from a comment posted on Hackaday in the Review: Single Board 65C02 and 65C816 Computers topic:

http://atari8.co.uk/gui/






It may seem like a waste of time to try something like this now in 2015. But although I have not had any exposure to 6502 Atari computers, what fascinates me is the discipline and care used to pull this off in a system with such limited memory and execution speed. It's definitely a good practice, and forces one to be more efficient with the resources. It's a valuable skill to transfer to any system, including ones where bloatware and programming sloppiness are the norm. Our son's phone crashed today, and took several minutes to re-boot. Why did it crash? Bugs. Why did it take so long to re-boot? Bloat.

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Interesting. I owned an Atari 400 and later an 800 XL back in the 80s and really liked them. They were seriously underrated compared to the Apple II, and it wasn't until the C64 that another computer matched the ability of their custom graphics and sound ICs. Wish I never sold them.

If anyone wants to employ me to develop embedded systems, I also know C. (I'm the author of the GUI).

Here's a very impressive update video:
https://www.youtube.com/watch?v=T14dL9M ... e=youtu.be
He has up to eight windows up at once (if I counted right), and moves them around very quickly with the mouse, and you can see that the ones not selected are still doing their jobs and updating a graph. Edit: He told me later that it's not limited to eight.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

I liked the RAM numbers: 1KB used, 1KB free.. you don't see that very often for a windowed GUI. My 4GB notebook with swap runs out all the time.

It apparently has a megabyte of RAM, banked. The memory counts are in KB, and it looks like the demo uses about a tenth of the total RAM. Jon writes, "The Atari commonly banks memory in 16KB banks in a window at $4000-$7FFF. Almost all extended RAM upgrades bank this memory using bits of PORTB ($D301) which used to be the joystick 3 and 4 port on the 800 before they were dropped in the XE line."

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

This is a ridiculously amazing piece of work. The smoothness of the GUI is notable - apart from 1MB RAM is the rest of the machine standard (e.g. 1.79MHz 6502)?

Excellent coding, my hat goes off to some super software engineering!

This is amazing. This kind of optimization is a lost art these days. We have web applications that blindly sling 2+MB all over the place and no one seems to care. Until everything runs like molasses.

I wonder how it would work on a stock 800XL? Or 130XL?

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Cat; the other white meat.

Huh, I've been actually doing a lot of backburner design work on finishing this relic from the past. 1999, when LUnix was still kind of a thing:



Might have to get back to it for real, even if just for competitiveness' sake. But on 1MHz/64KB of course, none of this bigger/faster nonsense.

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WFDis Interactive 6502 Disassembler
AcheronVM: A Reconfigurable 16-bit Virtual CPU for the 6502 Microprocessor

Yes: standard 6502C at 1.77MHz (PAL), emulated in the latest video.



Thanks!



Stock 800XL would be a tight squeeze unless an application, all drivers, fonts, and desktop can be stored in the same (base) 16KB bank of RAM. It's unlikely. A 130XE is perfectly adequate, however. The extra 64KB is ample to house fonts, drivers, and several concurrent processes.

Thanks for the comments!