The TRS-80 Micro Computer System (TRS-80; later known as the Model I to distinguish it from successors) is a desktop microcomputer launched in 1977 and sold by Tandy Corporation through their Radio Shack stores. The name is an abbreviation of Tandy/Radio Shack, Z-80 microprocessor. It was one of the earliest mass-produced and mass-marketed retail personal computers. By 1979, the TRS-80 had the largest selection of software in the microcomputer market. Until 1982, the TRS-80 was the best-selling PC line, outselling the Apple II series by a factor of 5 according to one analysis.
| Manufacturer | Tandy / Radio Shack | CPU | Zilog Z80 @ 1.774 MHz |
|---|---|---|---|
| Year Introduced | 1977 | RAM | 4K |
| Introductory Price | $400 ($599 with monitor) | Storage | Cassette only |
The introductory model contained a version of built in BASIC dubbed “Level 1”, and was limited to 4K of RAM and cassette tape for storage. The external monitor was optional, with an RF modulator the system could be connected to a regular television set.