CPU chip types: 6800 on System 3/4, 6802 or 6808 on System 6/7
System 3 and 4 boards use a 6800 or 68B00; System 6 and 7 boards use a 6802 or 6808, and the two families do not swap. On System 6/7 a 6802 or 6808 can go in without jumper changes if the board shipped with a 6808. A 6808 has no internal RAM, so it needs J1 fitted, R4 removed and a 6810 RAM at IC13. Only on System 6 can a 6802's internal RAM replace the 6810 at IC13 (J1 out, 4.7K at R4).
Systems
Related tips
- CPU still will not boot after the basics
- A 6802 CPU chip works in place of the 6808
- System 6/7 sound board can take a 6802 in place of the 6808 and 6810
- Replacing the 6802 CPU with a 6808
- System 6/7 CPU: no clock at the 6802/6808
- Obsolete chips on System 3 to 7 CPU boards
- Keep spare 6800, 6821 and 5101 chips
- System 9: is the sound fault on the CPU board or the speech board?
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Two, Clay Harrell (pinrepair.com)