Ghostlop MVS cart, broken colors and loses sync

[HeavyMachineGoob]

Got a weird issue, trying to make a Ghostlop cart on a former Puzzle Bobble bootleg cart. The boards used are PROG42G and CHA42G.

Ghostlop uses 2x 4MB C ROMs. I split those C ROMs to get 4x 2MB C ROMs. Now yes I know all about CHA42G requiring C rom rearrangement if using 2MB roms, which I did do prior to burning the chips. I split all the files down to 8x 1MB, then reassembled those into 2MB files according to the instructions for CHA42G.

CHA42G - NeoGeo Development Wiki

wiki.neogeodev.org

The issue I'm having is the graphics are really broken. Tiles look correct, but the colors are all wrong and even stranger, the game often loses sync. Eventually the game will crash to an illegal instruction on the UniBIOS. I haven't tested on a stock BIOS yet.

I'm a bit at a loss here, not sure what the issue is. Yes the MVS board works fine, this is a game specific problem.

Pictures:

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imgur.com

https://imgur.com/4FVETry

https://imgur.com/P0OKKBm

https://imgur.com/YE4ZfdZ

https://imgur.com/0CTSV8e

https://imgur.com/9t3OU2X

 

[Neo Alec]

The PROG looks really dirty. The Puzzle Bobble boot functioned fine before you did the work I take it?

 

[Neodogg]

Anyway to verify the burns were correctly done?

 

[HeavyMachineGoob]

This PB bootleg didn't actually work before swapping the roms, it would boot to crosshatch, meaning no P ROM detected at all. Putting in a Ghostlop P1 rom does somewhat work though so I wouldn't expect the board to be bad. The Puzzle Bobble P1 was an exposed EPROM, probably got partially erased.

Only rom I can verify is the P1 ROM using the UniBIOS, don't have an option for the other chips, don't have an eprom burner that can read 29F1615, hence the buyicnow stickers, but those are usually good.

What's really frustrating is this the second of two carts I've tried to make as Ghostlop. The other cart uses PROG-G2 and CHA42G-2C. Yes I rearranged the C ROM data there too, yes I removed the 74LS245 and PRO-CT0 chips from, the PROG-G2. This cart has the same Ghostlop issues and this donor did work correctly originally.

So I'm stuck wondering what is the exact cause. I've tried multiple P1 ROMs on different EPROM chips.

Also attached is the UniBIOS CRC check. Yes I see it says NG for no good.

I thought PROG42G and PROG-G2 could accept a 1MB P1 ROM without a 74LS08. Isn't the LS08 just used for 2MB P1 ROMs?

I tested the rom files in an emulator, they were fine. Got the romset from winkawaks. Is their romset actually bad?

Edit: I forgot about the jumpers for the P1 rom, they look to be incorrectly set, going by this example Ninja Commando that uses a 1MB P1 rom. don't mind my ineptitude.

File:Ninja commando set1 b1 front.jpg - MVS

www.mvs-scans.com

Would still love to know why it doesn't work on PROG-G2, whenever I get a SMD 74LS08 I can try installing that.

 

[HeavyMachineGoob]

Update

Sure enough, the cause was incorrect jumpers. Need to have only the 8M jumper active. Stupid me. Game works correctly now.

Except I found a few graphics were corrupt, others were fine. I discovered a broken trace on the back of the CHA42G board, which I've fixed.

The other problem I am now able to notice is broken music and sfx. There are no V ROM jumpers on the PROG42G board. I went back to my usual, check other games to see what they do. I've checked many games that use PROG42G but none use more than 1MB per V ROM slot. I think I will have to split the V1 ROM. Probably is possible to rewire the board but I'm not up for that at the moment.

Other than that, i will call this project fixed. Here's hoping I can get my PROG-G2 Ghostlop working too.

Edit: figured out the PROG-G2, it was both an incorrect jumper and a bad P1 rom burn. Only figured out the jumper after getting a new P1 rom.