{"id":22517,"date":"2025-10-30T11:44:23","date_gmt":"2025-10-30T15:44:23","guid":{"rendered":"https:\/\/carleton.ca\/scs\/?page_id=22517"},"modified":"2025-10-30T12:02:46","modified_gmt":"2025-10-30T16:02:46","slug":"vin120","status":"publish","type":"page","link":"https:\/\/carleton.ca\/scs\/vintage-computing\/item\/vin120\/","title":{"rendered":"Tandy TRS-80 Model 4p"},"content":{"rendered":"<h2>Tandy TRS-80 Model 4p<\/h2>\n<p>[Vin120]<\/p>\n<p>The TRS-80 Model 4P was one of the earliest truly portable microcomputers offering full desktop capabilities with dual built-in floppy drives, integrated screen, and keyboard in a single transportable unit weighing about 26 pounds. It bridged the gap between desktop and portable computing, maintaining backward compatibility with the popular TRS-80 Model III and access to numerous CP\/M applications, effectively enabling professional mobile computing for the first time. It was praised for its combination of power and portability, marketed as &#8220;full desktop power, anywhere,&#8221; though its weight made it relatively a &#8220;luggable&#8221; rather than a lightweight portable by modern standards. Despite being well-engineered and favored by traveling professionals, it saw limited commercial success. Its place in history marks an important step in the evolution from home\/desktop microcomputers toward compact laptops.<a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-scaled.jpg\"><img decoding=\"async\" loading=\"lazy\" class=\"alignright size-large wp-image-22239\" src=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-400x300.jpg\" alt=\"Tandy TRS-80 Model 4P\" width=\"400\" height=\"300\" srcset=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-400x300.jpg 400w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-240x180.jpg 240w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-160x120.jpg 160w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-768x577.jpg 768w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-1536x1153.jpg 1536w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-2048x1538.jpg 2048w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-800x600.jpg 800w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250923_175428570-360x270.jpg 360w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><\/a><\/p>\n<ul>\n<li><strong>Manufacturer<\/strong>: Tandy Corporation (Radio Shack)<\/li>\n<li><strong>Type<\/strong>: Luggable Computer<\/li>\n<li><strong>Release Date<\/strong>: 1983<\/li>\n<li><strong>Cost at release<\/strong>: $1,799 (CAD ~$6,200 adjusted for inflation)<\/li>\n<li><strong>MIPS<\/strong>: 0.5 (500 KIPS)<\/li>\n<\/ul>\n<h3><span class=\"TextRun SCXW36078203 BCX0\" lang=\"EN-US\" xml:lang=\"EN-US\" data-contrast=\"auto\"><span class=\"NormalTextRun SCXW36078203 BCX0\">Hardware Specifications<\/span><\/span><\/h3>\n<ul>\n<li><strong>CPU<\/strong>: Zilog Z80A running at 4 MHz, with some upgrades supporting 6.144 MHz (Hitachi HD64180\/Z180).\u200b<\/li>\n<li><strong>Memory<\/strong>: 64 KB of RAM, expandable to 128 KB, with some modifications supporting up to 384 KB using additional memory boards.\u200b<\/li>\n<li><strong>Video Display<\/strong>: 9-inch green monochrome CRT monitor with an 80&#215;24 character text display.\u200b<\/li>\n<li><strong>Storage<\/strong>: Dual built-in 5.25-inch floppy disk drives (184 KB each), with some external mods for additional drives.\u200b<\/li>\n<li><strong>Weight<\/strong>: Approximately 26 pounds (11.8 kg).\u200b<\/li>\n<li><strong>Additional features<\/strong>: Built-in speaker for simple sound; compatibility with TRSDOS and CP\/M; external connector options for peripherals, including modem and serial ports.<\/li>\n<\/ul>\n<h3><span class=\"TextRun SCXW136206418 BCX0\" lang=\"EN-US\" xml:lang=\"EN-US\" data-contrast=\"auto\"><span class=\"NormalTextRun SCXW136206418 BCX0\">Operating System &amp; Programming Languages<\/span><\/span><span class=\"EOP SCXW136206418 BCX0\" data-ccp-props=\"{&quot;335559685&quot;:0}\">\u00a0<\/span><\/h3>\n<ul>\n<li class=\"my-0\"><strong>Operating System<\/strong>: TRSDOS 6, an enhanced version of the TRS-80 Disk Operating System developed by Logical Systems and compatible with LDOS 6.00. It also supported CP\/M (Control Program for Microcomputers)<\/li>\n<li><strong>Supported Languages<\/strong>: Microsoft 5.0 BASIC (included with the system), Zilog Z80 Assembly language, and via CP\/M: Pascal, COBOL and Fortran<\/li>\n<\/ul>\n<h3>Notables<\/h3>\n<ul>\n<li>The Model 4P was the first portable TRS-80 with built-in dual 5.25-inch floppy drives and a full 80\u00d724 character display, distinguishing it from earlier limited-display portables.\u200b<\/li>\n<li>Despite being described as a &#8220;smashing success&#8221; by InfoWorld in 1983 for its &#8220;carefully thought-out mechanical design&#8221; and &#8220;outstanding product at an excellent price,&#8221; it was commercially unsuccessful and discontinued by early 1985.\u200b<\/li>\n<li>Tandy acknowledged that &#8220;transportables just weren&#8217;t moving well for any company that also sold a desktop version&#8221; when explaining the discontinuation<\/li>\n<li>Represented one of the earliest attempts at\u00a0<strong>&#8220;full desktop power, anywhere&#8221;<\/strong>\u00a0computing, bridging desktop and portable computing eras.<\/li>\n<\/ul>\n<p><strong>Donated by<\/strong>: Dr Arlen Michaels<\/p>\n<p><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD.jpg\"><img decoding=\"async\" loading=\"lazy\" class=\"alignleft size-full wp-image-22521\" src=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD.jpg\" alt=\"\" width=\"810\" height=\"1080\" srcset=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD.jpg 810w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD-240x320.jpg 240w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD-400x533.jpg 400w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD-160x213.jpg 160w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD-768x1024.jpg 768w, https:\/\/carleton.ca\/scs\/wp-content\/uploads\/Tandy_TRS-80Model4p-AD-360x480.jpg 360w\" sizes=\"(max-width: 810px) 100vw, 810px\" \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tandy TRS-80 Model 4p [Vin120] The TRS-80 Model 4P was one of the earliest truly portable microcomputers offering full desktop capabilities with dual built-in floppy drives, integrated screen, and keyboard in a single transportable unit weighing about 26 pounds. It bridged the gap between desktop and portable computing, maintaining backward compatibility with the popular TRS-80 [&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>Tandy TRS-80 Model 4p - 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