I saw a few other MCB-1 posts here on the forum - just wondering if these users are still active and managed to get their systems running?

I acquired my MCB-1 about 5 years ago and never got to do anything with it because of the lack of good documentation. Recently, I did a deep dive into the ROM and manuals that I have for the system and was able to bootstrap myself a bit - at least I can now control the display, and read from the keyboard. In the manual I have for the MCB-1, the three routines DISP, KEYIN, and DELAY1 are mentioned as being useful monitor routines for your own programs, but neither the addresses of the routines nor the calling conventions were disclosed! It is actually listed as an assingment for the students to go take the commented / annotated ROM listing and figure out the details (start addresses and calling conventions). Unfortunately, I don't own the annotated / commented ROM listing.

However, I was able to identify these routines by comparing a ROM dump to an annotated / commented ROM listing from the successor model, the MCB-1A, which was much improved (16 KBs of RAM instead of 4 KBs, alphanumeric display instead of 8x 7segment digits, etc.)

I made a little demo video here:

If there are other users here that have the annotated / commented MCB-1 ROM listing, or wrote programs and know more details about the OS and its routines, I'd like to hear from them.

There is little to no information about this system on the internet. Maybe together we can put out some content that allows folks to use their MCB-1's for something.

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