Multiplexed L/R (A/B) banks and wire colours
CPU transistors Q39-Q46 each drive two devices, one in the L (also called A) bank and one in the R (B) bank. L is mostly coils, R mostly flashers. Power from the PPB uses brown wires for L devices and orange wires for R devices.
Systems
Related tips
- The solenoid L/R select relay and transistor Q29
- 50 V coils use PPB TIP36c transistors, pre-driven from the CPU board
- Three-stage drive for 50 V coils
- Where the TIP122 drivers are on the CPU board
- How a coil or flasher is switched: PIA to TTL to pre-driver to driver
- Solenoid driver transistor positions on the CPU and PPB boards
- How the CPU-controlled lamp matrix is wired
- Test each lamp row driver with a test lamp
Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part One, Clay Harrell (pinrepair.com)