Search found 131 matches

by Lord Nightmare
Tue Sep 15, 2020 3:53 am
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 589
Views: 244613

Re: Reverse Engineering the CIC

Well, first things first: do we have a pinout for the 3198 CIC? Tentatively looking at one SSS-UNROM board, it looks like all the pins might actually go to the card edge, which would mean there's no soldering needed at all. As far as I'm aware, all the CIC chips are SM590 and have the same pinout. ...
by Lord Nightmare
Tue Sep 15, 2020 3:50 am
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 589
Views: 244613

Re: Reverse Engineering the CIC

Jeroen wrote:
Mon Sep 14, 2020 7:44 am
Is there any info on what mnemonics were used?
The "correct" mnemonics come from the SM590 datasheet. The Mnemonics Segher came up with on his post were an educated guess on his part, as we didn't know the part was an SM590 at the time.

LN
by Lord Nightmare
Thu Sep 12, 2019 5:25 pm
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 589
Views: 244613

Re: Reverse Engineering the CIC

At long last, the trick to entering the ROM dump/debug mode of the SM590 was figured out earlier today by Sean Riddle: http://www.seanriddle.com/sm590/ specifically http://www.seanriddle.com/sm590/sm590dump.txt We now have electronic dumps of: 3193A 6113 non-A (which matched the dump done by nevikst...
by Lord Nightmare
Thu Mar 21, 2019 8:37 am
Forum: NES Music
Topic: New VRC7 patch set
Replies: 28
Views: 36183

Re: New VRC7 patch set

How difficult do you think it would be to adopt Nukey's method for the original YM2413? That chip's patch set has yet to be dumped. It seems like, according to the wiki, that grounding the debug pin on the VRC7 seems to turn some of it's other pins into the bus control lines available on the YM2413...
by Lord Nightmare
Thu Mar 21, 2019 1:30 am
Forum: NES Music
Topic: New VRC7 patch set
Replies: 28
Views: 36183

Re: New VRC7 patch set

Nuke.KYT also dumped the 3 drum patches from the VRC7 (yes, the vrc7 has drums in debug mode, but before you get excited, they don't seem to produce any sound on any of the pins, since it seems like the VRC7 doesn't have an RO pin like the YM2413/OPLL does, but if you try to trigger the drums their ...
by Lord Nightmare
Wed Sep 06, 2017 10:03 am
Forum: NESemdev
Topic: Moero Pro Yakyuu voice
Replies: 73
Views: 87357

Re: Moero Pro Yakyuu voice

Without those extra patched bytes (probably an added routine to write to 5000/5001) plus the call patch to get to that area, I cannot test this in an emulator :( Do you have an .ips file patch which can be applied to the "Moero!! Pro Yakyuu (Black) (J).nes" version of the rom to turn it into this on...
by Lord Nightmare
Sun Sep 03, 2017 11:13 pm
Forum: SNESdev
Topic: upd7725 overflow (attn: byuu)
Replies: 24
Views: 9715

Re: upd7725 overflow (attn: byuu)

The 10 blank upd77P20s I have have windows; if I run out, I can always uv-erase them and try again, I think they're good for 100+ prog/erase cycles at least. What I don't have (and I wish I did) are blank upd77P25D chips with windows; those are significantly rarer. EDIT: There is actually someone se...
by Lord Nightmare
Sun Sep 03, 2017 9:24 pm
Forum: SNESdev
Topic: upd7725 overflow (attn: byuu)
Replies: 24
Views: 9715

Re: upd7725 overflow (attn: byuu)

I'm trying to figure out in what circumstances the " if (!flag.ov1) flag.s1 = flag.s0;" should run. In byuu's code in higan, it runs on OP opcodes, before ov1 is recalculated(which I believe is correct), it is updated on any add/sub/adc/sbb/inc/dec opcode(which I believe is correct), it is left alon...
by Lord Nightmare
Thu Aug 31, 2017 2:28 pm
Forum: SNESdev
Topic: upd7725 overflow (attn: byuu)
Replies: 24
Views: 9715

Re: upd7725 overflow (attn: byuu)

> this is an error in the datasheet. ... as well as in the processor. Quite the hardware design oversight. Ruins using the three chained add/sub operations and then saturating the result if you use the B accumulator. Have to use J(N)SB1 now. Based on Ted's note on that site, I don't believe it affe...
by Lord Nightmare
Thu Aug 31, 2017 10:25 am
Forum: SNESdev
Topic: upd7725 overflow (attn: byuu)
Replies: 24
Views: 9715

Re: upd7725 overflow (attn: byuu)

All of the docs came from https://web.archive.org/web/20170313202156/http://www.fabiomontoro.com.br/modem/chips-e-dsps/nec/ I ended up hand-feeding that entire directory of the site to archive.org manually page by page, because the site is hosted on a toaster or something and will go down hard for a...
by Lord Nightmare
Tue Jul 11, 2017 1:38 pm
Forum: NES Music
Topic: Recording request: NEC µPD7756C and the Mitsubishi M50805
Replies: 39
Views: 30070

Re: Recording request: NEC µPD7756C and the Mitsubishi M5080

The 960 byte rom may require etch/staining, which is outside my realm of expertise :(
However it is likely we have the entire contents of it anyway from the data line traces?

LN
by Lord Nightmare
Fri Jul 07, 2017 2:55 pm
Forum: NES Music
Topic: Recording request: NEC µPD7756C and the Mitsubishi M50805
Replies: 39
Views: 30070

Re: Recording request: NEC µPD7756C and the Mitsubishi M5080

sean, can you take a hi-res image of the smaller, visible rom area? I should be able to get the lpc tables extracted, but I need more zoom.

LN
by Lord Nightmare
Sun Jul 02, 2017 10:45 pm
Forum: NES Music
Topic: Recording request: NEC µPD7756C and the Mitsubishi M50805
Replies: 39
Views: 30070

Re: Recording request: NEC µPD7756C and the Mitsubishi M5080

Wow, this is some seriously impressive work! We know from the datasheet that this is LPC-8, not LPC-10, so that simplifies some things. I'm guessing the frame rules are as such: 5,7,6,6,4,4,4,4,4,3 corresponds to energy, repeat+pitch, k1, k2, k3, k4, k5, k6, k7, k8 Technically the real layout is: 5,...
by Lord Nightmare
Sun Jun 25, 2017 11:00 pm
Forum: NES Music
Topic: Recording request: NEC µPD7756C and the Mitsubishi M50805
Replies: 39
Views: 30070

Re: Recording request: NEC µPD7756C and the Mitsubishi M5080

lidnariq wrote:That math looks off?
aerobics0-conversion-error-maybe.png
Shouldn't the waveform follow roughly where I've added it in red, rather than the weird flip?

This doesn't look quite right, I'll need to ask Sean about it later. Probably a sign got flipped somewhere...

LN
by Lord Nightmare
Sat Jun 24, 2017 7:37 pm
Forum: NES Music
Topic: Recording request: NEC µPD7756C and the Mitsubishi M50805
Replies: 39
Views: 30070

Re: Recording request: NEC µPD7756C and the Mitsubishi M5080

The fun bit is gonna be unboiling the egg and turning the recovered 12?-bit pcm data back into the 4-bit-per-sample source adpcm data from the 7756c mask rom. That's actually possibly doable, since theres only 16 possibilities per sample and you can do analysis-by-synthesis to find best fit for each...