1980 TRS-80 model III

The model 3 is generally regarded as the successor to the Model 1. Its two 5.25″ floppy disk drives could convert model 1 disks.

Initially Radio Shack wanted to sell both the model 1 and 3 at the same time, but the FCC forced them to stop selling model 1. Is so they were discontinued because of the excessive radio noise that they put out.

However, the Model 3 wasn’t FULLY compatible with the model 1. There were differences in ROM which meant some programs had to be converted, especially those machine language ones that made ROM calls.

NAME   TRS 80 MODEL III
MANUFACTURER   Tandy Radio Shack
TYPE   Home Computer
ORIGIN   U.S.A.
YEAR   1981
END OF PRODUCTION   Unknown
BUILT IN LANGUAGE   TRS-80 Level II BASIC
KEYBOARD   Full-stroke keyboard with separated numeric keypad
CPU   Zilog Z80 then Z80A
SPEED   2.03 MHz
RAM   16 KB (up to 48 KB)
ROM   14 KB
TEXT MODES   32 or 64 columns x 16 lines
GRAPHIC MODES   128 graphic characters
COLORS   monochrome
I/O PORTS   Tape (500 or 1500 bauds), Centronics, RS232
BUILT IN MEDIA   Zero, one or two 5.25” disk-drives.
OS   TRS DOS (other OSes were available : New DOS, LDOS, MultiDOS, …)
POWER SUPPLY   Built-in power supply unit
PERIPHERALS   Various Tandy peripherals
PRICE   No disk model : AU$1450 (Australia, 1981)
$2495 in 1984 for a complete system with 2×360 KB drives, TRSDOS, 64kb Ram, software and printer

Filed under: 80s Computers - @ January 31, 2022 11:54 AM