2008-09-18

Mini85 first CP/M boot

It's alive! There is still a small bug, but I think I've found it already... The Warm Boot sequence (after a CTRL-C) fails. I'm probably not moving correctly the sectors from the disk buffer to the correct place in memory, since the cold boot routine (just after reset) is woring ok.
Next I need to clear this bug and try some CP/M software that runs in 24k since my system needs 8k for the operating system. Since I am using a "standard" CP/M format of a not-so-old CP/M system (P112), and this format is supported by CP/M 3 running in simulator SIMH (the version emulating the Altair), I can create disks and transfer files from the simulator to the real Mini85.
Update: I managed to write a Floppy with a copy of CP/M 2.2 startup disk used in SIMH, corrected the warm boot code, and I filmed the boot sequence with some daylight.
Here's the new video...

video

3 comments:

Alex said...

Cool!!

sounds like an old typewriter! are you sure you didn't build a mechanical computer?

João Silva said...

No this is not the Analytical engine... I try to play Zork on it...

Alex said...

Worm was playable!! and loads of fun! I made more than 200 points!
With the added functionality that each time you lost the floppy would start making noise, making me jump with the scare!