hello
i have another board with some problems
it is a mv1fz,the first time i resolve a click of death with garbage screen.it is a bad 74hc259,so replace it and now i have a white screen only.i replace with new 74hc32 ,new nec d4990 ,new 68k but the same thing
i check level state of 74hc32,i found with probe sonde
1 H 14vcc
2 L 13H
3 H 12H
4 H 11 H
5 H 10H
6 H 9H
7 GND 8H
there is activity on sp1 eprom, rams ,i will check another day with oscilloscope
so do you have an idea about this problem?
thanks for your help
i have another board with some problems
it is a mv1fz,the first time i resolve a click of death with garbage screen.it is a bad 74hc259,so replace it and now i have a white screen only.i replace with new 74hc32 ,new nec d4990 ,new 68k but the same thing
i check level state of 74hc32,i found with probe sonde
1 H 14vcc
2 L 13H
3 H 12H
4 H 11 H
5 H 10H
6 H 9H
7 GND 8H
there is activity on sp1 eprom, rams ,i will check another day with oscilloscope
so do you have an idea about this problem?
thanks for your help
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