MVS carts with frankenstein daughter boards

Hi

I think I got these back in 2011 time frame and kinda forgot about them. I originally thought they were hacks, but re-examining them recently I'm not sure.

I have 2 of them and unfortunately both give crosshatch screens



Both have the same daughter board which is labeled as "PERFECT LOCK SYSTEM VER 3.0". The Lattice chip is a programmable logic device (PLD) and the 2 smaller chips are octal bus transceivers.


I hole is the case was made to allow the daughter board to plugin



In both cases the SNK boards inside contain original roms, except the P1 rom is replaced by the socket/riser that the daughter board plugs into. The original P1 rom is plugged into the daughter board.


(The daughter board is rotate 90 degrees in the pic)

Here is the underside of the daughter board



Curious if anyone has seen these before and thoughts on wtf they would be doing.

-ack

These seem like hacks to me. I think someone was trying to alter or update the program. Although it seems like it would be a lot easier to just swap in an EPROM.

Are teh original games working? I mean: if you burn an EPROM with the original P1 file on it, or if you take the P1 chip on the riser cards and install it, do any of the games work?

Shame the daughterboard isn't working. The carts work when you just move the P1 from the daughterboard back to the cart, right?

aha2940 said:

Are teh original games working? I mean: if you burn an EPROM with the original P1 file on it, or if you take the P1 chip on the riser cards and install it, do any of the games work?

Click to expand...

Neo Alec said:

Shame the daughterboard isn't working. The carts work when you just move the P1 from the daughterboard back to the cart, right?

Click to expand...

Plugging the P1 rom directly into the riser socket doesn't get good continuity because the socket is expecting those larger square pins seen on the bottom of the daughter board, while the rom has the flat style. I will see if I can hunt down something to convert between them.

One thing I was thinking is that there could have been eproms in those empty sockets on the daughter board and the PLD either patched in the data from them or maybe somehow choose loading the original P1 or eproms. However it seems weird to call the daughter board "PERFECT LOCK SYSTEM" if thats what you were doing.

-ack

I ended up removing the socket/riser from the PROGTOP board and soldered the P1 rom into the P1 slot and the game booted/crc'd fine. Then I put it back the way it was and got crosshatch again. Oh well, probably something borked with the PLD or its expecting something in the empty sockets.


-ack

These were unofficial update kits sold to operators back in the day. Usually developed for the most popular, best selling, and highest revenue games. No different then say the rainbow roms for Street Fighter 2 or the Kombo kit for Mortal Kombat, or even the monster trucks for Daytona USA.

Fatal Fury 2 had one of these as well.