Pocket Calculator Control Interface

Programmable calculators used to be exotic, but now they are standard equipment in almost every school or polytechnic. The TI-83 (Plus) and TI-84 Plus are especially popular. Both models have a ‘link port’ for exchanging data. If you connect the right hardware to this port, you can do much more with it.
Every technician or engineer has a pocket calculator somewhere on their desk. Although the internal processes of these calculators are hardly suitable for control tasks, some of them can be used to build a nice robot.

Technical specifications
• 32 ESD-protected inputs/outputs including connectivity for I2C, AVR-ISP, JTAG, RS485 and general I/O.
• Supply regulation using 7805
• Firmware all in C
• Simple to program