Plan 9 BCM
cd '#G'/gpio
echo scheme bcm > ctl (... board, wpi)
echo 0 > GPIO0
echo 0 > OK
echo function in GPIO0 > ctl
echo function out GPIO0 > ctl
echo function 1 GPIO0 > ctl (... 2 3 4 5, refer to BCM manual)
echo event edge-rising enable GPIO0 > ctl
echo event edge-rising disable GPIO0 > ctl
echo event edge-falling enable GPIO0 > ctl
echo pull up GPIO0 > ctl
echo pull down GPIO0 > ctl
cat event
cat GPIO0
cpu% echo scheme bcm > ctl
cpu% lc
1 11 15 18 21 23 25 7 9 ctl
10 14 17 2 22 24 4 8 OK event
cpu%
cpu% echo scheme board > ctl
cpu% lc
CE0 GPIO0 GPIO2 GPIO4 GPIO6 MISO OK SCL SDA ctl
CE1 GPIO1 GPIO3 GPIO5 GPIO7 MOSI RxD SCLK TxD event
cpu%
cpu% echo scheme wpi > ctl
cpu% lc
0 10 12 14 16 3 5 7 9 ctl
1 11 13 15 2 4 6 8 OK event
cpu%