Topic: How to: FIND and TEST GPIOs
I found it really hard to discover if my GPIO numbers were correct while making a profile for my device. Eventually i was able to test and confirm my switches using the following method:
on the devices command line (i used the serial console of my device):
cd /sys/class/gpio/ echo 10 > export cd gpio10 cat value
this should make it possible to read a one or zero on GPIO number 10 on the device, repeat the final command (cat value) while holding button in or releasing. For other GPIOs substitute numbers accordingly, and to display leds you may be able to modify the value with:
echo 0 > value echo 1 > value
the above would toggle the GPIO output.
I'm not sure if the direction register for GPIOs are modified by these commands, if the direction register on an input can be changed to output then it is possible to damage the chip(this depends on the manufacture of each device).
I systematically checked each one as above, if there is an easier way lets hear it!
furthermore after i tested each one i did:
echo 10 > unexport