TM990 / 189 Microcomputer ( 1979)


tm990The TM990/189 is a self- contained, single board microcomputer system. It is intended for use as a learning aid inlibri instruction of microcomputer fundamentals, machine and assembly language programming, and microcomputer
interfacing. It also demostrates TMS 9900 family applications and advanteges.



- TMS9980a microprocessor
-1024 bytes RAM
- 4096 bytes ROM
- 2 mhz oscillator
- audio cassette interfaces
- 16 biti I/O programmable
- 45 key alphanumeric keyboard
- Ten-digit, sevn-segment led
- Visual and acoustic indicators
- TMS9902 asynchronous communication controllers

 tm 990 189 00In the various events we attended, we were able to put a TM990 / 189 into operation. The main feature is to have a Basic interpreter on board, and to interface it with the Travelmate 560 via the RS232 serial. Programs are read and written via a recorder for the TI-99/4A PHP-2700.

The program loaded via laptop is a small program to generate a clock with hours, minutes and seconds.