Siemens S7-400 - Programmed Communications Connections - Assigning Parameters to the Ports; Open TCP;IP Communication

Configuration and operation
6.9 Interface in the user program
CP 443-1 Advanced
Equipment Manual, 03/2023, C79000-G8976-C256-07
69
6.9.4 Programmed communications connections - assigning parameters to the
ports
The CP supports the following settings when assigning parameters to the ports in the
parameter block for TCP connections and UDP connections:
• SUB_LOC_PORT parameter
The port can be specified as an option when the connection is established actively.
• SUB_REM_PORT parameter
The port can be specified as an option when the connection is established passively.
6.9.5 Open TCP/IP communication
Use
To allow the user program to exchange data with other TCP/IPcompliant communication
partners, STEP 7 provides a UDT for the connection parameter assignment and four program
blocks (FBs):
• UDT 65 "TCON_PAR" with the data structure for connection parameter assignment
• FB65 "TCON" for connection establishment
• FB66 "TDISCON" for connection termination
• FB63 "TSEND" for sending data
• FB64 "TRCV" for receiving data
TCP/IP communication is connectionoriented. Data can be transmitted only when a
connection has been established to the communications partner. The CPU can use several
connections to a communications partner at the same time.
The following protocol variants are supported:
• ISO on TCP according to RFC 1006
Parameterization
Make the following parameter settings in the connection description (UDT 65):
• local_tsap_id: Byte 1 = 0xE0 (value mandatory for correct functionality)
• local_tsap_id: Byte 2 = rack/slot number
• remote_tsap_id: Byte 1 = 0xE0 (value mandatory for correct functionality)
• remote_tsap_id: Byte 2 = rack/slot number