Legendary Tech
Filter
//
✓ VERIFIED

TRS-80 Model I

26-1002 · 1977–1981 · desktop

Specifications

Cpu
Zilog Z80, 1.77 MHz
Ram
max: 48 KB with a Tandy Expansion Interface · base: 4 KB
Ports
Cassette in/out · Expansion Interface bus connector · Built-in monitor (integrated, not a separate port)
Display
Built-in monochrome monitor, 64×16 text (32×16 in wide mode), block graphics
Storage
base: Cassette tape via a standard cassette recorder (no internal storage) · options: 5.25" floppy disk drive(s) via the Expansion Interface
Os Support
latest: TRSDOS with Level II (Microsoft) BASIC · shipped: Level I BASIC in ROM
Release Price
$599.95 (with monitor and cassette recorder)

Upgrade paths

RAM
48 KB via the Tandy Expansion Interface · The Expansion Interface is a separate box that sits under the keyboard unit, adding RAM up to 48 KB, a floppy controller, and a real parallel printer port.
MODERATE
storage
Up to 4 external 5.25" floppy drives via the Expansion Interface's disk controller · Turned a cassette-only machine into a disk-based system, the configuration most Model I software libraries assumed.
MODERATE