request - I2c functionality for extra Gpios about gpionext HOT 1 CLOSED

It's a good suggestion, but I probably won't be working on it anytime soon as my day job has me pretty busy at the moment. You can always use combos to simulate having extra pins. For example, pin 3 = 'A', pin 5 = 'B', pin 3+5 = 'C'.

With combos, you can essentially set aside one 'shift' pin for each player to work as follows:

PLAYER 1:
'SHIFT PIN'=37
UP=3
DOWN=5
LEFT=7
RIGHT=11
A=15
B=13
X=19
Y=21
LSHOULDER=29
RSHOULDER=31

START=SHIFT+A (37+15)
SELECT=SHIFT+B (37+13)
COIN=SHIFT+X (37+19)
EXIT=SHIFT+Y (37+21)

PLAYER 2:
'SHIFT PIN'=40
UP=8
DOWN=10
LEFT=12
RIGHT=16
A=18
B=22
X=26
Y=32
LSHOULDER=36
RSHOULDER=38

START=SHIFT+A (40+18)
SELECT=SHIFT+B (40+22)
COIN=SHIFT+X (40+26)
EXIT=SHIFT+Y (40+32)

To use the shift pin technique, you can either wire each shifted button to 2 pins (plus ground pin), or you can wire 1 button to act as your 'shift' button and just require the player to press the 'shift' button + another button at the same time.

from gpionext.