WIZ108SR mixed TCP and UDP corrupts data

Hi everybody,
We use the WIZ108SR in our projects and more than 20 pieces are installed at customers.
We have been investigating a long time (more than 1 year) to find why error of communications occurred, and I finally found it today:

The scenario is the following:

  • PC ask for someting to the client and receive an answer through wiznet module. This happens continuously.
  • Sometimes, PC needs to ‘browse’ the network and for this, send a broadcast message with a configuration string (MA, MC, LI, PT, …). Wiznet module answers with its configuration, but DURING THE SAME TIME, client was sending data to the serial interface of the wiznet module.
  • When the answer comes to the PC, we see with WireShark that the frame has been corrupted (generally 7 or 8 bytes missing).

This problem can be reproduced at 100%.

How can we solve it? Please help…

[ul]WIZ108SR HW 1.1 FW 2.20
Static ip
Server Mode
Packing time of 3ms
Serial at 115200, N, 8, 1[/ul]


Hi Eric.
Did you applied H/W flow control options (CTS/RTS)?
If not, I recommend that you apply as possible.
Please post the results reply.


How is it possible to apply H/W flow control to a 485 type communication?
There is only 4 wires for differential communication…
Best regards

Sorry Eric.
I confused with WIZ107SR module.
I will check this problem, then post the reply soon.


Hi Eric,
Didi you find a solution or could you reproduce the problem?