Making a System 80B CPU board run an earlier game (or the reverse)
This is a sizeable job: the 80B display jumpers must be removed or changed, display chips Z19 and Z21 to Z25 refitted, and the U2/U3 piggyback board given an EPROM with System 80 or 80A rules code. The display hardware and rules ROMs are the main obstacles.
Systems
Related tips
- U2/U3 rules ROMs decide which system a CPU board runs
- Swapping CPU boards between System 80, 80A and 80B
- Which System 80 CPU board goes with which games
- Big House and later use the MA-1133 System 80B CPU board
- System 80 CPU board main chips
- Reading the System 80 CPU DIP switches
- System 80 CPU board revisions D102, D107 and D20869
- System 80 CPU board passive parts and diodes, board-wide
Source: Repairing & Upgrading Gottlieb System 80 Pinballs from 1980 to 1989, Part One, Clay Harrell (pinrepair.com)