Dumping/reverse engineering MSX models thread | MSX Resource Center (Page 29/30)

Resident (38)

12-03-2023, 19:55

Hello

I've dumped all the ROM ICs from my Victor HC-90(A). I think the they're different from the HC-95, because some key combinations listed in the wiki do not work with my computer. If someone can confirm, it would be great!

Here are some pictures too:
https://drive.google.com/drive/folders/1U1Vc9ex6tGCqYNN6n_N2...

By Manuel

Ascended (19467)

12-03-2023, 21:08

What is going on above IC02??

Anyway, I'll check the dumps.

So, it's the 1-drive model, right?

It might be me, but I don't see the videochip... which VDP does it have?

By dproldan

Resident (38)

12-03-2023, 21:17

Those wires are connecting the CS and OE pins of IC023 (main ROM) to some glue logic. I have to check why it's rewired.
Yes, only one drive. I'll upload more pictures tomorrow.

The VDP (9938) is located in another PCB, this computer has the "analog" and the digital parts completely separated. I'll take a picture of that too.

By Manuel

Ascended (19467)

12-03-2023, 21:58

The ROMs (at least for Z80 mode) seem to be identical to the ones I dumped years ago of a HC-95A, except that this direct dump didn't include some register values just before the middle of IC052 (of course).

Thanks for that VDP info, the thing is that the one I dumped seemed to have a V9958.

Can you also dump the kanji ROM? Dumping from software with the kanji dump tool is fine.

And perhaps also dump the RAM slot, to see the initial content of the RAM.

By dproldan

Resident (38)

17-03-2023, 23:30

re: the Victor HC-90

I've added a couple of pictures of the front and the back of the "analog" PCB, with all the video circuits.
Also dumped and added the "kanji.rom" file.
https://drive.google.com/drive/folders/1U1Vc9ex6tGCqYNN6n_N25PAOjjCvtxMx?usp=sharing

I haven't found how to dump the ram :-(

By Manuel

Ascended (19467)

18-03-2023, 00:15

Dump it as a straight 64k ROM with saverom.com