Hot Hand
Stern Electronics, 1979I just did the battery corrosion kit, it cleaned up pretty nice. I get the quick flash and then the 7 flashes. After that some lights come on and nothing else. No displays. I'm pretty sure the other boards are fine, it was working with an Alltek replacement. I read somewhere to try without the sound board attached. Same issue.
Sound board issues would more than likely cause the MPU LED to lock on. I have same questions as Billc479 did you change male connectors on this board?
If displays worked before they should work now at least as far as being on. Power for displays dose not go thru the MPU just the data for the segments.
Displays have a glow, no digits. I replaced the male header in the corrosion area, reflowed the rest. I will check back with voltages.
Reflowing the connectors dose not make the mating surface of the connectors better. They erode over time. Reseat J1 and see if that causes a difference.
Voltages seem ok,
TP1 5.2
TP2 12.7
TP3 21.2
TP5 5.2
Reseating J1 makes no difference.
I will pull the board and give it another good inspection while changing out the remaining header pins.
When this board was in the game did it go into test mode? If you set dip switches all to off would it enter factory test mode?
I changed out all of the header pins and cleaned up a couple solder joints I didn't like. Unfortunately, no change. Maybe the battery damage is too much? I cleaned up one of these in worse shape a few years ago and it was successful.
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can you swap in another 5101 ram if you have? i have had seen some 5101s pass a neoloch and the power on self test, yet crash when attract mode hits (too slow??). I notice your 5101 is AMI too....
I tried 2 different 5101s. My last 2 in the bin, both had question marks on them. I will try and dig up another or pull from a working game. Thanks.
I did have a weird (to me) issue with one of my bally machines - I put in an NVRAM and now the MPU and machine boots up fine. I am assuming there was something corrupted in the 5101. Since the machine worked after the swap, I never tried to figure out why it didn't work before.
Quoted from Billc479:I did have a weird (to me) issue with one of my bally machines - I put in an NVRAM and now the MPU and machine boots up fine. I am assuming there was something corrupted in the 5101. Since the machine worked after the swap, I never tried to figure out why it didn't work before.
NVRAM modules like mine have trace redundancy at the data pins. You could have a bad socket that NVRAM could "fix" if it is one of the Di and Do pins not connected together at the PCB like they should be (usually pin 11 and 12).
Quoted from Shredso:I tried 2 different 5101s. My last 2 in the bin, both had question marks on them. I will try and dig up another or pull from a working game. Thanks.
Two rams with the same symptoms I would think the problem is somewhere else. If the zero cross generator is out of time, the software can crash as soon as attract mode starts. Can you check the zero cross for 120hz? Need a real transformer / game to see this.
You may want to check out the dip switch blocks. It should have gone into test mode. I've had a board I was ready to pitch and it was the dips. Here is another thread where the post boot problems led to the dips:
I just fixed a -35 with a similar issue.
https://pinside.com/pinball/forum/topic/bally-35-board-switch-issue
This board would not go into factory test either. No switched would respond at all.
My personal opinion is you have a short between J1 and U10.
I have seen bad roms or rom connections that would have the checksum check check out. But have the game crashing after flash seven.
Resurrecting a 9 month old thread.....
I figured I'd give this another shot. I jumerped the board for a 2732 to eliminate the ROM being bad and eliminate one socket. It does the same thing. 7 flashes, then a few controlled lamps lock on. I will read through those linked threads and dig out the o-scope and see if I can figure out how to use it. Ha!
After the 7th LED flash, does the LED go out completely or does it stay dimly lit?
I would check the following signals on the MPU board with your scope for approximate correct frequencies:
Pin 18 of U10; 120Hz - Zero Crossing Detector signal
Pin 40 of U11; 320Hz - Display Interrupt Generator signal
The symptom you're seeing with attract mode not proceeding can be indicative of issues with the zero crossing signal.
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