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Vanløse, Copenhagen, Denmark
Mathematician. Working programmer/system developer. Nerd. Married. Father of 3.

14.2.13

Capcom Gun Smoke Bootleg Repair Log

All I used for this easy 'rep' was

my flathead screwdriver; actually my favourite tool...really love it <3
my trusty soledering iron
and a bit of common sense
I got this board as a part of the trade for this bootleg 1942 that I'd just recently fixed. I was told that the board booted and coined up, but when pressing start, it would freeze. The pinout (2 x 28) was a bit strange; not like anything I'd seen before (certainly not Capcom Classic)


(the key is at 8 like on Capcom Classic; pin 26, 27, and 28 on parts side is GND, but on solder side it's only 27 and 28). However the game came with a JAMMA adaptor that made it boot, so I just started by using that.

Just as described, that game booted up just fine


and also coined up


But when pressing start I got this screen


for a second or two before the game rebooted (the watchdog jumped up bit the main Z80 in the butt };-P). The same thing also happend when the game ran in attract mode and was to show the in-game sequence.
So I started with the basics: Visual inspection, dumping ROMs and reseating all socketed ICs. During this, I quickly found this area interesting


Somethig didn't look right; ROMs no 3 and 4 facing one way, while 5 was facing the other. When I pulled no 5, it was obvious by looking at the circuit lines, that it had been inserted the wrong way. Often this causes the ROM to get fried, as they are very sensitive to getting polarity reversed. So I turned it around, crossed my fingers, and got this


Even though the screen look garbled, this was the intro sequence for sure, and after that the actual game also ran...SWEET! };-P (no sound though).

I was finish with basics on the main board, so turned to the graphics board. Here I found this


This didn't seem right either. In the first row we have 7, 6, 8, 9 and in the second row 10, 11, 12, 13... Well I'll be damned, if that first row shouldn't read 6, 7, 8, 9 instead. So I tried switching the two


and now had a garble-free intro sequence


The game itself played fine, but the cowboy was only able to shoot forward and left. A quick look at the adaptor, and I saw, that only two buttons were wired on the JAMMA fingerboard. Now I couldn't find that strange pinout anywhere on the net, so I just tried poking a grounded wire at the different unused pins. And on pin 20 on the parts side


I hit the jackpot


So soldered an extra wire (the white'n'red one) on the adaptor


The last thing I needed for this to be perfect, was sound. There was already wires from two pins on the edge connector to SPEAKER + and - on the fingerboard. So from previous repairs, I know that it's smart to try and switch the wires (when working with a SuperGun and not a cab with a speaker) before trying anything else. And because we have an adaptor in play, luckily that's quite easy. And, PRESTO! the sweet sound of gunfire filled the room };-P
The game now plays perfectly, and I ended up with a pinout looking like this

If anyone out there has more info on this pinout, don't hesitate to leave a comment };-P

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