65816: 32-bit Floating-point Package Available

I wrote in my previous post about testing my 32-bit floating-point package on a Mandelbrot plot. Paying forward Marco’s original 128-bit package contribution, I’ve made my 32-bit package available on my GitHub. It’s still a work in progress with limited functionality. But it’s still enough to handle Mandelbrot which was my original goal. Function Stack …

65816: Floating Point – Finding a Balance Between Speed and Precision

I first got interested in the 65816 because of floating=point support. I had just finished porting Cosmic Conquest, an old text-based strategy game, to my 6502 system and was looking for other old games to port. I remembered an old text-based Star Trek game but on tracking it down discovered that it used floating point. …

65816: Build 4 – Current Status – 7/15/2022

Build 4 – Current Specification As of 7/15/2022, Build 4 has tested successfully with: Both 65C02 and 65C816 up to 10 MHz where I started to get display glitches 524k memory. Current configuration: ~457k RAM ($0000-$F7FF, $20000-$7FFFF), 55 ns ~67k ROM ($F800-$1FEFF), 70 ns 256 bytes I/O ($1FF00-$1FFFF) 65C22 VIA ($1FF10, shift register dedicated to …

65816: Build 4 – Troubleshooting 4 – Testing a Different Address Decoder

Off and on throughout my Build 4 troubleshooting journey I kept wondering if the PLD was the underlying issue. While a PLD is handy for making after the fact changes to your build’s memory map, it also has a handy feature I hadn’t thought of before. Since the PLD brings control input and output signals …

65816: Build 4 Troubleshooting 1 – It’s the PLD, or is it?

I worked on the Build 4 modifications over several weeks, partly because I was just playing around with what I had on hand when I started and partly getting sidetracked looking into why things happen instead of just getting on with the build. In this post I discuss one of those side investigations regarding the …