C128 Diag

Retro Rewind C128 Diag
Fig. 1: Retro Rewind C128 Diag

The 785260 based diagnostic cart was used by Commodore technicians in house to diagnose problems with C128(D/DCR)s.

When paired with a full test harness (dedicated C128 keyboard dongle required), the software exercises the CPU, system RAM, ROMs, dedicated ICs (SID, PLA, VIC, CIA, etc) and various I/O circuits of the C128. The test will report if something is bad and possibly display what IC has failed.

Refer to the manual below on proper operation and how to diagnose issues when using the 785260 cartridge.