Remote Controlling a TI-84+ from a PC

There is a remote control protocol baked into TI 84+ graphing calculators so that it is possible for Texas Instruments to make products that take control of calculators in the classroom via their link ports. I implemented the protocol on an Arduino and made a control program in Ruby to draw arbitrary black and white images on the calculator's screen with its built in pen drawing tool (which is meant to allow graphs to be annotated). Because there is a limit to the rate at which keys can be pressed I implemented a simple flood-fill algorithm for efficiently finding an efficient sequence of keypresses to draw a given image.

Reviving the old work

Code

https://github.com/jmptable/calc_control