pgm_Man_Apr61.pdf\" target=\"_blank\" rel=\"nofollow noopener\"> intercom manual is available on Bitsavers<\/a>. (Thanks [Al]!)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"808206\" data-permalink=\"https:\/\/hackaday.com\/2025\/08\/25\/cerns-large-hadron-collider-runs-on-a-bendix-g-15-in-2025\/a_490b6f\/\" data-orig-file=\"https:\/\/hackaday.com\/wp-content\/uploads\/2025\/08\/a_490b6f.png\" data-orig-size=\"1334,1002\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"atlas sim\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/08\/a_490b6f.png\" data-large-file=\"https:\/\/hackaday.com\/wp-content\/uploads\/2025\/08\/a_490b6f.png?w=800\" class=\"alignleft size-medium wp-image-808206\" src=\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/08\/a_490b6f.png\" alt=\"\" width=\"400\" height=\"300\"  \/>In the second half of the video, things take a modern turn. [David\u2019s] friend [Lloyd] recently wrote a high-speed algorithm for the ATLAS detector running at the Large Hadron Collider at CERN.\u00a0 [Lloyd] was instrumental in getting the G-15 up and running.\u00a0 Imagine a career stretching from the early days of computing to modern high-speed data processing. Suffice to say, [Lloyd] is a legend.<\/p>\n<p>There are some hardcore physics and high speed data collection involved in ATLAS. [Allison] from SMU does a great job of explaining it all. The short version is:\u00a0 When particles are smashed together, huge amounts of information is collected by detectors and calorimeters. On the order of 145 TB\/s (yes, TerraBytes per second). It would be impossible to store and analyze all that data. Topoclustering is an algorithm that determines if any given event is important to the researchers or not. The algorithm has to run in less than 1 microsecond, which is why it\u2019s highly pipelined and lives inside an FPGA.<\/p>\n<p>Even though it\u2019s written in Verilog, topoclustering is still an algorithm. This means the G-15, being a general-purpose computer, can run it. To that end, [Lloyd] converted the Verilog code to C. But the Bendix doesn\u2019t run C code. That\u2019s where <a href=\"https:\/\/rbk.delosent.com\/g15doc.html\" target=\"_blank\" rel=\"nofollow noopener\">\u00a0G-15 historian [Rob Kolstad] came in<\/a>. Rob ported the C code to Intercom. [David] punched the program and a sample dataset on a short tape.\u00a0 He loaded up Intercom, then Topoclustering, and sent the run command.\u00a0 The G-15 sprang to life and performed flawlessly, proving that it is a general-purpose computer capable of running modern algorithms.<\/p>\n<\/p>\n<p>Curious about the history of this particular Bendix G-15? Check out <a href=\"https:\/\/hackaday.com\/2024\/12\/21\/the-bendix-g-15-runs-75000-lines-of-code\/\" rel=\"nofollow noopener\" target=\"_blank\">some of our earlier articles<\/a>!<\/p>\n","protected":false},"excerpt":{"rendered":"The Bendix G-15 refurbished by [David at Usagi Electric] is well known as the oldest digital computer in&hellip;\n","protected":false},"author":2,"featured_media":96260,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[24],"tags":[49,48,314,66],"class_list":{"0":"post-96259","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physics","8":"tag-ca","9":"tag-canada","10":"tag-physics","11":"tag-science"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/96259","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=96259"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/96259\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/96260"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=96259"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=96259"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=96259"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}