Teensy 3.1 sketch to translate usb keyboard to TI-99/4a 15 pin interface.
This project interfaces a Teensy 3.1 and a Circuits@Home USB Host shield, to take input from a USB keyboard, and simulate the matrix keyboard built into the TI.
The USB keyboard can be used with the TI keyboard still in place. The user can switch between them at will.
TIUSBKeys.rrb - PCBoard layout from Robot Room Copper Connection Studio Edition v3.0
gerber - folder containing necessary gerber images and drill files for printing pcboard
TIUSBKeys.sch - PCBExpress schematic source file
schematic.pdf - schematic exported to PDF
TI99USBKeys - folder containing arduino project files for Teensy 3.x