R1.3, R1.4 differences

Good morning,
I’ve a custom gear that mount WIZ107SR card to translate TCP-serial information.
My gear works with R1.3 version (firmware 3.11), but if I put R1.4 card (firmware 4.05 or 4.04), does not work.

Somone may help me? thanks.

There is no significant difference in hardware except for the added external WDT IC. so, revision 1.4 hardware can also be used to 3.xx version firmware. (backward (1.3) compatible with revision 1.4 hardware)
[Link] Old firmwares: wiznet.co.kr/product-item/wiz107sr/

However, we recommend that you are looking for the cause of the problem and utilizing the latest firmware for stability.
I append the following information for you. Please compare with your configurations.