How a 2332 rules ROM differs from a 2532 EPROM

The two are pinned alike except pins 20 and 21. On the 2332 both are chip selects (CS1, CS2) that must be high to read; on the 2532 pin 21 is Vpp and pin 20 is a single active-low enable, so the board needs those signals combined, inverted and some component-side traces cut and jumpered. Boards of the earliest DET PB03-D102 type should be converted to a single 2716 game ROM before attempting this.

Systems

• Gottlieb System 80
• Gottlieb System 80A

Related tips

• Fitting the 2532 test EPROM at U3 on a board without a piggyback
• U2/U3 rules ROMs decide which system a CPU board runs
• Ways to fit EPROMs at U2/U3
• Which System 80 test EPROM image to use
• Bench setup for the System 80 test EPROM
• Testing the DIP switch inputs with the test EPROM
• System 80 test EPROM LED flash codes
• Converting a D102 CPU board to take a 2716 game ROM

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