{"id":22102,"date":"2025-08-21T09:41:56","date_gmt":"2025-08-21T13:41:56","guid":{"rendered":"https:\/\/carleton.ca\/scs\/?page_id=22102"},"modified":"2026-06-22T14:51:06","modified_gmt":"2026-06-22T18:51:06","slug":"vin109","status":"publish","type":"page","link":"https:\/\/carleton.ca\/scs\/vintage-computing\/item\/vin109\/","title":{"rendered":"Tandy TRS-80 Model II"},"content":{"rendered":"\n<section class=\"w-screen px-6 cu-section cu-section--white ml-offset-center md:px-8 lg:px-14\">\n    <div class=\"space-y-6 cu-max-w-child-5xl  md:space-y-10 cu-prose-first-last\">\n\n            <div class=\"cu-textmedia flex flex-col lg:flex-row mx-auto gap-6 md:gap-10 my-6 md:my-12 first:mt-0 max-w-5xl\">\n        <div class=\"justify-start cu-textmedia-content cu-prose-first-last\" style=\"flex: 0 0 100%;\">\n            <header class=\"font-light prose-xl cu-pageheader md:prose-2xl cu-component-updated cu-prose-first-last\">\n                                    <h1 class=\"cu-prose-first-last font-semibold !mt-2 mb-4 md:mb-6 relative after:absolute after:h-px after:bottom-0 after:bg-cu-red after:left-px text-3xl md:text-4xl lg:text-5xl lg:leading-[3.5rem] pb-5 after:w-10 text-cu-black-700 not-prose\">\n                        Tandy TRS-80 Model II\n                    <\/h1>\n                \n                                \n                            <\/header>\n\n                    <\/div>\n\n            <\/div>\n\n    <\/div>\n<\/section>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button is-style-fill\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/carleton.ca\/scs\/vintage-computing\/item\">Vintage Computing Collection<\/a><\/div>\n<\/div>\n\n\n\n<h2 id=\"tandy-trs-80-model-ii\" class=\"wp-block-heading\">Tandy TRS-80 Model II<\/h2>\n\n\n\n<p>[Vin109]<\/p>\n\n\n\n<figure class=\"wp-block-image alignright\"><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-scaled.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"400\" height=\"300\" src=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-400x300.jpg\" alt=\"TRS-80 Model II\" class=\"wp-image-23245\" srcset=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-400x300.jpg 400w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-160x120.jpg 160w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-240x180.jpg 240w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-768x577.jpg 768w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-1536x1153.jpg 1536w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-2048x1538.jpg 2048w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-800x600.jpg 800w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20260114_145902372-360x270.jpg 360w\" sizes=\"auto, (max-width: 400px) 100vw, 400px\" \/><\/a><\/figure>\n\n\n\n<p>The Radio Shack TRS-80 Model II, launched in October 1979, was a notable vintage computer designed specifically for the small-business market rather than personal or hobbyist use. It featured a high-speed 4 MHz Z80A processor, Direct Memory Access (DMA), vectored interrupts, a built-in 12-inch 80&#215;25 text display, and a unique architecture with a detachable keyboard and multiple expansion slots, making it well-suited for business tasks like accounting and word processing. Its claim to fame was being a professional-grade business machine from a company known for hobbyist computers, offering advanced features at a lower price compared to contemporaries like IBM systems. While it was respected for its design and expandability, it remained less popular than the earlier TRS-80 Model I in home and hobbyist markets, partly due to its focus on business and a smaller software library.<\/p>\n\n\n\n<p>&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Manufacturer<\/strong>: Tandy Corporation (sold through Radio Shack stores)<\/li>\n\n\n\n<li><strong>Type<\/strong>: Personal computer<\/li>\n\n\n\n<li><strong>Released<\/strong>: 1979<\/li>\n\n\n\n<li><strong>Cost at release (base price)<\/strong>: USD $3,450 (CAD ~$16,000 adjusted for inflation)<\/li>\n\n\n\n<li><strong>Cost at release (with peripherals)<\/strong>: USD $4,898 (CAD ~$23,000 adjusted for inflation)<\/li>\n\n\n\n<li><strong>MIPS<\/strong>: 0.33&nbsp; (330 KIPS)<\/li>\n<\/ul>\n\n\n\n<h3 id=\"hardware-specifications\" class=\"wp-block-heading\"><span class=\"NormalTextRun SCXW169789978 BCX0\">Hardware Specifications<\/span><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>CPU<\/strong>: Zilog Z80A running at 4 MHz<\/li>\n\n\n\n<li><strong>Memory<\/strong>: Standard 32 KB or optionally 64 KB RAM<\/li>\n\n\n\n<li><strong>Display<\/strong>: Built-in 12-inch CRT monitor with 80&#215;25 character text display<\/li>\n\n\n\n<li><strong>Storage<\/strong>: Used 8-inch floppy disk drives (dual floppy drives common)<\/li>\n\n\n\n<li><strong>Keyboard<\/strong>: Full-stroke detachable keyboard with numeric keypad<\/li>\n\n\n\n<li><strong>Expansion<\/strong>: Multiple internal expansion slots for peripheral cards<\/li>\n\n\n\n<li><strong>Input\/Output<\/strong>: Serial and parallel ports for printers and other peripherals<\/li>\n\n\n\n<li><strong>Additional features<\/strong>: Direct Memory Access (DMA), vectored interrupts<\/li>\n\n\n\n<li><strong>Weight<\/strong>: ~13.6 kg (30 lbs)<\/li>\n<\/ul>\n\n\n\n<h3 id=\"operating-system-programming-languages\" class=\"wp-block-heading\"><span class=\"TextRun SCXW50331614 BCX0\" lang=\"EN-US\" xml:lang=\"EN-US\" data-contrast=\"auto\"><span class=\"NormalTextRun SCXW50331614 BCX0\">Operating System &amp; Programming Languages<\/span><\/span><span class=\"EOP SCXW50331614 BCX0\" data-ccp-props=\"{&quot;335559685&quot;:0}\">&nbsp;<\/span><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>O\/S<\/strong>:&nbsp; primarily ran the operating system called&nbsp;<strong>TRSDOS-2<\/strong>, a disk-based OS designed specifically for business use. Later, it also supported&nbsp;<strong>CP\/M<\/strong><\/li>\n\n\n\n<li><strong>Programming Languages<\/strong>: BASIC (Business BASIC was common for business-related programming), BASCOM (a form of BASIC compiler), COBOL (used widely for business applications), FORTRAN, Assembly language (Zilog Z80 assembly) for more advanced and performance-sensitive programming, Pascal was also available through third-party vendors<\/li>\n<\/ul>\n\n\n\n<h3 id=\"notables\" class=\"wp-block-heading\">Notables<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The TRS-80 Model II was the first TRS-80 designed specifically as a small-business computer, not a hobbyist machine.<\/li>\n\n\n\n<li>It featured Direct Memory Access (DMA) and vectored interrupts, advanced features uncommon in early personal computers.<\/li>\n\n\n\n<li>Nicknamed sometimes as the &#8220;business TRS-80,&#8221; it was positioned to compete with more expensive systems like IBM PCs but at a lower cost.<\/li>\n\n\n\n<li>It was among the earliest microcomputers to include a built-in 80-column by 25-line text display, suited for professional applications.<\/li>\n\n\n\n<li>Unlike the original Model I, the Model II had a detachable keyboard, which was unusual for its time.<\/li>\n\n\n\n<li>It helped popularize business use of microcomputers before the IBM PC&#8217;s dominance.<\/li>\n\n\n\n<li>The Model II&#8217;s architecture paved the way for more advanced Tandy business systems such as the TRS-80 Model 12 and 16.<\/li>\n\n\n\n<li>The Model II was not as popular as the Model I among hobbyists, but highly respected in business computing history and vintage computing museums for its professional focus and technical innovations.<\/li>\n<\/ul>\n\n\n\n<p><strong>Donated by<\/strong>: Engineer working for National Defense and worked on the Avro Aero and also worked on some rocket engines and used this computer during his time at National Defense.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button is-style-fill\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/carleton.ca\/scs\/vintage-computing\/item\">Vintage Computing Collection<\/a><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Tandy TRS-80 Model II [Vin109] The Radio Shack TRS-80 Model II, launched in October 1979, was a notable vintage computer designed specifically for the small-business market rather than personal or hobbyist use. It featured a high-speed 4 MHz Z80A processor, Direct Memory Access (DMA), vectored interrupts, a built-in 12-inch 80&#215;25 text display, and a unique [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":19704,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_cu_dining_location_slug":"","footnotes":"","_links_to":"","_links_to_target":""},"cu_page_type":[90,123],"class_list":["post-22102","page","type-page","status-publish","hentry","cu_page_type-vintage-computing","cu_page_type-vintage-inventory"],"acf":{"cu_post_thumbnail":""},"_links":{"self":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/22102","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/comments?post=22102"}],"version-history":[{"count":4,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/22102\/revisions"}],"predecessor-version":[{"id":25138,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/22102\/revisions\/25138"}],"up":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/19704"}],"wp:attachment":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/media?parent=22102"}],"wp:term":[{"taxonomy":"cu_page_type","embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/cu_page_type?post=22102"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}