View Full Version : Single Chip CP/M Board

October 18th, 2011, 12:50 PM
OK so technically its a emulated z80 machine, I ported z80SIM to a Microchip Pic32
boots CP/M and runs very quick .. also have same board emulating TRS-80 and Space invaders arcade game
this is a pic of the hardware

couple of screen shots

October 19th, 2011, 03:18 PM
Pretty interesting. Could you tell more about it before I go register at the website?

Boot from what?
What IO connectors on the board
Software from kenseglerdesigns?

October 19th, 2011, 04:30 PM
No need to register at the site unless you want to leave a comment ..

Board uses a PIC32MX795F512
80MHZ MIPS core
512k flash
128k ram
pic generates vga mono video 80x36 chars
and uses PS/2 Keyboard

Built on z80pack release 1.17
emulates z80 with 64k of ram
uses up to 4 disk can be floopy size or 4mb HD Images stored on MicoSD Card
the header on the side is unused right now .. would be easy to make it show the bus like the altair 8800
will have the source up on my site when i can ..
more info on z80pack here


October 20th, 2011, 09:39 AM
Thanks! looks to be pretty well thought out.

October 20th, 2011, 10:46 AM
Interesting card.
What speed does the emulated z80 run at? Or actually, what speed does CP/M 2.2 think it is running at?

October 20th, 2011, 11:02 AM
Not sure yet, have not figured out a good way to test the speed.
but compared to my Kaypro IV/83 and Model 4P it runs much faster then both of them.
and a lot of it is from using the SD card no slow floppy access .
just need to add VT100 escape codes to the video part .

October 20th, 2011, 02:04 PM
Looks great. Any chance of a writeup as this looks fun!

October 20th, 2011, 04:06 PM
Here's a great writeup on the hardware: http://geoffg.net/maximite.html

Looks like there's even a possible UNIX port: http://developer.mips.com/2011/08/06/about-retrobsd-a-port-of-bsd-unix-to-a-microchip-pic32-microcontroller/

October 20th, 2011, 04:12 PM
Yep that's about the same hardware
here is a thread on the Unix its working now also http://www.thebackshed.com/forum/forum_posts.asp?TID=3925&KW=UNIX
here is a short video of my trs-80 emulator also
still working on the writeup and getting the source on GIThub


October 20th, 2011, 05:43 PM
Thanks for the links to the writeup. I saw this board a few months ago when they said they were thinking of getting CP/M emulated. Nice to see it working. It is almost as if an emulation of CP/M is the new "Hello World" for a microcontroller!