In January 1976, MOS Technologies presented a demonstration computer for their recently developed 6502 processor. MOS, which was acquired by Commodore later that year, needed to show the public what their low-cost processor was able to. The KIM-1 single board computer came fully assembled with an input keypad, a six-digit LED display, and complete documentation. It was intended for developers, but it turned out that at a price of only $249 the computer was the ideal playground for hobbyists, who could now afford a complete computer.
The unforgettable Jim Butterfield described it like this back in 1999:
But suddenly there was the KIM-1. It was fully assembled (although you had to add a power supply). Everybody’s KIM-1 was essentially the same (although the CPU added an extra instruction during the KIM-1’s production life).
And this created something that was never before part of the home computer phenomenon: users could quite happily exchange programs with each other; magazines could publish such programs; and people could talk about a known system.
We knew the 6502 chip was great, but it took quite a while to convince the majority of computer hobbyists. MOS Technology offered this CPU at a price that was a fraction of what the other available chips cost. We faced the attitude that “it must be no good because it’s too cheap,” even though the 6502, with its pipelined architecture, outperformed the 8080 and the 6800.”
↫ Jim Butterfield
Even though there would soon be better equipped and faster home computers (mostly based on the 6502) and the KIM-1 vanished from the collective minds, the home computer revolution started 50 years ago in Jan 1976. Hans Otten keeps the memory alive on his homepage, where you can find a full collection of information about single-board computers and especially the KIM-1.
Dave Plummer, at Dave’s Garage, has done some work on the KIM. I highly recommend the videos.