1) The CD4000 series is about the slowest logic family that's still on the market. Switching to anything else - 74LS, 74HC, take your pick - will improve your fMax dramatically.
2) Every IC on your board needs a decoupling capacitor as close to its power/ground pins as possible. Not having those is probably causing a lot of weird behavior, including the "interference" you're seeing from other devices.
Great work. I miss the speed we had before graphics card were a thing. Everything was literally 100x faster to render. I wish we could bypass graphics card entirely on modern Oses and computers but it looks like it’s not even possible anymore with EUFI. I would buy a card that works for TUI only, and with a large set of Unicode chars, and works on a 6K screen.
Text mode actually needed a GPU to be fast, it just wasn't called that back in the day. It was dog slow on older hardware to render text in software, even from bitmaps.
Right, I think they were more just like "VGA cards" or "graphics adapters" for a while, and before that would have been CGA/EGA/Hercules, etc. I view the first GPUs as being those with 2D + 3D acceleration.
50x18 chars... well, I've seen a patched Nethack for the Zipit Z2 (altough you can perfectly set a micro-font being able to fit a whole standard 80x24/25 char screen).
We could tie it to an error signal from the OS or prompt, so that if `$?` is non-zero then the magic smoke is released. This would encourage careful programming.
This is very cool! I like the idea of a real text-mode card for a homebuilt PC versus the more framebuffer-like card that Ben designed. Nice work. I also like the natural progression from text to Pikachu. :D
1) The CD4000 series is about the slowest logic family that's still on the market. Switching to anything else - 74LS, 74HC, take your pick - will improve your fMax dramatically.
2) Every IC on your board needs a decoupling capacitor as close to its power/ground pins as possible. Not having those is probably causing a lot of weird behavior, including the "interference" you're seeing from other devices.