As I've posted on here me and a friend recently got a Contra cabinet. When we first got it home it would just display the RAM OK ROM OK test screen and thenstart the game and then restart eventually. Well the wiring was done with lots of electrical tape so I figured it was a lose connection or something, but never found anything. Started it up again, and it worked for several hours. Either way we wanted new wiring in there since it was all done with electrical tape before. When it was restarting though it was displaying garbage of was on the screen for a few seconds before restarting. We ordered this wiring harness off of this site: http://www.jammaboards.com/store/jamma-full-cabinet-wiring-harness-loom/prod_146.html We take out the old which is kind of different because it has tons of plugs and the monitor plug was quite a bit bigger compared to the new wiring kit we ordered. Anyways we hook up the power supply, plug in the jamma connector, and wire the new wires to the old plug for the monitor. Turn on the system... The monitor/marquee light turn on, but no Contra. Hook up the old wiring harness, and we get the same thing. So considering I don't have another machine to test the board in does it sound like the board was dying and finally kicked the bucket or does it sound like I'm doing something stupid. The board also did have a couple rust spots, on what I'm assuming are the processors. http://img203.imageshack.us/img203/8146/contrat.png Anyways hope I can get some answer, everything else so far had been going so smoothly. =(
First make sure your wiring is correct and make sure you connect as many of the grounds as possible, with making anything with arcades the rule should more grounds = good. I would test the PSU and make sure you are getting 5V off it, as this can be a major issue of board problems. Measure it under load on the JAMMA connector (without a load it might give you a much higher reading). If it's below or above 5V by more then .3v then adjust it (it should have small knob to adjust it). Do this first then let us know what happens. 12V and -5V aren't so important as they are generally used by the amps, but measure them anyway just to see if the PSU is sick.
That's the weird thing though the wiring diagram in the contra instruction manual I have says -5V is not used. Here's the manual I'm using, and the wiring diagram is on page 5: http://tamdb.net/index.php?page=ManualDetail&id=2470 I'll test the voltages maybe tomorrow or something. I don't own a volt meter, and not sure if anyone I know in town has one. Worst case I have to buy one.
