SCP S-100 machine - how to start it?

[Torinde]

It seems the ROM files for "s100" are not in the release package and I can't find "MON_1.5_1982-06-10_CROMEMCO4FDC.BIN" - should I get it from MAME?

I want to try some of the available images for QDOS/86-DOS (SCP, NSI) and there are such for SCP Cromemco 4FDC (and SCP Tarbell and North Star).

[dbalsom]

There is no actual S-100 machine or hardware support. The S-100 ROM definition I added was just for an experiment to boot the SCP 8086 ROM monitor code and see what it did.

[dbalsom]

that file wasn't actually supposed to be in the release :P Oops.

[Torinde]

Clear, but then for the reason above - I suggest it as a feature :)

Source code for the controllers (86Box/86Box#3857 (reply in thread)):
https://github.com/simh/simh/blob/master/AltairZ80/s100_tarbell.c
https://github.com/simh/simh/blob/master/AltairZ80/s100_64fdc.c

Related: joncampbell123/dosbox-x#5062 (comment)

[dbalsom]

The SIMH source tree is poisoned by some unfortunate drama surrounding incompatible license changes by the maintainer.
The Open-SIMH project is the continuation of the original open-source effort.
https://github.com/open-simh

That said, I generally do not borrow code from other emulators or projects. I prefer to implement things directly from documentation or hardware research.

[Torinde]

Great, here is some documentation about SCP200B.

• "ROM Monitor", YASM port

[Torinde]

It seems SCP200B supported disabling the boot ROM after boot-up, which allows for DOS to utilize the whole 1MB as Conventional memory: Microsoft were using that for "linking the linker" until 386 came.