With the help of a custom firmware, the Python module is converted into an USB to serial bridge, connected to an ESP8266 module that was added inside the case. The ESP8266 is running a stock MicroPython. The video is showing some interactions with the ESP8266 over WiFi with MicroPython WebREPL, while the module is connected to the calculator. Everything typed on the WebREPL could have been entered directly on the calculator, but typing on a real keyboard if far more easy (at least for me) ! Read more ...

The TI-83 Python module The module was released as an add-on to the calculator to add a Python interpreter. There was a lot of questions about it, and it was found that it is running a custom CircuitPython Dumping the firmware Before discovering the bootloader trick, I dumped pretty easily the firmware, using a BlackMagicProbe and test points TP7 and TP8 on the back of the modules. This correspond to the SWD debug interface (SWDIO on TP7 and SWDCLK on TP8). Read more ...

Disclaim This article is not up to date. It is just a place to document what I have done some time ago regarding this contest on TI-Planet : https://tiplanet.org/forum/viewtopic.php?t=20557 Introduction First, a compatible SPI flash chip must be soldered inside the calculator on the U7 pad. I used an AT25SF641 kindly donated by TI-Planet, as it was the part referenced on the official schematics. At the time, there was no implementation of USB inside the official firmware so I choose to write a small loader compatible with the flashrom serprog protocol. Read more ...