W7500S2E-R1 is not receiving on UART and no TCP connection

I have a new W7500S2E-R1 module that I am testing with an evaluation board.
Initially I had it connected successfully UART and Ethernet communication and was configured as TCP server while getting the IP Address from DHCP Server (matching the subnet).

After running my code, this made successfull response AT commands from the module through UART interface and correct TCP connection8 and transmissions.

The problem is that after a few runs of the code, the module stopped responding.
On one hand, the module was not responding to UART transmissions sent via the evaluation board.
Which I think the problem might have been on some of the AT commands sent to the module that might have changed configuration(??). The AT commands I send are:

  • AT Diconnect → to ensure disconnection initially
    -AT Listen
    -AT TCP Status Read → both on a loop waiting for connection from the client (PC on Hercules tool recommended by WIZnet)

-AT Start mode = 0 → setting to AT command mode

  • AT terminal check → checking receiving
    -… and some others for reading IP, MAC address and so on.

These commands were received at first by the module as correct response back was happening. But after few runs of the code, no more responding happened.

And, on the other hand, now proper TCP connection is not possible (not with default IP address nor even got from DHCP Server). Now, on the configTool when the module is detected, it sates that the Firmware Version is 11.3 (and 2.8 is latest one) . And as no possible connection can be made anymore, no firmaware update can be made aswell.
Wird hochgeladen: Captura.PNG …

  • How is it possible that UART interface is not working anymore in the module if first 5 runs of the code worked perfectly?
  • How can I solve the TCP connection for further firmware updating?

Thank you,


Hi, I’m Ron from WIZnet HK.

Thank you for information about this issue.

We would suggested you to try to following.

  1. Try to Firmware upgrade the module to 2.8 Version.

  2. Factory reset the module

  3. Test the module.

For the firmware upgrade method, please refer to the youtube link below. (description will have timestamp for you to select firmware upgrade)

If the problem is still occur, please let us know through email.

Email address: support@wiznet.hk

Best Regards,