SSL Computer ROMs (Recreating the Computer)

[mike_signo]

Hi guys, hope you’re all well.

I’ve been reverse engineering the SSL computer, and I found that besides the floppy, you also need a lot of data stored in the ROM inside the computer. I have a working unit, but I don’t have an EEPROM reader. Does anyone have EEPROM bin files saved that they’d be willing to share? It would help a lot.

On the plus side, I’ve got the computer running in a virtual machine. There’s still plenty of work to do, mainly because Total Recall is a separate computer and I can’t get it working yet, but I’m confident we’ll get there.

Thanks,
Michele

[pascal.verdet]

Hi Michele,

Great! We are also working on the same project with a colleague named Steve.
If we could exchange information, that would be a significant step forward.

A quick clarification: Most of the ROMs in the computer are those found on the NM4 boards and in the character generator for the VDU board...
The same applies to the "Total Recall" section...
One exception is the Ultimation interface board, which is built around an 8032 processor, with its program stored in ROM.

For my part, I have attempted to develop something similar using an Arduino's architecture, CAN Bus and a touchscreen.
I also thought that a "scribble strip display" would be a nice addition to the channel multiplexer board. (see the attached photos).

If we could pool our resources, that would be a very good thing. I am particularly curious about your "virtual machine."

With my best.
Pascal

[mike_signo]

Hi Pascal,

Thanks a lot for the EPROM dumps, that’s really appreciated.
I'm happy to see that you're working on it as well. Your Arduino, CAN bus and touchscreen version looks amazing too. Nice to see that it's already interfacing with hardware.

It would be useful to stay in touch and compare notes on common issues as we go. I’ll be honest that, from past experience, collaborating on projects like this can be difficult, so I’m a bit careful about it. But I’m happy to share as much info as I can.

Best wishes to you and Steve.

Michele

[mike_signo]

Thanks again Pascal, they have been very useful.
One of them looks like a bad read though: 683TR22F, the Total Recall EPROM (TMS2716, "Total Recall EPROM v 2.0f"). The file is 2 KB, but only the first 512 bytes and the last 512 bytes contain data. The whole middle 1 KB is FF. The code that is there calls routines that aren't in the file, and the Total Recall program on the SSL program disk also calls routines in the F600 to F7FF range that read as blank in this dump.
My guess is the read missed part of the chip, which would fit how awkward the TMS2716 is to read. It needs +12 V and -5 V, and A10 is on a different pin from a normal 2716.
The rest are fine and run in my emulator: P2970270 (VDU character ROM), P3010431 and P3010421 (RML COS 3.4), P3560404 (Ultimation 8051 firmware), plus the PROMs and JED files.
Does anyone have another read of 683TR22F,