Hi everyone,
I try to configure the Modbus tcp ,but i cant't find the address ,it lead connect lost for modbus_tcp_slave ,as follows,how can i do?

/Javkin

Hi JavKin,
You should be know the modbus server side. IP Address. Port for Modbus TCP, defalut is 502，And the Unit ID, that is the device ID or connect ID to connect. Of course you need make sure the Modbus TCP data is exit in your sever side. that you want to write or read. you can use modscan32 to test. Or configure a modbus tcp server with proview. and test it. it's convenient use VM to test it. If you communicate with Siemens's PLC. You must program to use modbus TCP server.
You need call "MB_SERVER" function block to create the modbus TCP Server. defined the IP Address. port, connect ID. And the Data area. such as 10 int.
In the proview side you set the IP Address, port, unit ID to match the Siemens PLC(the example is s7-1200), if in the proview you write address from 0, that you can write 10 int type to Siemens PLC from DB*.DBW00, If you write the address from 6 that mean you will write from DB*.DBW6-DBW9. only 4 int.

Modbus TCP/IP embedds modbus RTU protocol. Address field (8 bits unsigned) is use to identify slave Remote Terminal Unit. It as no use in modbus TCP because you use IP adress instead except if you use Mosbus RTU slaves through a Modbus TCP / Modbus RTU gataeway (the gateway has the IP address and slave 8 bits address)

/Bruno