Where the main chips sit near the CPU board batteries

Below the batteries are the 6808 (or 6802) processor at 3D and the CMOS RAM (2064C, 6264 or 6116) at 5D. The game EPROM sockets are at 5C and 5B; some games leave 5B empty. A GND test point is above the batteries and a B+ test point is to the right of D25.

Systems

• Data East CPU Version 1/2
• Data East CPU Version 3
• Data East/Sega CPU Version 3b

Related tips

• Where the TIP122 drivers are on the CPU board
• Combining two-chip CPU code into one 27512 for 5C
• Other CPU jumpers and what they set
• Bench-testing a CPU board on +5 V
• CPU boards are only downward compatible
• CPU EPROM jumpers J4 and J5
• CPU board versions 520-5003-01, -02 and -03
• CPU board PIA positions and jobs

Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part Three, Clay Harrell (pinrepair.com)