MP/M 2.1 running on my eZ80

[Dean Netherton]

I have recently been exploring MP/M and porting it to work on my eZ80 for RC module.  Now I have another retro OS for the platform.

I know I am not the first to get MP/M running on an eZ80 and I am very new to MP/M and still learning the way it works.

The initial port boots and run some simple programs.  I still need to do a few more things - the bank switching is far from optimal - and have yet to try with larger more complex programs.

Do liked the way I committed the original DRI code to my repo? - a commit made 45 years ago!

The customised bios (BNKXIOS) I wrote is assembled using the modern gnu assembler (for ez80), with some eZ80's extended instructions used - but the main OS is still using the original intel compatible code.

I wrote about it a bit on my blog: https://www.dinoboards.com.au/2026/07/10/MPM-ported.html

Dean.