Hi Guys,
Got a logic probe, Vs. schematics that I am trying to learn how to read, and beginning to learn about pcb repair with repairing the main side of a Nintendo Vs. pcb MDS-04-CPU showing a blue blank screen, the sub side works fine.
I have spent some hours probing around and have noticed the programmed 2764 eprom I have set in position 2B on the board at pin 26 is not in a flashing state but looks like it is pulsing rapidly instead but not in a regular on and off pattern, it never goes off and looks and very irregular, When I place the eprom on the sub side of the board in position 8B, logic probe shows normal flashing activity at pin position 26 as this side runs the game fine.
I replaced the socket at 2B, but the probe still shows pin 26 irregular pulsing.
This is where I need some help, looking at the Vs. Schematic MDS-02CPU I can't understand where the 2B, pin 26 is connected to and if the numbers 25-30 outside chip 2F are representing that with pin 26 going into pin 12 of the ppu chip at 2F?
Thanks for any guidance!
Got a logic probe, Vs. schematics that I am trying to learn how to read, and beginning to learn about pcb repair with repairing the main side of a Nintendo Vs. pcb MDS-04-CPU showing a blue blank screen, the sub side works fine.
I have spent some hours probing around and have noticed the programmed 2764 eprom I have set in position 2B on the board at pin 26 is not in a flashing state but looks like it is pulsing rapidly instead but not in a regular on and off pattern, it never goes off and looks and very irregular, When I place the eprom on the sub side of the board in position 8B, logic probe shows normal flashing activity at pin position 26 as this side runs the game fine.
I replaced the socket at 2B, but the probe still shows pin 26 irregular pulsing.
This is where I need some help, looking at the Vs. Schematic MDS-02CPU I can't understand where the 2B, pin 26 is connected to and if the numbers 25-30 outside chip 2F are representing that with pin 26 going into pin 12 of the ppu chip at 2F?
Thanks for any guidance!
