Nibbler 4 Bit CPU

Nibbler is a 4 bit CPU built from standard 7400 series logic chips individual counters, registers, buffers, and gates. Its an educational example of a simple CPU thats easy to understand and build, but still capable of running games and other interesting programs. Nibbler is built using wire-wrapping on a 5 x 4 inch (127 x 102 mm) perfboard. The CPU contains 17 chips in total.”