Search found 176 matches

by Fiskbit
Thu Sep 24, 2020 12:53 am
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

I believe CIC pins 1 and 2 are the ones that should be outputting your missing bits.
by Fiskbit
Wed Sep 23, 2020 7:09 pm
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

I haven't seen anything yet that would make me think these are SM591 or SM595 chips. Even if they were, we should be getting the first field, and would know it's incomplete because the code in that field would have jump instructions referencing the other field.
by Fiskbit
Wed Sep 23, 2020 4:17 pm
Forum: NESemdev
Topic: Photo-Sensitive Epilepsy Safe NES/SNES Emulation?
Replies: 4
Views: 151

Re: Photo-Sensitive Epilepsy Safe NES/SNES Emulation?

Mesen has Lua scripting ( see documentation ). It can write to palette RAM. It can also read/write the color of a given pixel or even the whole screenbuffer, apparently with 32-bit ARGB color. I think this is good enough to do what I've suggested, though it could get confused if there are two identi...
by Fiskbit
Wed Sep 23, 2020 4:06 pm
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

Do you get that starting point without my changes but with the extra 256 clocks before ACL drops? That dump is starting at page 3, which is really weird. I wonder if the 256 instruction clocks before ACL drops are advancing the instruction pointer to get from page 1 (standby behavior) to page 3, but...
by Fiskbit
Wed Sep 23, 2020 2:52 pm
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

Good find on the need for 2 instruction cycles for reset after power-on. I'll be curious to see if this resolves the problems we're seeing, though I'm not convinced it will remove the 1 instruction jitter. Note that our moving the sampling position was intended to keep it in the same part of the ins...
by Fiskbit
Wed Sep 23, 2020 1:29 pm
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

I don't have the code on-hand at the moment, but the two changes I remember that aren't reflected in Jeroen's latest update are a single added ClockMacro() before lowering ACL: ClockMacro(); PORTC &= 0b11101111;// lower ACL and moving where dataArray is sampled, to compensate for the above change: f...
by Fiskbit
Wed Sep 23, 2020 1:21 pm
Forum: NESemdev
Topic: Photo-Sensitive Epilepsy Safe NES/SNES Emulation?
Replies: 4
Views: 151

Re: Photo-Sensitive Epilepsy Safe NES/SNES Emulation?

(Sorry, didn't see this thread before responding in the Mesen one. Here's what I posted there:) I think you could automatically detect this with something along the lines of looking for large changes in a color histogram across adjacent frames, and doing some kind of effect when this is detected too...
by Fiskbit
Wed Sep 23, 2020 1:19 pm
Forum: NESemdev
Topic: Mesen - NES Emulator
Replies: 866
Views: 394491

Re: Mesen - NES Emulator

Sour is on indefinite break right now, but regarding the flashing, I think you could automatically detect this with something along the lines of looking for large changes in a color histogram across adjacent frames, and doing some kind of effect when this is detected too many times in a short window...
by Fiskbit
Wed Sep 23, 2020 3:10 am
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

Worked on this some tonight with a friend. We were able to dump a 3193A and confirm that it matches the accessible 508 bytes of the existing 512 byte dump. We also tried to dump a 6113B1, but were unsuccessful. We used Jeroen's code with an Arduino Diecimila. If you're using an Arduino like this wit...
by Fiskbit
Tue Sep 22, 2020 4:21 pm
Forum: NESemdev
Topic: Mesen - NES Emulator
Replies: 866
Views: 394491

Re: Mesen - NES Emulator

Different serial registers have different ways of handling the serial writes. w is used specifically for the $2005 and $2006 PPU writes, which take 2 writes. You're correct that interrupts can be a big problem for serial registers; if the handler needs to use a serial register that is also used outs...
by Fiskbit
Tue Sep 22, 2020 3:55 pm
Forum: NESemdev
Topic: Mesen - NES Emulator
Replies: 866
Views: 394491

Re: Mesen - NES Emulator

Based on your edit, you mean w in the PPU? That's shown in the debugger as "Write Toggle", and yeah, you can see the state of w in the event viewer on $2005 and $2006 writes.
by Fiskbit
Tue Sep 22, 2020 3:09 pm
Forum: NES Hardware and Flash Equipment
Topic: Twin Famicom - Only discs shows messed up graphics
Replies: 7
Views: 179

Re: Twin Famicom - Only discs shows messed up graphics

Does the issue correct itself after you leave the title screen? NESRGB has some kind of issue where palettes can be wrong shortly after reset. I often see this manifest as bad colors on the Zelda 1 title screen.
by Fiskbit
Tue Sep 22, 2020 1:52 pm
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

To be clear, it's the PRG and CHR ROMs on that cart I'm interested in, not the CIC (though I do think it's worth it to try dumping your other CICs in case it's damage and they didn't all suffer the same fate). I think the FamicomStation menu is currently undumped.
by Fiskbit
Tue Sep 22, 2020 1:22 pm
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

Handling of the slot ID should be a purely software thing. These lines are hooked up to IO pins on the device, which the CIC software can read from to determine the ID. The dump mechanism isn't running the software, just reading it out, so it shouldn't be able to make a difference. Do you have a CIC...
by Fiskbit
Tue Sep 22, 2020 12:11 am
Forum: NES Hardware and Flash Equipment
Topic: Reverse Engineering the CIC
Replies: 549
Views: 227057

Re: Reverse Engineering the CIC

Can you confirm that the cart connector pins 16-19 actually go somewhere on the motherboard for all the slots? I had thought that these lines were hardcoded for a given slot (presumably tied to 5v and ground to produce a fixed ID for each given slot), but maybe I've misunderstood. I probably won't b...