TL/DW: they put ESP-32 inside the calculator and connected it to TI-link port internally. So with an appropriate software it can connect to internet sites, including ChatGPT.
Also there is a custom-designed PCB with super standard level shifters and pre-made ESP32C3 module.
Git repo: https://github.com/chromalock/TI-32/
I'm afraid the calculator with the code is long dead - but really was a very simple (and very slow) straightforward renderer in whatever the horrible Casio basic programming language was called.
As I recall I first implemented a simple zirpenzky gasket - and then wrote a renderer for the Mandelbrot set. Took only about 5 to 8 hours runtime to do a black and white Mandelbrot...
I was reading a brilliant book at the time, which I've since donated to a school library (and i fear they in turn threw it away) - can't find the exact book now, I think maybe it was called "A walk through modern mathematics" or something like that. Came out in the 90s and had a bit about various chaos theory stuff in it.
Thank you. Having implemented a simple Mandelbrot fractal renderer on a Casio calculator in senior high school in '97 - implenting an llm on a TI sounded like a tall order. Cool hack, though!