Xavier NX control GPIO

[VastStar]

How can I use Xavier NX’s GPIO using APIS. For instance, what’s the header file I need to include?

[VastStar]

When I use the function named gpioSetDirection, it shows that “Permission denied”.

[JerryChang]

hello VastStar ,

please try below method to access GPIOs.
for example,
Generate gpio220 name under the path of GPIOs
echo 220 > /sys/class/gpio/export
Enable the pin for usage.
echo out > direction && echo 1 > value

[VastStar]

Thanks for your reply.
However, It shows Permission denied, when use command “echo out > direction && echo 1 > value”

bash: direction: Permission denied

[VastStar]

What troubles me is that I don’t kown how to give it permission.

[JerryChang]

hello VastStar ,

did you grant root permission for running this?

[VastStar]

nvidia@nx-jp440:/sys/class/gpio$ echo 417 > /sys/class/gpio/export 
nvidia@nx-jp440:/sys/class/gpio$ echo out >direction && echo 1 > value
bash: direction: Permission denied
nvidia@nx-jp440:/sys/class/gpio$ su
Password: 
root@nx-jp440:/sys/class/gpio# echo out > direction
bash: direction: Permission denied

I don’t kown whether is correct or not.

[ozguryildiz]

Hi @VastStar ,

Have you tried like below?

sudo echo 417 > /sys/class/gpio/export
sudo echo out > direction && sudo echo 1 > value

Regards

[VastStar]

I have tried but got the same result.

[ozguryildiz]

Can you type below command?

sudo chmod +x /sys/class/gpio/gpio417/direction
sudo chmod +x /sys/class/gpio/gpio417/value

[VastStar]

It works. But 22Pin(gpio417) has no output.

[robertogs2]

Hello @VastStar

If you don’t want to change permissions or anything you can use the following commands:

sudo sh -c "echo 417 > /sys/class/gpio/export"
sudo sh -c "echo out > /sys/class/gpio/gpio417/direction"
sudo sh -c "echo 0 > /sys/class/gpio/gpio417/value"

This will run the command that you specify after the -c flag in a new shell with super user permissions and execute it. Maybe you can check with that too and see if the issue is still there.

Regards