68k-MBC Builds a CP/M-68K Computer Around Just Three Main Chips

The 2026 Retrocomputing Challenge produces the 68k-MBC, an all-through-hole homebrew computer running CP/M-68K powered by a Motorola 68008 and three chips.

The 2026 Retrocomputing Challenge has produced a wonderfully minimalist machine in the 68k-MBC, an all-through-hole homebrew computer built around Motorola's 68008 processor. Its particularly entertaining Lite configuration uses only three principal ICs: the 68008 CPU, an SRAM device and a PIC microcontroller acting as ROM and system glue. That is a remarkably small silicon committee for a computer capable of running CP/M-68K and standalone 68K executables.

The Lite machine supports up to 512KB of RAM and a serial interface, while I2C expansion allows builders to add extras such as an SD-card 'hard drive' or real-time clock. Serial connectivity means a conventional terminal can become the display and keyboard, and suitably determined owners can even connect a thermal printer. A fuller configuration expands connectivity with a second serial port, while a parallel adapter accommodates older printers.

The project is particularly charming because it represents retrocomputing in the active sense rather than simply preserving an old commercial machine. Nobody manufactured this computer in 1983; instead, modern hobbyists are applying period-appropriate ideas and processors to create alternate-history hardware today. The 68008 once helped power machines such as the Sinclair QL. In 2026 it is discovering that three chips, half a megabyte and CP/M are apparently enough to start a completely new career.