{"id":19865,"date":"2024-11-07T14:01:00","date_gmt":"2024-11-07T19:01:00","guid":{"rendered":"https:\/\/carleton.ca\/scs\/?page_id=19865"},"modified":"2026-02-10T16:24:02","modified_gmt":"2026-02-10T21:24:02","slug":"vin4","status":"publish","type":"page","link":"https:\/\/carleton.ca\/scs\/vintage-computing\/item\/vin4\/","title":{"rendered":"Cromenco System Three"},"content":{"rendered":"<h2>Cromenco System Three<\/h2>\n<p>[Vin4]<\/p>\n<p><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/first-place-400x400-1.png\"><img decoding=\"async\" loading=\"lazy\" class=\"alignleft wp-image-21940\" src=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/first-place-400x400-1-160x160.png\" alt=\"First Ever icon\" width=\"117\" height=\"117\" srcset=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/first-place-400x400-1-160x160.png 160w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/first-place-400x400-1-240x240.png 240w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/first-place-400x400-1-200x200.png 200w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/first-place-400x400-1-360x360.png 360w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/first-place-400x400-1.png 400w\" sizes=\"(max-width: 117px) 100vw, 117px\" \/><\/a>The Cromemco System Three, introduced in 1979, was a high-end, rack-mounted microcomputer featuring a robust S-100 bus architecture with a 21-slot motherboard, allowing substantial expansion. It ran a Z-80A CPU at 4 MHz, with some models optionally including a Motorola 68000, supporting multi-user operation via the UNIX-like CROMIX OS. Its memory expandable up to 4 MB, dual 8-inch floppy drives, and professional usage made it popular in military and broadcast environments. Notably, the System Three supported the Cromemco Dazzler, introduced in 1976, the world&#8217;s first colour graphics card for microcomputers. The Dazzler produced composite NTSC video output, enabling color displays on TVs and monitors, which was groundbreaking at the time and helped drive Cromemco systems into television broadcast and other graphical applications.<\/p>\n<p><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-scaled.jpg\"><img decoding=\"async\" loading=\"lazy\" class=\"alignright size-large wp-image-21458\" src=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-400x300.jpg\" alt=\"Cromenco System Three\" width=\"400\" height=\"300\" srcset=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-400x300.jpg 400w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-240x180.jpg 240w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-160x120.jpg 160w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-768x577.jpg 768w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-1536x1153.jpg 1536w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-2048x1538.jpg 2048w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-800x600.jpg 800w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250624_192338914-360x270.jpg 360w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><\/a><\/p>\n<ul>\n<li><strong>Manufacturer<\/strong>: Cromenco Inc.<\/li>\n<li><strong>Type<\/strong>: Rack-mount microcomputer<\/li>\n<li><strong>Release Date<\/strong>: 1979<\/li>\n<li><strong>Cost at release<\/strong>: USD $5,990 (CAD ~$28,000 adjusted for inflation)<\/li>\n<li><strong>Cost with peripherals<\/strong>: USD $12,495 (CAD ~$59,000 adjusted for inflation)<\/li>\n<li><strong>MIPS<\/strong>: 0.58-0.8 (580 &#8211; 800 KIPS)<\/li>\n<\/ul>\n<div class=\"slideme\"><dl class=\"slideme__list\"><dt class=\"slideme__term\"><a href=\"#slideme-hardware-specifications\" aria-expanded=\"false\" aria-controls=\"slideme-hardware-specifications\" class=\"slideme__heading slideme__trigger\">Hardware Specifications<\/a><\/dt><dd class=\"slideme__description\" id=\"slideme-hardware-specifications\" aria-hidden=\"true\"><p><\/p>\n<ul>\n<li><strong>CPU<\/strong>: Z-80A @ 4MHz, dual-processor option (Z-80A and Motorola 68000)<\/li>\n<li><strong>RAM<\/strong>: 64K &#8211; 512K<\/li>\n<li><strong>Storage<\/strong>: Dual 8-inch floppy disk drives<\/li>\n<li><strong>Display<\/strong>: Text on RS-232 terminal<\/li>\n<li><strong>Ports<\/strong>: 1 parallel for printer<\/li>\n<\/ul>\n<p><\/p><\/dd><dl><\/div>\n<div class=\"slideme\"><dl class=\"slideme__list\"><dt class=\"slideme__term\"><a href=\"#slideme-operating-system-programming-languages\" aria-expanded=\"false\" aria-controls=\"slideme-operating-system-programming-languages\" class=\"slideme__heading slideme__trigger\">Operating System &amp; Programming Languages<\/a><\/dt><dd class=\"slideme__description\" id=\"slideme-operating-system-programming-languages\" aria-hidden=\"true\"><p><\/p>\n<ul>\n<li><strong>OS<\/strong>: Cromemco CDOS or CROMIX, Cromemco CDOS (CP\/M-compatible) and CROMIX (UNIX-like)<\/li>\n<li><strong>Programming Languages<\/strong>: FORTRAN 77, C, Pascal, COBOL, BASIC, RATFOR, LISP, RPG-I, Macro Assembler<\/li>\n<\/ul>\n<p><\/p><\/dd><dl><\/div>\n<div class=\"slideme\"><dl class=\"slideme__list\"><dt class=\"slideme__term\"><a href=\"#slideme-notables\" aria-expanded=\"false\" aria-controls=\"slideme-notables\" class=\"slideme__heading slideme__trigger\">Notables<\/a><\/dt><dd class=\"slideme__description\" id=\"slideme-notables\" aria-hidden=\"true\"><p><\/p>\n<ul>\n<li>Cromemco was named after &#8220;Crothers Memorial Hall,&#8221; the Stanford dorm where the founders began their collaboration<\/li>\n<li>The System Three was one of the earliest microcomputers to offer true multi-user capabilities, supporting up to six simultaneous users with its UNIX-like CROMIX operating system<\/li>\n<li>It featured a dual-processor option (Z-80A and Motorola 68000), making it unusually powerful and flexible for its era<\/li>\n<li>The System Three was not a desktop machine but a heavy, rack-mountable system intended for professional and institutional environments<\/li>\n<li>Cromemco computers, including the System Three, were widely used by the U.S. military, notably the Air Force and Navy, and were deployed in critical applications such as the Mission Support System for fighter aircraft and on Ohio-class submarines<\/li>\n<li>The System Three and its siblings were used in the Chicago Mercantile Exchange for trade processing and in over 80% of major U.S. TV stations for weather and news graphics in the 1980s<\/li>\n<li>Cromemco systems were among the first microcomputers distributed in China, with over 10,000 units sold to universities by 1985<\/li>\n<li>Its place in computing history is as a pioneering, reliable, and expandable microcomputer that bridged the gap between hobbyist systems and robust business\/industrial computing, influencing the evolution of multi-user microcomputers and early UNIX-like systems<\/li>\n<\/ul>\n<p><\/p><\/dd><dl><\/div>\n<p><strong>Donated by<\/strong>: Dr. Arlen Michaels<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Cromenco System Three [Vin4] The Cromemco System Three, introduced in 1979, was a high-end, rack-mounted microcomputer featuring a robust S-100 bus architecture with a 21-slot motherboard, allowing substantial expansion. It ran a Z-80A CPU at 4 MHz, with some models optionally including a Motorola 68000, supporting multi-user operation via the UNIX-like CROMIX OS. Its memory [&hellip;]<\/p>\n","protected":false},"author":7,"featured_media":0,"parent":19704,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_relevanssi_hide_post":"","_relevanssi_hide_content":"","_relevanssi_pin_for_all":"","_relevanssi_pin_keywords":"","_relevanssi_unpin_keywords":"","_relevanssi_related_keywords":"","_relevanssi_related_include_ids":"","_relevanssi_related_exclude_ids":"","_relevanssi_related_no_append":"","_relevanssi_related_not_related":"","_relevanssi_related_posts":"","_relevanssi_noindex_reason":"","_mi_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":"","_links_to":"","_links_to_target":""},"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v21.2 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Cromenco System Three - School of Computer Science<\/title>\n<meta name=\"description\" content=\"Cromenco System Three The Cromemco System Three, introduced in 1979, was a high-end, rack-mounted microcomputer featuring a robust S-100 bus architecture\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/carleton.ca\/scs\/vintage-computing\/item\/vin4\/\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/carleton.ca\/scs\/vintage-computing\/item\/vin4\/\",\"url\":\"https:\/\/carleton.ca\/scs\/vintage-computing\/item\/vin4\/\",\"name\":\"Cromenco System Three - 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