Originally Posted by seanriddle
Originally Posted by Rik
Found a Rockwell B9001-13 in Mattel's Horoscope Computer. Where any of the earlier Mattel LED games (like Battlestar Galactica) dumpable, or was decapping used for that?
Interesting; B9000-12 is in Mattel's Brain Baffler.

I've decapped several of the Rockwell chips from Mattel games, but haven't figured out how to emulate them yet. It's definitely high on my list.
Looks like we may be partially in luck on Horoscope and Brain Baffler. When I was putting together info on the PPS-4/1 variants, I ran across part # B90xx in the 1981 Rockwell Electronic Devices Division Data Book, which says that's model MM78LA. There's very little info beyond an entry in a comparison chart, but that leads me to believe that it uses the same opcodes as the MM78. It has the same ROM and RAM sizes (2K ROM, 128 nibbles RAM), but has a few new features- speaker output, including an 8-bit tone generator counter, and 14 segment outputs, using a 32x14 PLA. (Brain Baffler has an 8-character 14-segment text display.) MM78s have a test pin, so it's possible that MM78LAs do, too. But I've been unable to find any more info anywhere.

The other PPS-4/1 chips have part #s ranging from A75xx to B86xx, and the chips in Mattel games Battlestar Galactica, Football and Baseball are labeled B60xx and B61xx. I think that indicates that these chips aren't quite PPS-4/1; I have some Rockwell calculators with chips labeled A48xx, B50xx and A59xx. If we're lucky, the chips in the Mattel games share enough characteristics with the PPS-4/1 that we can get them emulated.

I've decapped Battlestar Galactica, Football and Baseball. BSG has 512 bytes of ROM, and Football and Baseball have 896 (the PPS-4/1 chips don't always have power-of-2 pages of 64 bytes).

After Kevin dumps the MM75 and MM76EL chips that I sent him, I'll decap them and see how similar they look to the Mattel chips. If they are close, then I should be able to figure out the bit mapping between his dumps and the ROM array pics, and I can apply those to the Mattel ROM array pics and see what I get. If we're really lucky, the opcodes will be the same as PPS-4/1.