Description

The MultiTech MPF-I(B) line of single board computers never had a serial port extension, so this is not a remake. To fill the remainder of the eurocard sized board, a configurable RAM extension is added. Per 4 kByte segment the RAM can be disabled, read-write, read-only or write only (useful to copy a ROM in place). With a non-violent RAM replacement, it is even usable as ROM!

The monitor ROM for the serial port is at the moment quite simple, but intended as an extension to the original MPF_I monitor. It still has 2 kByte room for extension!

More info at my site and github:

https://github.com/electrickery/Z80SerialMonitor (firmware and KiCAD files)

https://www.electrickery.nl/comp/mpf1/Serial_MEM/ (more info and images)

Details

Added a checksum generator to the monitor. This brings the code size just over 2 kByte.

ZMC80 Computer                  2015 MCook
 adaptation to MPF-1 / Z80 DART 2022 F.J.Kraan
Monitor v1.0, ROM: 2000h, RAM: 1800h, DART: 60h

         Input ? for command list
>?
ZMC80 Monitor Command List
? - view command list
C - clear screen
D - print 100h bytes from specified location
E - edit bytes in memory
F - fill memory range with value
G - jump to memory value
K - call to memory value
M - copy bytes in memory
O - write byte to output port
P - print port scan (00-FF)
Q - test MPF keyboard
R - monitor reset
S - calculate checksum for memory range
T - test memory range
Z - dump user registers (STEP)
+ - print next block of memory
- - print previous block of memory

The original ZMC80 monitor can be found here: https://github.com/MatthewWCook/Z80Project/tree/master/Z80%20Monitor%20Part%201/Code

Project Logs

Software & hardware changes

(10/12/2024 at 13:17)

Some of the recent changes:

* The monitor now can use either the DART Channel A or B, depending on a single I/O-port address,

* A four pass RAM test is introduced, which executes seven checks on each address. This will catch most RAM chip and adressing errors,

* For the MPF-I, most keys on the keyboard can be tested,

* On the hardware front, a new version of the board is on its way, using

a 16x BAUD rate clock. This should improve the (still planned) Hex-Intel transfer command.

This project was reposted with the permission of the author. If you are interested in this project and want to know more, Please check the original article: Serial + Memory Card for the Microprofessor MPF-IB | Hackaday.io

And if you want to explore more projects, please follow the author: fjkraan (Hackaday). He has many wonderful projects and is an excellent maker. Enjoy it! :)