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Veronica – F18A Address Decoding
Bridging The Gap As you probably know if you’re the kind of person who follows this blog, the 6502 CPU (the 1970s chip around which Veronica is based) talks to the outside world entirely via memory...
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Veronica – F18A Control Signals
It was the best of times, it was the worst of times. With our recent success in remembering how to do address decoding, it was time to look at the control signals. The V9918A has three basic ones-...
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Elliptical – Rear Subframe Replacement
Testing the limits of my desire to repair. What’s this? Is that my elliptical machine on the operating table again? How can this be? The previous repair seemed quite final. Well, I was doing my daily...
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Veronica – Transceiver Repair
Do not go gentle into that good night. Just when things were starting to go really well on the Put An F18A In Veronica plan, well, I fried an irreplaceable device. Yes, if you’re following along, you...
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Veronica – Transceiver Strikes Back
THIS IS FINE. After the incredible success of our last bit of work on Veronica’s F18A, I was very excited to get started on the software to talk to this thing. My ultimate goal is to have the F18A...
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Veronica – F18A Baby Steps
One step back, two steps forward. If you’ve been following this Put-An-F18A-In-Veronica drama, you know that we had some very light early successes, followed by an emotional rollercoaster of tragic...
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Veronica – F18A Font
Shuffling bits for fun and profit(?) Last time, we got the F18A physically repaired and running off Veronica’s power supply. Things seemed to be working okay, and I could copy bytes into registers,...
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Johnny – CPU Board Repair
The cost of procrastination. If you’re a regular reader of this blog, one thing you know is that I’ve been having chronic problems with the Start button on my 1995 Williams’ pinball machine, Johnny...
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Mockingboard 4c+
Because Interrupts Are Hard. The Apple II was (well, still is) a computer devoid of interrupts. I think most modern software engineers probably under-appreciate the implications of that. Folks skilled...
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Reversing Choplifter
Because it seemed like a good idea at the time. The Apple II line of computers had an amazing run, from 1977 to 1993. In that time, hundreds of thousands of pieces of software were written for it,...
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