Pin number

AGX Xavier GPIO name

AGX Xavier GPIO number

AGX Orin GPIOname

AGX Orin GPIOnumber

GPIO usage

This guide covers the Linux interface for GPIO operations using bash

Available GPIO's

The following output provides a list of all GPIO's that are available to the Jetson. This includes Tegra GPIO's as well as external driven GPIO extender.

If you want to do this Linux interface on a external connected GPIO extender, requires changes to the DeviceTree. A more detailed Instruction on how to implement such a device can be found in the Linux kernel Documentation.

Syntax: sudo cat /sys/kernel/debug/gpio

Debug gpio output

test@test-desktop:~$ sudo cat /sys/kernel/debug/gpio
[sudo] password for test: 
gpiochip1: GPIOs 316-347, parent: platform/c2f0000.gpio, tegra234-gpio-aon:
 gpio-316 (PAA.00              )
 gpio-317 (PAA.01              )
 gpio-318 (PAA.02              )
 gpio-319 (PAA.03              )
 gpio-320 (PAA.04              )
 gpio-321 (PAA.05              |fixed-regulators:reg) out hi 
 gpio-322 (PAA.06              )
 gpio-323 (PAA.07              )
 gpio-324 (PBB.00              )
 gpio-325 (PBB.01              )
 gpio-326 (PBB.02              )
 gpio-327 (PBB.03              )
 gpio-328 (PCC.00              )
 gpio-329 (PCC.01              )
 gpio-330 (PCC.02              )
 gpio-331 (PCC.03              |mux                 ) out hi 
 gpio-332 (PCC.04              )
 gpio-333 (PCC.05              )
 gpio-334 (PCC.06              )
 gpio-335 (PCC.07              )
 gpio-336 (PDD.00              )
 gpio-337 (PDD.01              )
 gpio-338 (PDD.02              )
 gpio-339 (PEE.00              )
 gpio-340 (PEE.01              )
 gpio-341 (PEE.02              )
 gpio-342 (PEE.03              )
 gpio-343 (PEE.04              |power-key           ) in  hi IRQ ACTIVE LOW
 gpio-344 (PEE.05              )
 gpio-345 (PEE.06              )
 gpio-346 (PEE.07              )
 gpio-347 (PGG.00              )
gpiochip0: GPIOs 348-511, parent: platform/2200000.gpio, tegra234-gpio:
 gpio-348 (PA.00               |fixed-regulators:reg) out lo 
 gpio-349 (PA.01               )
 gpio-350 (PA.02               )
 gpio-351 (PA.03               )
# And so on...

The GPIO numbers listed in the Linux operating system do not match with the numbers of the Jetson socket pins.

Export GPIO

At first, you have to export the GPIO that you want to use in the Linux file system in order to configure and read or write data from it.

Syntax: echo <GPIO_NR> > /sys/class/gpio/export

export gpio

nvidia@nvidia-desktop:~$ echo 414 > /sys/class/gpio/export
nvidia@nvidia-desktop:~$

Change GPIO direction

The GPIO direction decides if the GPIO should be used as Input or Output

Keep in mind that some Carrierboards are using unidirectional level shifters -> In this case only one direction will work properly.

More Information about such implementations are documented in the corresponding manual of your Carrierboard.

Syntax

change direction

echo <in|out> > /sys/class/gpio/gpio<GPIO_NR>/direction

Change direction

echo <in|out> > /sys/class/gpio/gpio<GPIO_NAME>/direction

Change direction

echo <in|out> > /sys/class/gpio/gpio<GPIO_NR>/direction

Configure as Input

set GPIO direction as input

nvidia@nvidia-desktop:~$ echo in > /sys/class/gpio/gpio414/direction
nvidia@nvidia-desktop:~$

Configure as Output

set GPIO direction as output

nvidia@nvidia-desktop:~$ echo out > /sys/class/gpio/gpio414/direction
nvidia@nvidia-desktop:~$

Set GPIO Value

The logical GPIO level can be configure in the following ways. Keep in mind that its required to configure the GPIO as output before changing its output value.

Syntax

change direction

echo <0|1> > /sys/class/gpio/gpio<GPIO_NR>/value

Change direction

echo <0|1> > /sys/class/gpio/gpio<GPIO_NAME>/value

Change direction

echo <0|1> > /sys/class/gpio/gpio<GPIO_NR>/value

Set low

Set output as logical low

nvidia@nvidia-desktop:~$ echo 0 > /sys/class/gpio/gpio414/value
nvidia@nvidia-desktop:~$

Set high

Set output as logical high

nvidia@nvidia-desktop:~$ echo 1 > /sys/class/gpio/gpio414/value
nvidia@nvidia-desktop:~$

Read GPIO state

Syntax

change direction

cat /sys/class/gpio/gpio<GPIO_NR>/value

Change direction

cat /sys/class/gpio/gpio<GPIO_NAME>/value

Change direction

cat /sys/class/gpio/gpio<GPIO_NR>/value

The following example reads the current state of the GPIO. This operation works in output as well as in input mode.

read GPIO state

nvidia@nvidia-desktop:~$ cat /sys/class/gpio/gpio414/value
0
nvidia@nvidia-desktop:~$ cat /sys/class/gpio/gpio414/value
1

GPIO Mappings

Sadly it is not trivial to get the correct GPIO numbers that easy, this is why we try to provide a full list of GPIO Mappings on the following pages.

As new compute modules are released, new GPIO Mapping tables are needed and sometimes software updates also can change this mapping (we saw some problems with Jetpack 5.0).

The following chapter on how to calculate GPIOs is provided if you encounter any problems with our GPIO mapping tables

How to calculate GPIOs

Pleas first check if your compute module is included in the provided tables

The above list should include every GPIO mapping there is. This “how to” may help you find errors we did in our documentation or to calculate GPIOs for upcoming compute modules or software changes.

GPIOnumber

The basic formula:

GPIOnumber = GPIOletter *8 + GPIOdigit + GPIOoffset

GPIOletter

The GPIOletter is located between [GPIO3_P] and [.digit]

GPIOname

GPIOletter

GPIOletter (referenced)

This letter needs to be referenced to a number.

This number is individual to every Jetson module and can be found in the “tegra-gpio.h” (name may differ depending on module).

The Table is included at the end of this guide.

GPIOdigit

The GPIOdigit is easiest to get and can be extracted directly from the name.

GPIO3_PO.[GPIOdigit]

GPIOoffset

The Jetson module has 2 GPIO-Chips with a given offset. Each Chip provides a specific amount of GPIO's that are divided into several segments. The segments are differentiated by using letters.

Example

Calculating GPIO number GPIO3_PK.04 for Jetson AGX Xavier:

GPIOnumber = GPIOletter *8 + GPIOdigit + GPIOoffset
GPIOnumber =    10      *8 +     4     +   288       = 372   #GPIO3_PK.04 on AGX Xavier

Table

These tables are extracted from the “tegra-gpio.h” file for the specific module:

Need to be checked as it is not completely verified

GPIO - Guide

Guide

AGX-Xavier / AGX-Xavier-Industrial / AGX-Orin

AGX-Xavier / AGX-Xavier-Industrial / AGX-Orin

GPIO usage

Available GPIO's

Export GPIO

Change GPIO direction

Syntax

Configure as Input

Configure as Output

Set GPIO Value

Syntax

Set low

Set high

Read GPIO state

Syntax

Nano / TX2-NX / Xavier-NX

GPIO Mappings

How to calculate GPIOs

GPIOnumber

GPIOletter

GPIOdigit

GPIOoffset

Example

Table

TX1 / TX2 / TX2i

Overview

Document revisions and changes

What are GPIO's?