Neo Geo MV1FZ garbage screen and no click of death

skylab

n00b
Joined
Aug 30, 2024
Posts
2
Hi guys. I have a mvf1z board and I consolized it. I used it with a 161 in 1 cartridge. It worked very well for a few days but today I turn on the board and not works. I get this garbage:

1725004504174.jpg

No audio and no click of death. I get the same pattern with unibios 4.0, original bios and diagnostics bios. Without bios there is the click of death (obviously).
I checked data bus and address bus signals on cpu and ram with a logic probe, most of the address and data signals pulse but some signals don't pulse but stuck high or low. The CE and OE signals on the ram seem ok.
There are no broken traces between the RAM and the CPU buses. I replaced workind and backup ram but nothing has changed.
The board is in very very good condition, there are no traces of corrosion anywhere and the solder mask is perfect (compared to other boards in my possession).
What can I do or check? Thanks.
 

ack

Zero's Tailor
15 Year Member
Joined
Apr 9, 2009
Posts
550
Check the voltage on your 5V rail.
 

skylab

n00b
Joined
Aug 30, 2024
Posts
2
Check the voltage on your 5V rail.
5V voltage is ok on the jamma connector and in the ram/rom/cpu power pins. I have 2 power supply and others arcade boards, not a power problem :)
I also checked data and address buses of L0 and SFIX roms and all signals pulse. Palette ram and video ramd don't have floating pin and all signals pulse.
But I don't know if a bad video/palette ram or L0/SFIX rom can cause this problem.
 
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