I have a naive keyboard matrix (no diodes, so only 2 simultaneous key presses can detected, at most).
I would like to read this matrix by connecting the columns to GPIO pins configured as outputs and the rows to GPIO pins configured as inputs.
By driving the column pins, one at a time, it should be possible to test which keys are pressed by reading the GPIO input pins.
(I will run a polling daemon, written in C, to read the matrix, and squirt data into the kernel using the uinput kernel driver.)
Will I fry the RPi by connecting GPIO-outs to GPIO-ins?
(If GPIO inputs act as near infinite resistances, then there will be no problem - but I don't know this.)