WIZnet Developer Forum

Wiz108 sr server mode problem

Hello ,
I have problems receiving data from ethernet to serial.
Data transmission from serial to ethernet is ok!!!
To achieve this direction of transmission, I use Wiznet´s Config Tools to configure the WIZ108sr in CLIENT MODE. I used Hercules and Hyperterminal to check the communication.
The data transmission from ethernet (hercules) side was unsuccessful but data flows from serial side quite well.
The serial speed is 19200 baud, 8 bites, 1 stop, parity: none, flow control: none.
Configured the WIZ either as CLIENT or as SERVER (tcp mixed) the data always goes from the serial side to the ethernet side.

Firmware : WIZ108SRv4_06.bin


operation mode for device: Tcp mixed
Remote Ip:

Enable debug message output :yes
Comport setting :19200/8/n/1/none
Serial data packing cond: Timer:200

I will appreciate your kind help.


All our serial to ethernet module just bypass received data from one side to the other side.
If you can send data from serial to the server which is connected to WIZ108SR, TCP connection must be established well.
Under the connection established, WIZ108SR should bypass data from ethernet side to the serial port on it.
There is no option to block data from ethernet side.

Did you check if data from the server (i.e. the peer system which WIZ108SR communicated to) really deliver to the ethernet side of WIZ108SR?
You can see it with wireshark.exe program.
The best way to capture packet which is delivered to the ethernet part of WIZ108SR is to connect WIZ108SR to the server and to run wireshark.exe on the server.

Please check it first.

Thank you.


hello ,

The network capture result :

The 0.130 machine sent on Tcp “HELLO to 0.155 (wiz108sr)”

4 0.412835 IPA 61 unknown 0x4c

0000 00 08 dc 4f 29 ce 24 0a 64 8a c0 c7 08 00 45 00 …O).$.d…E.
0010 00 2f 55 de 40 00 80 06 22 7d c0 a8 00 82 c0 a8 ./U.@…"}…
0020 00 9b c7 4a 13 88 21 7e af 4c 05 3f 90 b4 50 18 …J…!~.L.?..P.
0030 44 38 b9 ef 00 00 48 45 4c 4c 4f 0d 0a D8…HELLO…

Feddback :
5 0.413648 TCP 60 5000 → 51018 [ACK] Seq=1 Ack=8 Win=8185 Len=0

0000 24 0a 64 8a c0 c7 00 08 dc 4f 29 ce 08 00 45 00 $.d…O)…E.
0010 00 28 00 6e 40 00 80 06 77 f4 c0 a8 00 9b c0 a8 .(.n@…w…
0020 00 82 13 88 c7 4a 05 3f 90 b4 21 7e af 53 50 10 …J.?..!~.SP.
0030 1f f9 cb d5 00 00 00 00 00 00 00 00 …

It is correct or not ?
Any idea ?
And obviously on the rs485 line is empty.



ACK message from WIZ108SR has ACK number 8 and it means that WIZ108SR received 7 bytes from the peer.
It looks working well.

By the way, which operation mode do you use, RS485 or RS422 and how did you set J2 PIN 10, 485_SEL pin?

I doubt that you did misconfiguration to it.
Will you check it again and let me know it?

Thank you.


hello ,

If I tried the reverse direction its works well,no chr problem … so its perfect.(Rs485–>Ethernet–>Remote server)
And if I sent back on this opened connection any answare (remote server–>Ethernet–>Rs485) works well.

The question is … what the difference between the two socket opening procedure.


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