TEOS – A C64 operating system in the making

YouTuber “64jcl” is currently making a character mode, graphical OS for the C64 – and he is showing good progress. I’m personally really impressed by the smooth multitasking exhibited in the last video:

Here’s the entire playlist, where we can follow the progress: TEOS64 - YouTube

(And no, the project is not open source at this stage, but it may become available eventually, when considered finished.)


Wow. That is really impressive. I would have been amazing to have had an OS like that back in the day.

I never ran GEOS with my 64 or 128, but for me this looks better.

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I’ve been following this WIP for the past month or so. It looks great so far, my only gripe being the lack of a wireframe window drag feature.

Does anyone have a sense of the resource / RAM footprint? Is it practical to run on a stock 64?

Regarding wireframe window dragging, I guess, windows may be copied to sprites, which wouldn’t be too demanding on runtime resources. Since this wouldn’t work for (very) large windows, there should be a fallback mode for this. Maybe, there’s also a restriction on window sizes, so that this would work anyway. (Mind that this is just me guessing.)

Regarding memory footprints, the applications shown are not that demanding. However, it does load bitmap images, which are a bit more substantial than these tiny demo apps. (Meaning, 8K for the bitmap, another 1K for the color information, space required for the encoded image (or some equivalent buffer) and some space for the display application. Which would suggest about 16K of free RAM, at least.)

Edit: The biggest application seen in the last video is about 5K and the image files are about 10K on disk.