- 2023
- Dec
- 3
An MMD1 8080 Trainer
This guy was given to me, well, probably in the late 90s because it was missing it’s 8224 clock chip. The person that gave it to me, since deceased, didn’t really want to go through the trouble of finding one so he asked if I’d like the device instead. Sure, why not.
I eventually found an 8224 on a device at a show, and put it in recently. I then realized that, unlike most other trainers, this one has no LED numeric displays! Well… the HALT LED will light and extinguish if I play with the keyboard, so I assume something is going on since it didn’t do that before. I thought about dumping the monitor ROM, but someone has already done that. I also need to investigate the power supply, it has a very loud hum and may need some modernization.
It’s nothing really special, just another one of many 8080 trainers that were available on the market. It will go beside my FOX Z80 trainer and my BellMAC 8 device for display. After it gets a little cleanup, of course, the thing was filthy when I got it and I have not done a thing with it.
The monitor ROM and some other information is presented here: http://www.decodesystems.com/mmd1.html