NEC announced the NEAC M4 minicomputer in July 1969. This machine was an ultra-small computer developed for adaptability to a variety of application areas, low price, high performance, and ease of use. It covered a wide range of applications, such as data gathering, process control, data communication, broadcast automation equipment, traffic control, medical equipment and numerical control. Features included: 2 sets of operational registers (each set comprised of a 32-bit accumulator, 16-bit index register, and 16-bit program counter), variable word length, direct address designation up to 4,096 words (8 bits/word) and a 4-level interrupt system with priority.

NEAC M4 Minicomputer