How to Write Custom ETH MAC Address to Orin Nano/NX with Customer Board

Issue Overview

Users are encountering difficulties when attempting to write a custom Ethernet MAC address to the Nvidia Jetson Orin Nano/NX development board, particularly in scenarios involving custom carrier boards that do not utilize EEPROM. The main symptoms reported include:

• Inability to modify the MAC address due to it being fused directly in the PHY (Physical Layer) of the device.
• Lack of available tools or commands from Nvidia for this specific modification, leading to confusion and frustration among users.

This issue typically arises during the configuration of custom hardware setups, where users expect to have control over MAC address assignment. The problem is consistent across multiple inquiries, indicating a widespread challenge among developers using custom boards. The impact on user experience is significant, as the inability to set a custom MAC address can hinder network configurations and device identification in various applications.

Possible Causes

• Hardware Limitations: The Ethernet MAC address is hardwired into the PHY, which means it cannot be altered through standard software methods.

• Lack of Tools: Users are unaware of or lack access to specific tools required for modifying the MAC address, which are not provided by Nvidia but may be available through third-party vendors like Realtek.

• Misunderstanding of Functionality: Users may assume that the MAC address can be modified similarly to other configurable parameters, leading to confusion when it cannot be changed.

Troubleshooting Steps, Solutions & Fixes

1. Confirm Hardware Specifications:

   • Ensure that you are using an Orin Nano/NX board and verify that it is indeed a custom carrier board without EEPROM.

2. Contact Realtek for Tools:

   • Since the MAC address is fused in the PHY, reach out to Realtek for any proprietary tools or commands that may allow modifications. This step is crucial as Nvidia does not provide direct support for this functionality.

3. Check Documentation:

   • Review any available documentation from Nvidia regarding the Orin Nano/NX boards to see if there are updates or notes on modifying hardware settings.

4. Isolation Testing:

   • If possible, test with different configurations or setups (e.g., using a standard devkit with EEPROM) to confirm that the issue is isolated to custom hardware setups.

5. Explore Workarounds:

   • If changing the MAC address is not feasible, consider alternative network configurations that do not rely on a custom MAC address.

6. Best Practices for Future Projects:

   • When designing custom boards, ensure that necessary features such as EEPROM for MAC address storage are included if customization is required.
   • Stay updated with community forums and Nvidia’s official channels for any new tools or updates regarding hardware modifications.

7. Documentation and Support Links:

   • Keep an eye on Nvidia’s developer forums and Realtek’s support channels for any announcements or new tools that may assist in this process.

8. Unresolved Aspects:

   • Further investigation may be needed regarding other potential methods for writing custom MAC addresses or alternative solutions that could be implemented in future designs.

By following these steps and recommendations, users can better navigate the challenges associated with setting a custom Ethernet MAC address on their Orin Nano/NX boards while utilizing customer carrier boards.