Enable 1-Wire on Jetson Orin DevKit

Issue Overview

Users are experiencing difficulties enabling 1-Wire communication for the DS18B20 temperature sensor on the Nvidia Jetson Orin DevKit. The main symptoms include failure to read temperature data despite configuring the kernel settings for 1-Wire support. Specifically, users have enabled the following configuration options:

• CONFIG_W1=y
• CONFIG_W1_MASTER_GPIO=y
• CONFIG_W1_SLAVE_THERM=y

After building and flashing the kernel image, attempts to use the w1-gpio-cl module have not succeeded on any GPIO pin. The issue appears to occur during setup when users attempt to connect the sensor and read data. There is inconsistency in user experiences, with some reporting success on other Nvidia boards like the AGX Xavier but not on the Orin. The impact of this issue is significant as it prevents users from utilizing temperature sensors in their applications.

Possible Causes

• Hardware Incompatibilities or Defects: The Jetson Orin may have specific GPIO pin requirements that are not met by the current configuration.
• Software Bugs or Conflicts: There could be bugs in the kernel or conflicts with other modules that interfere with 1-Wire functionality.
• Configuration Errors: Incorrect GPIO pin assignments or missing configurations could prevent proper communication.
• Driver Issues: The drivers for 1-Wire may not be fully compatible with the Jetson Orin hardware.
• Environmental Factors: Issues such as power supply inconsistencies or temperature could affect GPIO performance.
• User Errors or Misconfigurations: Users may be incorrectly setting up their hardware connections or configurations.

Troubleshooting Steps, Solutions & Fixes

1. Verify Kernel Configuration:

   • Ensure that the kernel options for 1-Wire are correctly set and recompile if necessary.

2. Check GPIO Pin Compatibility:

   • Utilize AON GPIO pins for 1-Wire communication. The following pins are available:
     • GPIOs 316-347 (e.g., gpio-316, gpio-317, etc.)
   • Confirm that the chosen GPIO pin is indeed an AON pin by referencing the Jetson Orin documentation.

3. Testing with an Oscilloscope:

   • Connect an oscilloscope to the selected GPIO pin to monitor voltage changes during sensor communication attempts. This can help identify if signals are being sent/received correctly.

4. Use Correct Wiring:

   • Ensure that the DS18B20 sensor is wired correctly according to specifications, especially paying attention to pull-up resistor requirements.

5. Load w1-gpio Module Manually:

   • Use terminal commands to manually load the w1-gpio module:

     sudo modprobe w1-gpio
     sudo modprobe w1-therm
     

6. Check System Logs:

   • Review system logs for any error messages related to GPIO or 1-Wire communications:

     dmesg | grep w1
     

7. Update Firmware and Drivers:

   • Ensure that your Jetson Orin is running the latest firmware and drivers. Refer to NVIDIA’s documentation for instructions on updating.

8. Consult Documentation and Community Forums:

   • Check NVIDIA’s official documentation and community forums for additional insights or similar issues reported by other users.

9. Potential Workarounds:

   • If communication continues to fail, consider using alternative methods or libraries for interfacing with temperature sensors that may offer better compatibility with Jetson Orin.

10. Future Prevention:

    • Regularly check for updates from NVIDIA regarding kernel patches or driver updates that may address known issues with 1-Wire support.

By following these troubleshooting steps, users should be able to diagnose and potentially resolve issues related to enabling 1-Wire communication on their Nvidia Jetson Orin DevKit.