Recent content by ack

Some of the jumpers (including JP10) have a small trace between the pads so they are shorted by default and you have to cut the trace to disable.

You can see how your script compares to this. https://www.mvs-scans.com/misc/cps2-crypt.cpp Its code I wrote a while ago when I was looking into encrypting roms for a project I'm working on, but it also supports the full decryption like MAME does. $ g++ cps2-crypt.cpp -o cps2-crypt $...

Is it possible its just wrong because its byte swapped? If you are decrypting the rom file, then writing out the decrypted rom, it will be byte swapped compared to what you see in mame's debugger.

Not sure what your end goal is but the entire rom is not encrypted. sp+entry point and opcodes are encrypted while vectors and data are not. Plus the key defines an address range for what part of the rom can contain encrypted data. The hard part is that opcodes and data are intermixed within...

The 6 slot is working good now?

That line is from openkey-cps2 firmware. Please be mindful of the complete context of the code. // There are only 10 unique combinations of the first 6 bytes // of all key data. In order to save about 800 bytes of flash // we are using the below lookup table for these 6 bytes. // Without the...

The board was recently purchased off ebay with known video problems. The board was in excellent condition, no physical damage or scratches. The video issue ended up being missing sprites, where some of the missing sprites would randomly show up sometimes. All ram and mask rom crc's test...

heh, you guys are learning that MV1A boards are shitty.

Assuming you aren't getting palette ram errors. I would check on the inputs/outputs of the 2x 74LS273's at U8 and U9 to the lower left of the bios chip. It should go palette ram data -> 273s -> resistors on the under side -> jamma rgb pins.

Kinda sounds like a dirty cart or slot. You might try (re?) cleaning both. Additionally try fully inserting the cart then backing it out a few mm and try it like that.

Both error codes point to the same thing 001100 - z80 never got the handshake (0x5a) response from the 68k 001101 - z80 got the handshake (0x5a) response from the 68k, but when the z80 tired to clear the latch after, it didn't clear Is it possible you have a floating data line from the latch...

If you can do both I would do both, but just m1 is fine

For eproms I use twistedsymphony's cross reference. I can never seem to find it on his site, but there is a copy here (3rd image in the first post) https://www.arcade-projects.com/threads/the-great-arcade-projects-dump-drive-of-2022.20110/

Getting only 2 beeps is weird, perhaps there is some issue talking to the ym2610. If its easy for you to update your diag m1, you can try this version https://www.mvs-scans.com/misc/neogeo-diag-master-next.zip It adds error addresses to the diag m1. After playing a beep code it will jump to...

The Z80 has the ability to clear the latched data that is waiting for it from the 68k. The error is indicating the z80 tried to clear the latch, but when it re-read the latch afterwards it wasn't 0x00.