Inquiry on UDP Communication Usage and MAC-Related Changes in Typhoon HIL 2025.4

Question

Hello, I am currently working with the Ethernet UDP Communication module in Typhoon HIL and would like to seek your guidance regarding its correct usage for data transmission and reception, particularly after upgrading to version 2025.4.

In earlier software versions, I successfully implemented UDP-based communication using the UDP Send/Receive modules to exchange data between the HIL device and an external controller. However, after upgrading to version 2025.4, the same communication setup no longer functions as expected. During troubleshooting, I noticed that the UDP Communication module in the newer version introduces additional MAC address–related configuration options (e.g., source device MAC address and MAC override settings), which were not explicitly exposed or configurable in previous versions.

Based on this observation, I would like to kindly ask for clarification on the following points:

What is the recommended procedure for implementing reliable UDP data transmission and reception using the Ethernet UDP Communication modules in the current (2025.4) version?

What specific changes related to MAC address handling were introduced in or before version 2025.4?

Why might UDP communication models built with earlier versions (where MAC configuration was implicit or hidden) fail to operate correctly after upgrading?

Are there any mandatory MAC-related settings or migration steps required to ensure backward compatibility of existing UDP communication models?

Understanding the rationale behind these changes and the correct configuration approach would be very helpful for adapting our existing HIL models to the updated software environment.

Thank you very much for your time and support. I look forward to your guidance.

Answer 1

Hello,

You are correct — in newer versions, the UDP communication module includes an option to configure the MAC address, more precisely the last digit of the MAC address.
This option was not available in previous versions.

There was a bug in earlier versions related to MAC address handling, which we fixed by introducing this new feature. This change may have affected backward compatibility; however, since the functionality worked correctly before, there is no reason it should not work again once everything is properly configured.

Based on the fact that everything was working correctly before, it is clear that you have a good understanding of how UDP communication works. Therefore, there is nothing specific we need to advise you on in this regard.

It is only necessary to configure the last digit of the MAC address again.

Please override the last digit of the MAC address as follows:

Enable “Override last digit in MAC address”

If you were using eth port 2, enter 5 in the “Source device MAC address” field

If you were using eth port 3, enter 6 in the “Source device MAC address” field

If you were using eth port 4, enter 7 in the “Source device MAC address” field

If you continue to experience issues with UDP communication, I recommend using Wireshark as a debugging tool to verify the communication and confirm that the MAC address is set correctly.