μCOM-4 is a microcontroller (microprocessor) family introduced by NEC in 1973. It had a 4-bit architecture. The microcontroller ran at 1 MHz clock speed and had 4Kb of address space. It was manufactured as Sharp requested them for their products. The first chip in the family was the μPD751, a single-chip microprocessor.
NEC released the μPD707 and μPD708, a two-chip 4-bit CPU, in 1971. They were followed by NEC's first single-chip microprocessor, the μPD700, in April 1972. It was a prototype for the μPD751, released in April 1973, combining the μPD707 and μPD708 into a single microprocessor.
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