C16 Repair Part 2

The marginal C16, with a stolen 8501 Processor hiding it gets new life.

First things first, I had to get this thing running again. I wasn’t going to be able to live with swapping the CPU between this and the Plus/4. But the 8501 processor is fairly rare, and not particularly well made. But thanks to some creative mind, there is a 6510 to 8501 adaptor board! This will let me use a 6510 (from the C64) in the machine with a modified Kernal ROM and losing access to one feature.

The process is effectively Plug and Play (weird to say about a Commodore computer, right?) and the computer won’t know the difference. Well, as long as you never use the tape functions again, and I won’t be.
But the socket on a board in a socket stack was a bit too tall to put the RF/heat shield back in place, so I soldered the adaptor board straight to the mainboard for clearance. I’m never taking this back to a 8501 again, so that seems like it works.

The 264Diag ROM doesn’t like the modified KERNAL ROM, which makes sense, the checksum won’t work. But everything else seems to be fine.

Now, for that marginal video…. it’s never been good, but it could be a lot better. We’ll get there.