RCA's CDP1802 "COSMAC", first mooted in 1973 and launched commercially in 1976, was not only the first CMOS processor but was probably the first processor specifically designed for home computers.

It was also unusual in having a radiation-hardened variant, which was useful when it came to be used on NASA's Galileo mission.

Had RCA decided to do something with its chip, it could have been the processor which launched the home computer market. Instead, MOS Technology's 6502 and Zilog's Z80 ended up ruling that particular industry.