GPIO 492 Invalid Argument Error on Nvidia Jetson Orin Nano Dev Board

Issue Overview

Users of the Nvidia Jetson Orin Nano Dev Board are experiencing difficulties when attempting to set GPIO pin PAC.06 (identified as GPIO number 492) to a high state using the gpiod library commands. The issue arises after successfully booting the device with a custom carrier board, where users report the following symptoms:

• Error Messages: Users encounter the error "gpioset: error setting the GPIO line values: Invalid argument" when trying to execute commands to set GPIO 492 high.

• Context of Occurrence: This issue occurs during attempts to manipulate GPIO pins after booting the system and while using commands like gpioset and gpioget.

• Hardware and Software Specifications: The discussions reference a custom carrier board and mention modifications to pinmux settings. The software environment includes the Nvidia Jetson Linux version R36.2.

• Frequency of Issue: Multiple users have reported similar problems, indicating a consistent issue within this context.

• Impact on User Experience: The inability to control GPIO pins as expected hampers development and testing of applications that rely on GPIO outputs, thus affecting overall functionality.

Possible Causes

Several potential causes for the observed issue have been identified:

• Default Pin Configuration: PAC.06 is configured as an input pin by default, which prevents it from being set as an output without appropriate modifications in the pinmux settings.

• Incorrect Command Usage: Users initially attempted to use GPIO number 492 instead of the correct line number (144) in their commands, leading to confusion and errors.

• Pinmux Configuration Errors: If the pinmux settings are not correctly modified and applied, the desired output behavior cannot be achieved.

• Driver or Software Bugs: There may be underlying bugs in the gpiod library or conflicts with other software components that affect GPIO functionality.

• Environmental Factors: Issues such as power supply inconsistencies or overheating could potentially affect GPIO operations, although this has not been explicitly mentioned in user reports.

Troubleshooting Steps, Solutions & Fixes

To resolve the issue with GPIO 492 on the Nvidia Jetson Orin Nano Dev Board, users can follow these troubleshooting steps:

1. Verify Pin Configuration:

   • Check if PAC.06 is set as an input pin by default.
   • Modify the pinmux spreadsheet to configure PAC.06 as an output pin. Refer to the Nvidia documentation for guidance on generating pinmux .dtsi files.

2. Use Correct Command Syntax:

   • Use the following command to set GPIO line 144 high after ensuring that it has been configured as an output:

     sudo gpioset --mode=wait 0 144=1
     

   • Avoid using GPIO number 492 directly; instead, always use line numbers after confirming their mappings.

3. Check Pin State with Multimeter:

   • After executing gpioset, measure the voltage on PAC.06 with a multimeter to confirm if it is set high.

4. Flashing Modifications:

   • If changes were made to the pinmux file, re-flash only necessary components without re-flashing the entire root filesystem:

     sudo ./flash.sh --no-systemimg -c bootloader/generic/cfg/flash_t234_qspi.xml jetson-orin-nano-devkit internal
     

   • This command will apply changes faster than a full re-flash.

5. Resolve Flashing Errors:

   • If errors occur during flashing, ensure that the board is in force recovery mode and recognized by your host computer (check with lsusb).
   • Address specific error messages like "Unrecognized module SKU" by verifying board connections and configurations.

6. Investigate Naming Conventions:

   • Ensure that any .dtsi files generated follow proper naming conventions as outlined in Nvidia’s documentation.
   • Use the correct template file for generating pinmux configurations, such as Jetson_Orin_NX_series_and_Orin_Nano_series_Pinmux_Config_Template.xlsm.

7. Test Incrementally:

   • When making multiple changes, test one GPIO pin at a time to isolate any issues that arise during flashing or configuration adjustments.

By following these steps, users should be able to troubleshoot and resolve issues related to setting GPIO pins on their Nvidia Jetson Orin Nano Dev Board effectively.