Texas Instruments TMS1000 microcontroller family

Texas Instruments TMS1000 family of 4-bit microcontrollers was introduced in 1974. The TMS 1000 microcontrollers had very simple design - only 2 4-bit general registers, 43 instructions (expanded to 54 instructions in TMS1100/TMS1300), 1-level deep stack, shift-register program counter and no interrupts.

The TMS1000/TMS1070 were basic microcontrollers with 1 KB of masked ROM and 64 x 4 bits of RAM. ROM and RAM memory size was doubled on TMS1100 microcontrollers. TMS1200/TMS1270/TMS1300 microcontrollers were similar to TMS1000/TMS1070/TMS1100 respectively, but had more output lines. The TMS1070 and TMS1270 could directly interface to high voltage displays.