i75 keyboard. 9x9 matrix.
Multiple controller options. Arduino Pro Micro, Teensy 2.0, TeensyLC/3.2
Pinout
Cols B5 B6 B2 B3 B1 F7 F6 F5 F4 Rows B4 E6 D7 C6 D4 D0 D1 D2 D3