Manawyrm | Sarah1d ago

Just released my first ever demoscene demo at Revision 2026 in the Wild-Compo:
A tech demo for Casio fx-9860G graphical calculators!

Sourcecode: https://github.com/Manawyrm/Casiomania

Details: https://kittenlabs.de/casiomania/

https://youtu.be/aLiuF9k3Xt4?t=31

#revision2026

GitHub - Manawyrm/Casiomania: Demo for Casio fx-9860G graphical calculators (audio, grayscale, 3d rendering)

Demo for Casio fx-9860G graphical calculators (audio, grayscale, 3d rendering) - Manawyrm/Casiomania

GitHub
Show threadRonflaix9h ago
@manawyrm glad to see that there are still people pumping out wonders on these calculators.
Show threadRonflaix
@manawyrm so music is doable on the serial port? I haven't looked at the source (well I stopped after recognizing the fxsdk's structure) but I suppose it's something you did through timers, isn't it? Also, DMA? How so? Are you mixing on CPU and just pushing the data through serial with the DMA?
7:53amWeb
Show threadManawyrm | Sarah8h ago

@Ronflaix no timers (those are used for grayscale!) but DMA yes.

Every time the DMA finishes sending bits, it triggers an interrupt which will then generate a new PCM buffer and also convert that into the PWM bitstream.

No mixing at all, just single stream, but you could totally mix if you wanted too.

Show threadRonflaix8h ago
@manawyrm ooh, I didn't know you could wire an interrupt this way, neat! I'm really piss poor at optimizing for SH4 (the pipeline timings wring my brain like nobody's business) but hearing about it kinda makes me wanting for more haha
Show threadRonflaix8h ago
@manawyrm that's pretty good nonetheless! Can we say you made a port audio system (pun intended)? :D
Show threadRonflaix8h ago
@manawyrm by the way, can I ask you how much such a audio subsystem takes on the CPU? It's for a friend's project!
Show threadManawyrm | Sarah8h ago
@Ronflaix I didn‘t even optimize at all basically, it‘s all written in C (altough I had to be a bit careful in certain places like those interrupt routines)