Switch row trace map from CN10 to the 4011 chips
Each row runs CN10 pin, RA16 pin, through a 1k resistor of RB5 or RB6, to a 4011 input pair. CN10-1 row 8 to 6J pins 1-2; CN10-2 row 7 to 6J 12-13; CN10-3 row 6 to 6J 8-9; CN10-4 key; CN10-5 row 5 to 6J 5-6; CN10-6 row 4 to 5J 1-2; CN10-7 row 3 to 5J 12-13; CN10-8 row 2 to 5J 8-9; CN10-9 row 1 to 5J 5-6. RA16 pins 2 to 9 follow CN10 pins 1 to 9 in order, skipping the key.
Systems
Related tips
- Switch column trace map from CN8 to the 74LS244
- CPU connector CN10: switch row pins and wire colours
- Switch row (return) circuit on the CPU board
- Test the switch row inputs with a diode jumper
- Pressing one switch closes the whole row: bad 4011 chip on the CPU board
- Switch row or column error: CPU board or playfield?
- Which switches are outside the switch matrix
- Check the switch matrix with a logic probe
Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part Three, Clay Harrell (pinrepair.com)