[ukvac] [Tech] TMNT Pcb
Hi guys, Any help much apreciated on this Konami TMNT pcb
Ram G8 (TMM2018) reports bad then game resets in an endless loop every
3-4seconds
I've whipped out the ram, socketed and replaced with a tested working 2018
Ram still reporting bad.
It looks to me like everything (address,data,WE,OE) are controlled by the
large 200odd pin surface mount custom. CE is tied low.
I have compared the signals with a working board during the self test
procedure to the point where the faulty board resets.
The address lines all have plenty of activity.
The OE line pulses constantly, first quickly then slows down (as it does on
the working board)
The WE pulses once breifly near the end of the self test (as it does on the
working board)
On the working board there is activity on the data pins
On the faulty board the datapins stay fixed, some high and some low.
I injected some pulses into the WE during address activity to fill the ram
with random crap, then for the next few cycles the random crap is played
back on the data pins as the OE is pusled. (the wierd thing is that during
pulsing the WE there is activity on the data lines ?!?)
After a few cycles the data lines go back to their either high or low
states, and stay there, then the board reports G8 bad and resets.
Anyone any ideas or is the board screwed due to buggered 200pin surface
jobby?
Thanks in advance
Luke
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Hi guys, Any help much apreciated on this Konami TMNT pcb
Ram G8 (TMM2018) reports bad then game resets in an endless loop every
3-4seconds
I've whipped out the ram, socketed and replaced with a tested working 2018
Ram still reporting bad.
It looks to me like everything (address,data,WE,OE) are controlled by the
large 200odd pin surface mount custom. CE is tied low.
I have compared the signals with a working board during the self test
procedure to the point where the faulty board resets.
The address lines all have plenty of activity.
The OE line pulses constantly, first quickly then slows down (as it does on
the working board)
The WE pulses once breifly near the end of the self test (as it does on the
working board)
On the working board there is activity on the data pins
On the faulty board the datapins stay fixed, some high and some low.
I injected some pulses into the WE during address activity to fill the ram
with random crap, then for the next few cycles the random crap is played
back on the data pins as the OE is pusled. (the wierd thing is that during
pulsing the WE there is activity on the data lines ?!?)
After a few cycles the data lines go back to their either high or low
states, and stay there, then the board reports G8 bad and resets.
Anyone any ideas or is the board screwed due to buggered 200pin surface
jobby?
Thanks in advance
Luke
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/