Let's build up and test Sven's (@svenpetersen191) Commodore Diagnostic Test Harness PCBs. They are used in conjunction with the Commodore Diagnostic ROM 586220 for complete testing of the C64 and most of the C128.
Download your own copy of the Diagnostic ROM 586220: (c64_diag_rev410.zip)
Mail Call #1 where I first featured the PCBs:
To donate to Adrian's Digital Basement:
Adrian Black - Mail Call
4110 SE Hawthorne Blvd.
Portland, OR 97214-5246