GPIO01 Configuration and Default State on Nvidia Jetson Orin Nano Dev Board

Issue Overview

Users of the Nvidia Jetson Orin Nano Dev board are experiencing difficulties in configuring GPIO01 to have a low default state upon power-up. The specific concerns include:

• Changing the default state of GPIO01 from high to low at power-up
• Modifying GPIO configurations without using the /opt/nvidia/jetson-io/jetson-io.py script
• Uncertainty about which files to modify for achieving the desired GPIO behavior
• Challenges in using the recommended Excel macro for pinmux configuration

The issue impacts the initial state of the GPIO pins and the overall setup process for projects requiring specific GPIO configurations.

Possible Causes

1. Default Pinmux Configuration: The factory default pinmux settings may set GPIO01 to a high state on power-up.

2. Incorrect Device Tree Modification: Attempting to modify the device tree directly without proper understanding of the required changes could lead to misconfiguration.

3. Incompatible Configuration Method: Using /opt/nvidia/jetson-io/jetson-io.py might not provide the granular control needed for specific GPIO states.

4. Software Version Mismatch: The available documentation or tools may not align with the specific Jetson Orin Nano Dev board version being used.

5. Limited Access to Required Tools: Inability to use the recommended Excel macro for pinmux configuration due to software or operating system limitations.

Troubleshooting Steps, Solutions & Fixes

1. Use Official Pinmux Configuration Method:

   • The recommended approach is to modify the pinmux configuration, not the device tree directly.
   • Access the official Nvidia documentation for Jetson Orin Nx/Nano Series at: https://docs.nvidia.com/jetson/archives/r36.3/DeveloperGuide/HR/JetsonModuleAdaptationAndBringUp/JetsonOrinNxNanoSeries.html#mb1-configuration-changes.

2. Modify Pinmux Configuration File:

   • Locate the appropriate pinmux configuration file for your Jetson Orin Nano Dev board.
   • Edit this file to set GPIO01 to a low state by default.
   • Ensure you’re modifying the correct pin definition for GPIO01.

3. Excel Macro Alternative:

   • If unable to use the Excel macro on Windows, consider the following alternatives:
     a. Use a virtual machine with Windows to run the Excel macro.
     b. Collaborate with someone who has access to Windows and Excel to generate the required configuration.
     c. Manually edit the pinmux configuration file, carefully following the format and syntax used in the existing file.

4. Manual Pinmux Editing:

   • If manually editing, locate the section for GPIO01 in the pinmux file.
   • Change the default state to low by modifying the relevant parameters.
   • Example (syntax may vary):

     GPIO01 {
       nvidia,function = "gpio";
       nvidia,pull = "down";
       nvidia,tristate = "disable";
       nvidia,enable-input = "enable";
     }
     

5. Verify Configuration:

   • After making changes, compile and flash the new configuration to your Jetson Orin Nano Dev board.
   • Test the GPIO01 state immediately after power-up to confirm the changes.

6. Consult Nvidia Developer Forums:

   • If issues persist, seek assistance on the official Nvidia Developer Forums.
   • Provide detailed information about your board version, current configuration, and the exact changes you’ve attempted.

7. Consider Hardware Solution:

   • As a last resort, if software configuration proves challenging, consider using an external pull-down resistor on GPIO01 to ensure a low state on power-up.

Remember to back up your original configuration files before making any changes. If you encounter any errors during the process, revert to the original configuration and seek further assistance from the Nvidia support channels.