Memory test (test 20) result codes

"99" means all memory passed. Otherwise the display names the bad chip: 5101 is RAM Z5, 2332-1 the U2 rules ROM, 2332-2 the U3 rules ROM, 6532-1/-2/-3 the RIOTs U4, U5 and U6, and 2716 the game EPROM. The player 2 display shows the game EPROM checksum. On a D102 board converted to a 2716 a bad game ROM is still reported as 7641.

Systems

• Gottlieb System 80
• Gottlieb System 80A

Related tips

• System 80 test EPROM LED flash codes
• Random errors on early System 80/80A CPU boards: add the R/W pull-up
• Which System 80 CPU board goes with which games
• Later single-PROM CPU board won't boot in an early System 80 game
• System 80 and 80A CPU boards swap only with the matching U2/U3
• Making a System 80B CPU board run an earlier game (or the reverse)
• Replace the decoupling capacitors on the CPU and driver boards
• Reading the System 80 CPU DIP switches

Source: Repairing & Upgrading Gottlieb System 80 Pinballs from 1980 to 1989, Part Two, Clay Harrell (pinrepair.com)