I am trying to connect the TX2 to another device via the GPIO. From another thread I was able to figure out that the GPIO numbers on the J21 are as follows:-
Pin 37 (GPIO8_ALS_PROX_INT) is GPIO 388
Pin 33 (GPIO11_AP_WAKE_BT) is GPIO 389
I used Pin 33 for this experiment and used the following commands on Linux to export the GPIO to user space
echo 389 > export
echo in > gpio389/direction
I see that the value is set to 1 right now. I am now toggling the GPIO from the other device which I also verified on the oscilloscope. But the value always remains 1 and does not change.
Is there anything I am missing?