Beckhoff TX1200, Руководство пользователя

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Function blocks
TX1200 10 Version: 1.0
Sample of calling the function block in FBD:
PROGRAM MAIN
VAR
fbModbusOpen : FB_ModbusTcpOpen;
bOpen : BOOL;
bBusy : BOOL;
bError : BOOL;
nErrId : WORD;
nConnectionPort: WORD;
END_VAR
In this sample, a rising edge at the bOpen input causes a TCP/IP connection to the remote partner with
network address '172.16.2.209' to be established.
Requirements
Development environment Target platform PLC libraries to include
TwinCAT v2.7.0 and below BC9xxx (165) firmware version >=
0xB6 TcModbusTCPBC.Lb6
3.2 FB_ModbusTcpClose
The FB_ModbusTcpClose function block closes a connection to a remote partner that was opened with the
FB_ModbusTcpOpen [
}
9] function block. The number of IP connections that may be open is restricted to
four, in order to maintain the use of resources at a minimum. If it is necessary to establish a further
connection, a connection that is not currently in use must first be closed. A connection is automatically
closed after about 10 seconds if it is not used during that period. A confirmation from the remote partner is
not expected when a connection is closed. This means that under certain circumstances (e.g., if network
communication has been interrupted) it can happen that a connection still exists. The remote partner should
then close any such open connections. A Bus Controller operating as a remote partner closes such open
connections automatically.
VAR_INPUT
VAR_INPUT
bStart : BOOL;
sRemoteIPAddr: STRING(15);
iMyPortNo : WORD;
END_VAR
bStart : the function block is activated by a rising edge at this input.
sRemoteIPAddr : this variable is a string containing the network address (IP address) of the remote partner
whose connection is to be closed.