Spy Hunter troubleshooting experts

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Spy Hunter troubleshooting - FIXED!

I'm looking at a non-functioning Spy Hunter that was working when shipped. It has the MCR switcher adapter installed. The seller had the buyer check a few things before I got called out. I think the buyer messed with the switcher and cranked the voltage all the way up, as the +5 was reading over +6 at the switcher and +5.80 at the ROMs on the SSIO. I turned it back down to +5.15 at the ROMs, but it still does the same thing.

So - the game comes on, you hear the PG theme, the monitor comes up - and there is just scrolling garbage. It scrolls from top right to bottom left, is mostly blue, and usually has multiple "R"s interspersed in the garbage.

I pulled the board to take home for bench-testing, but was wondering if any MCR experts may have any ideas? Should I check the ROMs to see if any went bad from the high voltage? I tried reseating all the socketed chips and flexing the ribbon cables, but didn't see anything improve. Not sure if that would have taken care of everything before the buyer messed with the PS.

I did notice that one of the pins (yellow wire - Pin 14 maybe?) on the power connector housing looked black, like it burned or overheated. I tried flexing it to see if a bad connection there was an issue, but didn't get anything different.

Someone needs to compile a video list of pics of various MCR problems and how the present themselves on the screen...
 
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mcr boards are fun... i am finishing up a tapper now, i have had to replace many parts on this board, and last part is the sound, which was working, but now it has stopped again, so i am leaning towards an issue between the cpu and 8910(s) but (i have to order some 74ls138's)

anywho, if you keep seeing scrolling blues, sounds like its stuck in a reset loop.

common problems i see is bad video ram (93422's)

i need to make something to test them..
 
Check the reset circuit leaving the power supply. I know Spy Hunter needs a working reset circuit. It's the only purple wire that exits the two 15-pin connectors at the power supply. I know the reset circuit is generated on the small circuit board of the switcher adapter. It should read approximately 5VDC (at the purple wire).

Edward
 
Check the reset circuit leaving the power supply. I know Spy Hunter needs a working reset circuit. It's the only purple wire that exits the two 15-pin connectors at the power supply. I know the reset circuit is generated on the small circuit board of the switcher adapter. It should read approximately 5VDC (at the purple wire).

Edward

Unfortunately, I don't have the entire game, just the game pcb. If it works on my bench, then I'll go back to the cab and check the adapter...
 
Okay, I've got it in RA</ROM test via dip switch, and the LED is flashing. So - how do I know whether it is "FAST" or "SLOW" flashes? I'd guess I'm getting 2 flashes per second.

And is there any other indicator as to WHICH failed? Or do I just have to go through all of them?
 
I pulled 2 ROMs - one from location 10G and one from location 10D. The 10G ROM came up in ROMIdent as a possible match for 4 different games - none of which were Spy Hunter. The 10D ROM came up as "Not Found". I'll have to go through them all, but either I have mass ROM issues from the high voltage, or something is wrong with my identifying....
 
Some general thoughts/questions:
- Do you see the test patterns after the main CPU comes out of reset? Just wondering if you've seen evidence of it executing code or not; the test patterns would also help verify the video output HW functionality.

- Regarding the scrolling garbage - is the CPU actually resetting (as in an endless self-test loop)? Or is the video output just scrolling garbage? Does it play blind? Since you didn't mention seeing the test patterns repeating, it sounds like it's not actually in a reset loop (watchdog or otherwise). I'm guessing it's either pulling garbage sprite/tile data from ROM, or the video RAM is corrupting.

- Do you happen to have a Fluke 9010a and Z80 pod? That could help narrow down the failing subsystem pretty quickly. Shoot me a PM if you're interested in borrowing mine.

- Some questions for the owner - is this the same failure he saw when it got delivered? Or did the failure change at some point (e.g. whenever he dialed up the PSU)?

I haven't debugged an MCR game, but I'm guessing something got hosed in the RAM or ROM subsystems (although not a complete failure, since it appears you're somewhat functional .. I would expect a diag code or watchdog resets if either were completely toast).

LeChuck
 
I pulled 2 ROMs - one from location 10G and one from location 10D. The 10G ROM came up in ROMIdent as a possible match for 4 different games - none of which were Spy Hunter. The 10D ROM came up as "Not Found". I'll have to go through them all, but either I have mass ROM issues from the high voltage, or something is wrong with my identifying....
Are you using the web-based ROMIdent?
http://romident.ki4swy.org/

I tried this experiment with my MAME 10G/10D ROMs and they matched to Spy Hunter (and nothing else). I'm not sure if you can attach the ROM images you're pulling here, but it would be interesting to binary compare them with good images to see what's changed.

I don't have a clear picture yet of what the failure mode is, but I would expect mass ROM failures to result in an endless watchdog reset loop (since the CPU would come out of reset and quickly go off into the weeds).

LeChuck
 
I didn't have much time last night. I tried checking with the web based romident on coinop.org..
 
I dug up another boardset that had a little damage to the SSIO. I swapped the two bottom board in with the original SSIO and the game now boots to the "Input Coin" screen, but then after a couple seconds it seems to freeze with just the road and grass showing. No attract mode or anything. Putting the game in RAM/ROM test now just gives a solid yellow LED - no blinking.

Thoughts?
 
Okay, I have it running now in attract mode on my bench. :)

However, I can't get it to coin up on the bench. I've ground the coin pins (pins 1 & 2 of J4 on the SSIO), but it doesn't credit up. I put it into test and verified all the inputs were working, including the coins, and they do register.

Is this something that the PCB needs to be in the cab with all the other boards attached to do? I've verified that grounding the coin 1 pin at J4 does cause pin 17 of F2 (74LS244) to go low. I can't tell from the datasheet if that is supposed to affect the output pin (pin 3?) or not as I just get pulsing on that pin. No change when I ground the credit pin.

Do I still have a problem with the boards or not?
 
Got it.

I was reading some posts about Spy Hunter not coining up, and found reference to the three chips to the side of the main processor on the CPU. Although i had already replaced them and replacing the Z80B had caused the game to start working, it turns out that the Z80B I put in still had issues, and another caused all my inputs to start working. Game now credits and runs. Of course, since the Absolute Position PCB isn't attached, it just veers to the side and crashes, but still - good news...
 
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