Mario Brothers Pcb won't boot

dyno

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Picked up a Mario Brothers board and it does not boot. When I turn it on I get a bit of a song and here is what comes up on the screen. Nothing happens when I try to coin it or push the test button. I have been plugging away at it with not much luck. Any ideas?
 

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Picked up a Mario Brothers board and it does not boot. When I turn it on I get a bit of a song and here is what comes up on the screen. Nothing happens when I try to coin it or push the test button. I have been plugging away at it with not much luck. Any ideas?

When a game is completely dead always check your voltages first to make sure the power supply is doing its job. From there I would check and reseat your CPU and program ROMs.
 
"From there I would check and reseat your CPU and program ROMs."

+1 I bought a DK3 machine really cheap because it would not boot up. Pressed on the chips, and it fired right up. Listen to that snappy sound when you press on the chipsets. That should be non existent after you press on the board and everything is reseated properly. No need to take them out, just press on them if you have not done this already. Do this with the power on or off. If you do it with power on, just be careful not to short anything out to the chassis. Hope this helps. Good luck.
 
Power getting to the board is good already checked that and also have reseated the CPU and program ROMs with no luck. I never seem to have an easy fix like that:)
 
If you have a logic probe check the reset pin on the z80 and see if its pulsing and also check to make sure you have a toggling clock signal.
 
I do have a logic probe so I will check those. I noticed when using my logic probe that the data lines on the the IC at at 7H on the cpu board aren't doing anything. The address lines are pulsing on it, I replaced it hoping that would solve my problems but no luck. Also the ic 7C on the video board which is connected to 7H on the cpu has not activity on the data lines also.
 
I do have a logic probe so I will check those. I noticed when using my logic probe that the data lines on the the IC at at 7H on the cpu board aren't doing anything. The address lines are pulsing on it, I replaced it hoping that would solve my problems but no luck. Also the ic 7C on the video board which is connected to 7H on the cpu has not activity on the data lines also.

Check the data lines on the Z80 as well. That feeds 7H as well as the DMA chip.
 
I checked the clock on the z80 and it is pulsing. The reset line goes from low to high and stays high but does not pulse. I followed the reset line from the z80 which connects to the reset on the m58715 ic and the reset there doesn't pulse also. Pins 2 and 3 on the m58715 are connected to the 11 MHz crystal which isn't pulsing so I used a 12 MHz crystal I had and put it in place of the 11 MHz and still the crystal doesn't pulse. Could the m58175 ic be causing the crystal not to pulse,which in turn is causing the board to be dead? I also checked the data lines on the z80 that goes to 7H and they are pulsing.
 
Crystals typically won't have enough of a voltage swing to trip logic probes...

Check pin 6 on the Z80. If you have a signal there then the clock is working.

Probably a dead Z80-DMA chip.
 
Not having a replacement z80dma yet I poked around with my logic probe on the z80dma on the board.Noticed a handful of address lines aren't pulsing on it which in turn the corresponding address lines on the z80 aren't pulsing either. Hopefully replacing the z80dma fixes this issue.
 
Still waiting for the DMA ic but did some more poking around with the logic probe and discovered that the address lines on eproms 3F and 3J on the video board are dead.
 
Still waiting for the DMA ic but did some more poking around with the logic probe and discovered that the address lines on eproms 3F and 3J on the video board are dead.

Have you tried swappng the Z80?
 
Finally got the replacement z80dma ic and replacing it didn't fix my problem. Still getting no activity from the address line on 3F and 3J roms on the video board.
 
Well continuing to work on this, on the z80 the all the pins that are suppose to be low lgic are all high. Like the wait, nmi, int etc. It's not the z80 becuase I have swapped it out with a few working ones that I have.
 
Still trying to figure this out, the address line 1,2,3,5,39,40 are all showing logice low on the probe and not pulsing. Also the wait, nmi are stuck on lgic high. Tried to swap the z80 with no luck, what should I be checking next?
 
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