I want to join 2 sparkfun button/led matrix boards so that it is a 4x8 system rather than 2x (4x4) - saving me 8 pins (4 from the buttons, 4 from the LEDs)
I am just wondering, is there any preferred method of doing this - ie: should I be going for 8 in, 4 out or 4 in, 8 out? (or does it not make any difference?)
8 in, 4 out would be easier from my perspective, because I would only need 4 resistors running to ground for the button in lines instead of 8.
help appreciated, thanks!