Got a pic of a Viper Phase 1 PCB?

[rjosal]

I picked up a non working Viper Phase 1 including mobo. It's a Dream Island / Asia version. I've dumped the 6 socketed roms and they aren't found by romident, but they work fine in MAME (anyone want them?). The issue is garbled sprites, everything else works fine. I tried putting USA roms in the cart and popping it in a USA mobo and it works the same, with garbled sprites, so that tells me there is something wrong with the cart. Does someone with this cart mind taking a pic of the component side of the pcb? I *think* all the regions are the same. I want to make sure there isn't a cap missing or something stupid like that.

Here's mine:


EDIT: Here's a much better clearer picture. Stupid iCloud doesn't let me get a raw link to it though. I cleaned the dirt off the cartridge connectors first.
https://www.icloud.com/photostream/#A7J ... 67E73278BC

[system11]

Those ROMs need to be sent to the MAME people, I can roll them into the driver and submit the change.

As for likely faults, cracked solder joins on that surface mount chip are a high possibility - it's certainly not going to be something like a cap. Check the SMT ram/rom too (can't make out which it is).

[PC Engine Fan X!]

Fabtek USA distributed the Viper Phase 1 U.S.A. Jamma conversion kits back in 1995. I've got one of those barebones SP1 mobo + SP1 cart of VP1-USA in my collection. Works 100% like a charm as usual. Some shmuppers would rather prefer to play the original JPN region Viper Phase 1 "Old Version" but that's em' folks. When my local arcade had gotten ahold of a VP1-USA conversion kit in 1995, it was in the same Dynamo upright from 1995 until 1998 (and still quite a popular arcade shmup title all those years). The top ten ranked high scores would be in the high 2 million+ easily.

You might be aware of the Viper Phase 1 "New Version" SP1 cart that was sold in Japan -- has the same gameplay and game mechanics as that of the USA region VP1-USA cart indeed.

PC Engine Fan X! ^_~

[rjosal]

I also got an unknown (0x28) region Raiden Fighters in the deal too, it's a funky board with only 2 socketed ROMs I think. The mobo has two broken pins though so I need to wire that up first to test it out, and hopefully find out what this unknown region is. I haven't tried them in MAME yet either, though I have dumped the ROMs. Hopefully I'll have some time this weekend to mess with it. Where shall I send these?

I thought the QFP or one of the 3 OBJ ROMs may have a bad solder joint, and interestingly the ROMs look like they were removed and put back because it's not super clean, but I didn't see or find any faults with a multimeter. I think there was a cold solder joint on one of the cart connectors though, so I'll try cleaning that up, though the multimeter shows continuity.

A missing cap wouldn't cause this huh? I'm pretty new to repair, I just wanted to eliminate that as an issue because there are a couple spots where it looks like there should be caps, just for consistency's sake. I saw a repair log for a raiden DX board with the exact same symptom which was a broken/disconnected trace so that might corroborate a bad solder joint.

[pcb_revival]

Viper Phase Japan.

Are the solder connections on your cartridge okay, the image makes them look to have slight corrosion.

The four blue components at the edge of the cart connectors are the same as the component at point C1 as far as I can make out.

[rjosal]

Thanks for the pic! I'm "missing" 16 caps including the 4 tantalums. What is the purpose of these caps? I might guess that they are missing for a reason, like maybe that the chips were removed and reattached. I added a link to a much better pic of my board to the OP, after brushing some dirt off.

So I plugged in the 0x28 region Raiden Fighters after manually wiring the two broken pins together, and it worked alright, but I was unfortunately greeted with a "Country Code Not Recognized" title screen, instead of the expected "You Have Won A Copy Of Raiden Fighters 4!". I replaced the dream island seibu1,7 roms with my roms and MAME did the same thing.

Title Screen: https://www.icloud.com/photostream/#A7J ... 0393487378
PCB: https://www.icloud.com/photostream/#A7J ... E3B568E1E5

I guess that means someone was mucking with it, but the mobo flash chips don't look like they were pulled so I would have expected a checksum error.

Edit: I've just verified the "unknown region" ROMs are identical to the Dream Island version ROMs apart from the 0x28 region. So then I got thinking maybe that was changed to make the cart region-free, but of course that was too good to be true. I burned the Dream Island region, and the mobo now gives the checksum error, so even the mobo has the crazy region in flash!

[rtw]

The 0x28 is interesting. It is actually China according to the MAME source code. I guess the board was originally running a different ROM set which had the region string for China.

[rjosal]

The 0x28 is interesting. It is actually China according to the MAME source code. I guess the board was originally running a different ROM set which had the region string for China.

I see that comment now. I wonder what the references were. I'm going to guess that perhaps Seibu made a license (and 0x28) region for one of the other games and RF got left out, otherwise why would the title screen show unrecognized region? That would at least support the issue of how my mobo ended up with 0x28 region, because otherwise that would be a pointless stupid hack. I'd like to see a ROM that has that region, and displays it on the title screen.

Back on topic, anybody have any comments on my missing caps? Should I replace them, or are they "extra" like all the screws you're left over with after you put something back together you just took apart?

[system11]

They're just for filtering and usually the first thing to go when things get licensed, bootlegged or cost-cut.