• Open NetPro and insert a TCP connection.
• If S7 is modbus client the flag for "Active connection establishment" is TRUE, if S7 is modbus server this flag you have to set to FALSE.
• In next tab you have to set the port numbers:
  • If S7 is modbus client:
    The local port number is e.g. 2000 (default), the port number for the remote partner has to be 502 and you have to insert the ip address of the partner
  • If S7 is modbus server:
    The local port number has to be 502. If you use an unspecified connection the remote partner is empty. If you use a specific connection, then you have to insert the ip address and port number of the partner

S7 program:

• Insert the modbus block in OB100 and OB1 with the same instance DB.Parameterize the initialisation parameters in OB100 like it's described in the manualor the block online help (F1)
• Set the runtime parameters in OB1 like it's described in the manual.
• The best way is tohave a look at the example project, which is installed after the setup installation. Here you can see all needed parameters in OB100 and OB1.