It's a fairly simple build, but the microcontroller package is quite small and can be difficult to solder.
Before putting one of these anywhere near a PET, I want to make sure that all the pins are connected, and there are no shorts etc.
testing the first ones, I used a signal generator and logic analyser, but that's not really practical to setup each time I built a batch.
avrdude -v -pattiny45 -cusbtiny -eWith the clock sorted, I needed to add some way to test the output, lets face it, it was always going to be flashing LEDs. I had some 20 way LED bar modules I use for the IEEE-488 diagnostics board, so I used a couple of those. Nice and simple one LED per pin, LED on if the pin is high.
-U lfuse:w:0x22:m -U hfuse:w:0xdf:m -U efuse:w:0xff:m
If you would like one of the 6502 diagnostics boards (not the LED tester board!) with PET diagnostics software, you can order one below.
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