WIZNET WIZ120SR Having Issue with Firmware Version 1.4

Question

Hi Wiznet Support team, We are having issue with WIZ120SR, where the serial to Ethernet data transmission is not successful. Out of the 50 modules purchased, 60% of it are having such issue. They are all tested under the same setup. After several debugging and probing, we rule out setup issue (IP domain, PWA, other components and software). We managed to resolve the issue by reloading the bootloader firmware of version 1.3 in WIZ120SR. By default, the module is loaded with version 1.4 . Note: The ROM bin file and boot loading procedures were given to me a year ago by WIZNET for firmware corruption resave purpose. I attach to you the wireshark capture of the Ethernet data, it seems like version 1.4 in WIZ102SR modules have difficulty to setup the serial port of 3001 and 3002. Serial data failed to be transmitted out. This failure symptom is similar for all the faulty modules. image961×336 320 KB My questions: Can I downgrade all of them to version 1.3? Our products are currently stuck in production due to this issue, we appreciate your quick feedback whether we can ship with version 1.3. We would like to know what is the difference between 1.3 and 1.4? What are the changes that trigger the change. We would also like to know what is the root cause of this? Is this a firmware bug? Assuming (3) is not valid, could this due the bootloader got damaged? It seems unlikely because we can still write and read the settings through the configuration tool. Please help to reply my questions as we need to keep our production going. Appreciate your quick feedback to solve this issue.

irina · Answer

We are looking for the cause of the problem. After finding the solution, I will post it here.