Tonight, I got my multimeter and tested my prototype. Surprisingly, I couldn’t find any hardware faults, leaving only software as the culprit. Of course, this confused me, as the exact program had worked on my PCB V1.1.

So, as a quick test, I wrote a little assembly software that would just send back whatever you typed over serial. After plugging the board in and typing a few characters, I found that it worked flawlessly! In my mind, this is a success: it shows that software, although simple, does run as I would expect it to while interfacing with the DART.

Finding this program working, my next step is to flash BASIC to the ROM chip and try to load it again. If it doesn’t work, I’ll have quite a bit of work to do.

I’ll likely have an update tomorrow.