{"id":21576,"date":"2025-07-08T13:52:27","date_gmt":"2025-07-08T17:52:27","guid":{"rendered":"https:\/\/carleton.ca\/scs\/?page_id=21576"},"modified":"2026-06-22T14:51:53","modified_gmt":"2026-06-22T18:51:53","slug":"vin73","status":"publish","type":"page","link":"https:\/\/carleton.ca\/scs\/vintage-computing\/item\/vin73\/","title":{"rendered":"Texas Instruments TI-99\/4A"},"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                        Texas Instruments TI-99\/4A\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=\"texas-instruments-ti-99-4a\" class=\"wp-block-heading\">Texas Instruments TI-99\/4A<\/h2>\n\n\n\n<p>[Vin73]<\/p>\n\n\n\n<figure class=\"wp-block-image alignright\"><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-scaled.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"400\" height=\"300\" src=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-400x300.jpg\" alt=\"Texas Instruments TI-99\/4A\" class=\"wp-image-21582\" srcset=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-400x300.jpg 400w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-160x120.jpg 160w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-240x180.jpg 240w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-768x577.jpg 768w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-1536x1153.jpg 1536w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-2048x1538.jpg 2048w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-800x600.jpg 800w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250708_181714911-360x270.jpg 360w\" sizes=\"auto, (max-width: 400px) 100vw, 400px\" \/><\/a><\/figure>\n\n\n\n<p>The Texas Instruments TI-99\/4A, launched in 1981, was the world\u2019s first 16-bit home computer, notable for its advanced TMS9900 processor, color graphics, and pioneering speech synthesis peripheral. Its claim to fame lies in introducing 16-bit technology to the home market, influencing later computer architectures and setting a new standard for multimedia capabilities in personal computing. Despite intense competition and a dramatic price war, the TI-99\/4A achieved remarkable popularity with over 2.8 million units sold, becoming a staple in North American households and classrooms.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Manufacturer<\/strong>: Texas Instruments<\/li>\n\n\n\n<li><strong>Released<\/strong>: 1981<\/li>\n\n\n\n<li><strong>Type<\/strong>: Home Computer<\/li>\n\n\n\n<li><strong>Cost at release<\/strong>: USD $525 (CAD ~$2,000 adjusted for inflation)<\/li>\n\n\n\n<li><strong>Cost with peripherals<\/strong>: USD $2,000 (CAD ~$7,850 adjusted for inflation<\/li>\n\n\n\n<li><strong>MIPS<\/strong>: 0.136 (136 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>: Texas Instruments TMS9900, 16-bit, running at 3 MHz<\/li>\n\n\n\n<li><strong>RAM<\/strong>: 256 bytes scratchpad RAM (CPU), 16 KB Video Display Processor (VDP) RAM, expandable up to 52 KB with expansion cards<\/li>\n\n\n\n<li><strong>ROM<\/strong>: 8 KB system ROM, 18 KB GROM (Graphic ROM) for TI BASIC and OS support<\/li>\n\n\n\n<li><strong>Graphics<\/strong>: TMS9918A VDP, supporting 256 \u00d7 192 pixel graphics mode (up to 16 colors)<\/li>\n\n\n\n<li><strong>Sound<\/strong>: TMS9919 sound chip, 3 sound channels plus 1 noise channel (white or periodic), square wave generation from 110 Hz to ~115 kHz<\/li>\n\n\n\n<li><strong>Keyboard<\/strong>: Full-stroke QWERTY keyboard, 48 keys with function, shift, and control keys<\/li>\n\n\n\n<li><strong>Expansion<\/strong>: Cartridge slot for software, Peripheral Expansion Box (PEB) for memory, disk drives, RS-232, and more<\/li>\n\n\n\n<li><strong>I\/O Ports<\/strong>: Cassette interface, video output (RF modulator), joystick ports (2), cartridge slot<\/li>\n\n\n\n<li><strong>Weight<\/strong>: 2.15 kg (4.74 lbs)<\/li>\n<\/ul>\n\n\n\n<p>&nbsp;<\/p>\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>Operating System<\/strong>:\n<ul class=\"wp-block-list\">\n<li>The TI-99\/4A ran a built-in, ROM-based console operating system that managed hardware resources and provided the user interface.<\/li>\n\n\n\n<li>Its primary user environment was TI BASIC, an ANSI-compliant BASIC interpreter integrated into the system ROM, which acted as both the default operating system shell and programming interface.<\/li>\n\n\n\n<li>Alternative operating systems included UCSD p-System (via a peripheral card), which provided a Pascal-oriented environment, and various third-party disk operating systems for advanced users<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Programming Languages<\/strong>:\n<ul class=\"wp-block-list\">\n<li>TI BASIC (built-in): The default language, based on Dartmouth BASIC, for general programming and learning.<\/li>\n\n\n\n<li>TI Extended BASIC: An enhanced cartridge-based version offering more commands, structured programming features, and improved graphics and sound support.<\/li>\n\n\n\n<li>Assembly Language: Programmable via the Editor\/Assembler cartridge and expansion memory, allowing direct access to the TMS9900 CPU.<\/li>\n\n\n\n<li>GPL (Graphics Programming Language): An internal bytecode language used for system routines and some cartridges.<\/li>\n\n\n\n<li>LOGO: Available via cartridge for educational and graphical programming.<\/li>\n\n\n\n<li>Forth: Supported through third-party cartridges for more advanced, stack-based programming.<\/li>\n\n\n\n<li>Pascal: UCSD Pascal was available with the UCSD p-System card, providing a structured, high-level language environment.<\/li>\n\n\n\n<li>FORTRAN: Supported via third-party software for scientific and engineering applications.<\/li>\n\n\n\n<li>Other Languages: Additional options included My Little Compiler (MLC), TML (The Missing Link), and various third-party BASIC dialects and compilers<figure><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-scaled.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignright size-medium wp-image-21995\" src=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-240x180.jpg\" alt=\"Texas Instruments TI-99\" width=\"240\" height=\"180\" srcset=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-240x180.jpg 240w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-160x120.jpg 160w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-768x577.jpg 768w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-400x300.jpg 400w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-1536x1153.jpg 1536w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-2048x1538.jpg 2048w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-800x600.jpg 800w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/PXL_20250811_183210695-360x270.jpg 360w\" sizes=\"auto, (max-width: 240px) 100vw, 240px\" \/><\/a><\/figure><\/li>\n<\/ul>\n<\/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>First 16-Bit Home Computer: The TI-99\/4A was the world\u2019s first 16-bit home computer, using the TMS9900 CPU originally designed for minicomputers.<\/li>\n\n\n\n<li>Speech Synthesis Pioneer: It was among the first home computers to offer a speech synthesizer peripheral, enabling games and educational software to &#8220;talk&#8221; to users.<\/li>\n\n\n\n<li>Daisy-Chained Expansion: Peripherals connected in a daisy-chain from the side, resulting in a famously long, unwieldy row of add-ons when fully expanded.<\/li>\n\n\n\n<li>Solid State Software: TI branded its ROM cartridges as \u201cSolid State Software,\u201d a term unique to their marketing.<\/li>\n\n\n\n<li>Market Price War: The TI-99\/4A was central to a fierce price war with Commodore, leading to dramatic price drops from $525 to under $100, and ultimately selling at a loss.<\/li>\n\n\n\n<li>\u201cPlug and Play\u201d Hardware: The system featured early plug-and-play capabilities with its cartridge and peripheral support.<\/li>\n\n\n\n<li>Limited Third-Party Software: TI tightly controlled software development, resulting in a limited library compared to competitors<\/li>\n<\/ul>\n\n\n\n<p><strong>Donated By<\/strong>: Arlen Michaels<\/p>\n\n\n\n<p>&nbsp;<\/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>Texas Instruments TI-99\/4A [Vin73] The Texas Instruments TI-99\/4A, launched in 1981, was the world\u2019s first 16-bit home computer, notable for its advanced TMS9900 processor, color graphics, and pioneering speech synthesis peripheral. Its claim to fame lies in introducing 16-bit technology to the home market, influencing later computer architectures and setting a new standard for multimedia [&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-21576","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\/21576","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=21576"}],"version-history":[{"count":3,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/21576\/revisions"}],"predecessor-version":[{"id":25140,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/21576\/revisions\/25140"}],"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=21576"}],"wp:term":[{"taxonomy":"cu_page_type","embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/cu_page_type?post=21576"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}