Toggle the GPIO in Jetson Orin Nano Using Jetpack 6.0 (L4T_36_3)

Issue Overview

Users are experiencing difficulties configuring the CAM0_PWDN pin as an output and toggling its state using gpiod commands on the Nvidia Jetson Orin Nano Dev board with Jetpack 6.0 (L4T_36_3). The specific symptoms include:

• The inability to change the pin state as expected, with users reporting that after executing the gpiod commands, the readback value remains at 0, indicating that the pin is not toggling correctly.
• The issue occurs after following the steps outlined in the developer guide and modifying the Pinmux configuration and GPIO device tree source (dtsi) files.
• Users have flashed their configurations onto the Orin Nano but still observe no change in voltage when manually probing the pin.

The frequency of this issue appears to be consistent among users attempting to configure GPIO settings, significantly impacting their ability to utilize the GPIO functionality for their applications.

Possible Causes

Several potential causes could lead to the observed problem:

• Configuration Errors: Incorrect modifications in the Pinmux or dtsi files may prevent proper pin configuration. If the CAM0_PWDN pin is not correctly set as an output, it will not toggle as expected.

• Software Bugs or Conflicts: There may be bugs in Jetpack 6.0 or conflicts with other software components that could disrupt GPIO operations.

• Driver Issues: If the required drivers for GPIO control are not properly installed or configured, this could lead to failure in toggling pin states.

• User Errors: Misconfigurations during the setup process, such as incorrect command usage or failure to set necessary options in gpiod commands, may result in unsuccessful toggling.

• Environmental Factors: Issues like insufficient power supply or overheating could affect GPIO performance, though this is less common.

Troubleshooting Steps, Solutions & Fixes

To address the issue of toggling the CAM0_PWDN pin on the Jetson Orin Nano, follow these detailed troubleshooting steps:

1. Verify Pin Configuration:

   • Ensure that you have correctly modified both the Pinmux and gpio dtsi files. Check for syntax errors or incorrect parameters.
   • Example modifications should include:

     uart4_cts_ph6 {
         nvidia,pins = "uart4_cts_ph6";
         nvidia,function = "rsvd1";
         nvidia,pull = <TEGRA_PIN_PULL_NONE>;
         nvidia,tristate = <TEGRA_PIN_DISABLE>;
         nvidia,enable-input = <TEGRA_PIN_DISABLE>;
         nvidia,io-high-voltage = <TEGRA_PIN_DISABLE>;
         nvidia,lpdr = <TEGRA_PIN_DISABLE>;
     };
     

2. Reflash Configuration:

   • After verifying your configurations, reflash your images using:

     sudo ./flash.sh jetson-orin-nano-devkit mmcblk0p1
     

3. Set Mode Option for gpiod Commands:

   • It is crucial to set the mode option when using gpioset to ensure that changes persist beyond the command execution. Use:

     sudo gpioset -m 0 49=0
     sleep 1
     sudo gpioset -m 0 49=1
     

4. Check Voltage Manually:

   • After executing your commands, manually probe the CAM0_PWDN pin with a multimeter to check for voltage changes.

5. Use gpioget to Verify State:

   • Execute:

     sudo gpioget 0 49
     

   • Ensure that this command returns a value of 1 after toggling.

6. Review Documentation and Updates:

   • Consult Nvidia’s official documentation for any updates regarding GPIO configurations specific to Jetpack 6.0.
   • Look for any firmware updates or patches that may address known issues with GPIO functionality.

7. Seek Community Support:

   • If problems persist after following these steps, consider reaching out on forums or Nvidia’s support channels for additional assistance from other users who may have encountered similar issues.

8. Best Practices:

   • Always back up original configuration files before making changes.
   • Regularly check for software updates that might include bug fixes related to GPIO operations.

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