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Comment by z2 | Hacker News Reader

Immediately thought of the assembly-level hacking people did ~20 years ago on TI's graphing calculators to get reliable grayscale, for instance this on the TI 83 series: https://www.ticalc.org/archives/news/articles/7/77/77966.htm...

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Haha, thanks for dredging this up, I made that :) It seems quite related to the OP article. It's a library for making grayscale games on the TI83 graphical calculator, which has a monochrome display. The main challenge was optimizing the interrupt routine, the z80 assembly code that performed the flickering/dithering that achieves the grayscale effect, to fit within the tiny amount of clock cycles available on the Zilog Z80 6 MHz processor. Even after optimization, it took up ~50%-75% of all available cycles. Some people managed to make some pretty fun grayscale games with it (e.g. https://www.ticalc.org/archives/files/fileinfo/331/33153.htm...). This was obviously in the pre-smartphone era, so the ti83 was quite popular for playing games in class, and hand written assembly code was the only way to make it fast.

I knew immediately that the link was to Desolate before opening it :) It blew me away the first time I played it, as I was used to my shitty turn-based TI-BASIC games.

Cool to see that one of the authors of the most cited paper in machine learning also got their start hacking on TI calculators. What a great learning environment that was!

Holy crap! This takes me back. I used this (or something based on it) on my TI84 SE+ to play around with grayscale over a decade ago. It's the first thing that came to mind when I saw this article. I never got into ASM on the TI calcs but I wrote a TON of TI-Basic. I spent a ton of time on those forums and posted a number of apps/games I wrote (though I can't find them now).

Not that anyone hadn't thought of it before, but I believe that I may hold the first claim of a grayscale TI calculator demo. I released a four-frame, 4-bit grayscale animation of beavis & butthead headbanging for the newly minted Zshell on TI-85 in 1992. I posted it to one of the listserves or usenet groups, but I have never been able to find a copy in anyone's archives. I'd love to see it again. It was not a fancy program. The frames were stored as 4 x 4 x 64x128 bitmaps = 16KB so it consumed like 2/3 of the calculator's memory. Fun times.

If anyone is a usenet archive ninja, my program was called 'BBANIM' and there was a TI-basic POC and zshell asm version released.

I recall that the first game using PoV grayscale was "Plain Jump" (sic) shortly afterwards which apparently continues to be a popular project to clone.

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