Jetson Orin Nano CAN Bus Error

Issue Overview

Users are experiencing difficulties when attempting to read CAN bus data using Python on the Nvidia Jetson Orin Nano Developer Kit. The primary symptoms include:

• Failure of commands to execute in the terminal, particularly when verifying the CAN interface.
• Inability to locate the mttcan interface in the /proc/device-tree/ directory.
• Users report that they have followed the official NVIDIA documentation but encounter issues at the initial command stage.

The problem occurs after setting up the device and attempting to run commands related to the CAN interface. The user is operating on Jetpack version 6 and has performed a firmware update. The issue appears to be consistent, as multiple users have reported similar challenges.

The impact of this problem significantly hinders the ability to utilize CAN communication, which is essential for many applications in robotics and automation.

Possible Causes

• Hardware Incompatibilities or Defects: If the hardware does not support CAN bus or if there are defects in the developer kit, it could lead to these issues.

• Software Bugs or Conflicts: Bugs in Jetpack version 6 or conflicts with other installed software could prevent proper operation of the CAN interface.

• Configuration Errors: Incorrect setup of the CAN interface or missing configurations may lead to commands not executing as expected.

• Driver Issues: The mttcan driver may not be loaded properly, which would prevent access to CAN functionalities.

• Environmental Factors: Issues such as inadequate power supply or overheating could affect performance and availability of hardware features.

• User Errors or Misconfigurations: Users may overlook necessary steps in the setup process, leading to issues with command execution.

Troubleshooting Steps, Solutions & Fixes

1. Verify Hardware Setup:

   • Ensure that you are using a compatible developer kit and that all connections are secure.

2. Check Jetpack Version:

   • Confirm that you are running Jetpack version 6. You can check this by running:

     dpkg -l | grep nvidia-jetpack
     

3. Load the mttcan Driver:

   • Run the following command to load the mttcan driver:

     sudo modprobe mttcan
     

   • After running this command, check if you can see mttcan in /proc/device-tree/.

4. Follow Official Documentation:

   • Refer to the "Controller Area Network (CAN) — NVIDIA Jetson Linux Developer Guide" for detailed setup instructions. Make sure all steps are followed correctly.

5. Check Driver Status:

   • After loading the driver, verify its status by running:

     dmesg | grep mttcan
     

   • This will show any error messages related to loading the driver.

6. Test Commands:

   • Try executing basic CAN commands again after ensuring that mttcan is loaded correctly. For example:

     ip link show
     

7. Reinstall Drivers (if necessary):

   • If issues persist, consider reinstalling relevant drivers or performing a complete reinstallation of Jetpack.

8. Check for Updates:

   • Ensure your system is up-to-date with all patches and updates for Jetpack and related software.

9. Community Support:

   • If problems continue, consider reaching out on forums or NVIDIA support channels for additional assistance.

10. Best Practices for Future Prevention:

    • Regularly check for firmware and software updates.
    • Follow setup guides closely and ensure all dependencies are installed before proceeding with development tasks.

Unresolved aspects may include specific interactions between different software versions and hardware configurations that require further investigation. If multiple users report success with loading the mttcan driver as a solution, it should be highlighted as a recommended approach for troubleshooting this issue.