Difference between revisions of "GPIO for NanoPi"

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(Created page with "== GPIO (in/out) for NanoPi == Note: the test environment is a NanoPi K1 Plus with FriendlyCore installed in eMMC, kernel 4.14.x . To enable a pin, execute: echo X > /sys/...")
 
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and the directory/symbolic link gpio9 will disappear.
 
and the directory/symbolic link gpio9 will disappear.
  
To set the
+
To set the direction (input or output pin), we need to execute:
 +
 
 +
echo out > /sys/class/gpio/gpio9/direction
 +
 
 +
or
 +
 
 +
echo in > /sys/class/gpio/gpio9/direction
 +
 
 +
To set the value:
 +
 
 +
echo 0 > /sys/class/gpio/gpio9/value
 +
echo 1 > /sys/class/gpio/gpio9/value
 +
 
 +
To read the value
 +
 
 +
cat /sys/class/gpio/gpio9/value

Revision as of 13:24, 1 March 2020

GPIO (in/out) for NanoPi

Note: the test environment is a NanoPi K1 Plus with FriendlyCore installed in eMMC, kernel 4.14.x .

To enable a pin, execute:

echo X > /sys/class/gpio/export

where X is the number of the linux gpio corresponding to the pin you want to enable.

For example, if we want to enable pin N. 37, according to the table in http://wiki.friendlyarm.com/wiki/index.php/NanoPi_K1_Plus#Diagram.2C_Layout_and_Dimension , we need to execute:

echo 9 > /sys/class/gpio/export

A new /sys/class/gpio/gpio9 directory will appear.

In the same way, to disable the pin we need to execute:

echo 9 > /sys/class/gpio/unexport

and the directory/symbolic link gpio9 will disappear.

To set the direction (input or output pin), we need to execute:

echo out > /sys/class/gpio/gpio9/direction

or

echo in > /sys/class/gpio/gpio9/direction

To set the value:

echo 0 > /sys/class/gpio/gpio9/value
echo 1 > /sys/class/gpio/gpio9/value

To read the value

cat /sys/class/gpio/gpio9/value