how to swap T-unit games

mecha

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ok, I'm not trying to promote the sacrifice of unsuspecting and innocent NBA Jam boards, but I took a frankenstein MK T-unit board and was able to successfully swap to an NBA Jam board.

my MK T-unit was in fact an MK2 that for whatever reason was converted to MK1 by the previous owner, and I bought it with a multitude of strange issues. I was able to fix most of them until the board's video sync started to heavily freak out. I felt NBA Jams are a dime a dozen, so for the time being I did a swap.

if you directly swap the roms though, both games will not boot at all. as per zenomorp's quick response advice (while serving for our great nation overseas :)) you also have to swap the graphics chip too! this is the PLCC chip nearest to the JAMMA edge, make sure you have a PLCC extractor otherwise you will break the socket if you attempt to use a flathead.

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upon doing this, I got myself a working MK T-unit, and the NBA Jam told me to go fuck myself. until the next time...

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I hate my PLCC extractor i got with a really old radioshack PC tool kit, i love the kit just hate the chip pullers they gave me, i've used it on a few PC bios chips but never had good luck with pulling the one on a board i had that didn't end up needing the chip pulled anyways lol.

Great info, I figured they were swappable and was even thinking about doing it if i couldn't get this last MK1 board working. I just figured you pull all of the chips and swap them not just the major roms.

Edit: oh yea, when i did pull the PC bios chips, i ended up bending the pins one time out of 3, not bad but still wasn't happy.

Circled in Red
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there's another little IC above the roms, the numbers were different between NBA Jam and MK, so I'm guessing that's the lone security chip you have to change. the other small IC next to the graphics chip you pull had the same numbers on both boards, so that might be a universal T-unit one.

yeah, when zenomorp told me that I was like "ok, maybe..." and then I looked at the labels, sure enough, they had different numbers on them. at least Williams/Midway spots you that, lol, permitting all your labels are still intact of course.
 
for Broods, and any other suspecting rom voltage testers out there...

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those are the two pins that you probe for checking +5 lol. make sure you don't slip and start bridging pins. :)

make note of the U-shaped notch.
 

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for Broods, and any other suspecting rom voltage testers out there...

attachment.php


those are the two pins that you probe for checking +5 lol. make sure you don't slip and start bridging pins. :)

make note of the U-shaped notch.

lol, woot thanks :D
 
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