![\"Morrow](\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/PXL_20250716_185727888-scaled.jpg\")
<\/a><\/p>\n- \n
- Manufacturer<\/strong>: Morrow Designs, Inc.<\/li>\n
- Type<\/strong>: Desktop<\/li>\n
- Release Date<\/strong>: 1982<\/li>\n
- Cost at release<\/strong>: USD $1,790 (CAD ~$6,500 adjusted for inflation)<\/li>\n
- MIPS<\/strong>: 0.58 (580KIPS)<\/li>\n<\/ul>\n
Hardware Specifications<\/h3>\n
- \n
- CPU<\/strong>: Z80A running at 4 MHz<\/li>\n
- Memory<\/strong>: 64 KB dynamic RAM<\/li>\n
- Storage<\/strong>: Two 5.25-inch double-sided, double-density floppy drives (400 KB total storage)<\/li>\n
- Single-board computer design (no S-100 bus)<\/li>\n
- Two RS-232C serial ports (for terminal and printer\/modem)<\/li>\n
- One parallel port (for printer)<\/li>\n
- Convection-cooled, fanless operation (very quiet)<\/li>\n
- RF-shielded metal case<\/li>\n
- Dimensions<\/strong>: ~16.7″ wide x 11.3″ deep x 5.3″ high<\/li>\n
- Weight<\/strong>: ~6 kg<\/li>\n<\/ul>\n
Operating System & Programming Languages<\/h3>\n
- \n
- OS<\/strong>: CP\/M 2.2 operating system, enhanced with a user-friendly menu system called Micro Menu.<\/li>\n
- Programming Languages<\/strong>: Microsoft BASIC-80, Morrow\u2019s own BaZic, PILOT, and other CP\/M-compatible languages such as FORTRAN, COBOL, and assembly language.<\/li>\n<\/ul>\n
Notables<\/h3>\n
- \n
- George Morrow was a key innovator in early personal computing, best known for his work in standardizing the S-100 bus (IEEE-696), which enabled broad hardware compatibility and expansion in microcomputers. He founded Morrow Designs and introduced affordable, reliable memory boards, S-100 floppy disk controllers, and complete systems that bundled CP\/M, BASIC, and business software. Notably, Morrow Designs offered branded 8-inch floppy drives and hard disk systems, making high-capacity storage accessible to small businesses and hobbyists at a reasonable price.<\/li>\n
- The Morrow Micro Decision MD-3 was one of the last popular CP\/M business computers before the IBM PC era, known for its quiet, fanless operation and compact, all-in-one design.<\/li>\n
- The MD-3 was praised for its reliability and expandability, with users often modifying systems to add more drives or RAM.<\/li>\n
- The MD-3 was featured in creative advertisements highlighting its quietness and value, and it was used in small businesses, schools, and even early BBS systems.<\/li>\n
- Its place in history is as a transitional machine\u2014bridging the gap between hobbyist S-100 systems and the dominance of IBM PC compatibles, and representing the end of the CP\/M era in business computing.<\/li>\n<\/ul>\n
Donated by<\/strong>: Dr. Arlen Michaels<\/p>\n","protected":false},"excerpt":{"rendered":"
Morrow Designs Micro Decision MD-3 [Vin134] The Morrow Designs Micro Decision MD-3, released in the early 1980s, was a Z80A-based CP\/M microcomputer designed to offer affordable, quiet, and user-friendly desktop computing. The MD-3 distinguished itself with two double-sided, half-height 5.25-inch floppy drives, providing a total storage capacity of 400 KB\u2014an upgrade over earlier MD models. […]<\/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":"\n
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- Programming Languages<\/strong>: Microsoft BASIC-80, Morrow\u2019s own BaZic, PILOT, and other CP\/M-compatible languages such as FORTRAN, COBOL, and assembly language.<\/li>\n<\/ul>\n
- Memory<\/strong>: 64 KB dynamic RAM<\/li>\n
- Type<\/strong>: Desktop<\/li>\n