Texas Instruments TM 990/189

Summary

The TM 990/189 is a Texas Instruments 8-bit microcomputer. Built from 1978 to about 1981, the circuit board computer found its place in the training, was programmed via a calculator keyboard, and half of the calculator is reminiscent of a TI-59 with a red 7-segment LED for output. After switching on the display “CPU reADY” appears and after activating the return key “Ret” you are in the input mode of the built-in machine language editor, which is displayed with ”?”. The serial number of this computer is 24, i.e. one of the first ever produced TM 990/189. Exceptionally on this single-board computer is the aluminum housing, in which the power supply is also accommodated. Extension boards like the TMS 9902 can be connected via the bus.