Hello,
I try to access the GPIO pins thorugh /sys/class/gpio to write values to them. Later, I want to construct a C++ program for that, but for now I try by hand through the console. Here are, for example, my commands to output a HIGH on pin 19:
$ sudo su
# echo "16" > /sys/class/gpio/export
# echo "out" > /sys/class/gpio/gpio16/direction
# echo "1" >/sys/class/gpio/ gpio16/value
I followed a simple Raspberry Pi tutorial for this and hoped this would work since the GPIO structure is pretty much the same as by Jetson Nano, but it doesn’t. I measured with an oscilloscope and there’s no voltage at all on the pin, despite the fact that no error messages are given. I tried different pin numberings, too, but the sysfs gpio numbering should theoretically be correct.
What am I doing wrong? Can you even do it that way? Can someone link me a proper pinout diagram for Jetson Nano (because I found none)?
EDIT: I looked at the status of the GPIO pins during the above process with $ cat /sys/kernel/debug/gpio, and it really states that HIGH is outputted at pin 16, but again, measuring with oscilloscope confirms there is no actual current flowing. Where could the problem lie then?