Arduino Mega based Z80 CPU board tester

Inspired by discussions at the TRS-80 Dutch Usergroup meetings, I created a board exorciser for Z80 CPU based computers. It allows memory inspection, writing to memory, I/O port reading and writing, and low level signal exercising. In short, a tool which can help troubleshooting Z80 boards.

As it does not use a real Z80, signals are easier to check as the Z80 refresh for dynamic RAM does not interfere. As a result a dynamic RAM test will not work, but all address, data and control lines can be exercised with simple patterns, slowing the process so a logic probe can effectively be used.

The Arduino Mega is the only expensive parts needed, other parts need some soldering experience. But beware, this will not fix your broken computer. It can only help you fixing it!

There are two modes of operation;