Originally created by: kees kraaijeveld

I have a wago controller programmed with CodeSys and a Proface screen ST403 and I have communication with Ethernet between these components

I have problems with the addresses

Codesys uses for instance addres 256 two times, for sending (word out) and receiving ( word in ).

The The sent information from Word out 256 returns to Word In 256

Does anyone have same experience, or a solution?

Hello kees,

at the follow link you can find a documentation about the plc-addresses

and the modbusfunctions for WAGO contollers and couplers

http://www.wago.com/wagoweb/documentati ... 00003e.pdf

If you use a 750-841 or a 750-842 normaly it is a better way to use the FB

"ETHERNET_TERMINAL_MODBUSSLAVE".

Inside the wago-specific library "ModbusEthernet_04.lib" (provided by WAGO)

you can find this FB.

This FB is an modbus-server and this server maps the modbusaddresses to

a wordarray inside the plc.

You can run this server at a free port (like 2500) in the plc.

At proface you have to adjust the communication to this port.

For more information please contact the wago support.

Note :

This informations are wago specific. Systems of other manufacturers can work by an other way.

Uwe

Zitat:
ETHERNET_TERMINAL_MODBUSSLAVE

is for Modbus on serial Port.

For Modbus Ethernet there's no library needed.

Hello Oberchefe,

i am sure ETHERNET_TERMINAL_MODBUSSLAVE is a modbus-TCP-server

for Ethernet not for serial ports.

For modbus at serial port you can use the library "TerminalSlave_04.lib" .

Both lib's have the same userinterface inside the plc so it is very easy

to switch from Modbus-TCP to Modbus-Serial.

Inside the firmware of the Wago-Controllers there is a Modbus-TCP-Server implemented on port 502.

You are right, for use this server you don't need a library.

But this server allows a direct access to the physical inputs / outputs and have an own

userinterface.

I think it's better to use ETHERNET_TERMINAL_MODBUSSLAVE as a second TCP-Server

on an other port.

So you can controll all outputs by the plc, you have a simple interface and it is easy

to switch to a serial communication

( you have only to replace ETHERNET_TERMINAL_MODBUSSLAVE by TERMINAL_MODBUSSLAVE_RTU_EN ).

This information is valid only for WAGO-Systems 841 / 842.

Uwe

Zitat:
i am sure ETHERNET_TERMINAL_MODBUSSLAVE is a modbus-TCP-server

You're right, for sure. I didn't realize "ETHERNET" in the name.