FB_Connect

This function block enables to establish or terminate a TCP connection.

Syntax

FUNCTION_BLOCK FB_Connect IMPLEMENTS I_Connect
VAR_OUTPUT
    bBusy                        : BOOL;
    bError                       : BOOL;
    eState                       : E_SocketConnectionState;
    ipResultMessage              : I_TcMessage; 
END_VAR

Outputs

Name	Type	Description
bBusy	BOOL	Is TRUE as long as the asynchronous request is still active. Is FALSE if the request was completed or an error occurs.
bBusy	BOOL	Is set if an error occurs during the execution of the function block. Error details are located in the "Error List" window.
eState	E_SocketConnectionState	Returns the current connection state. eSOCKET_DISCONNECTED: disconnected eSOCKET_SUSPENDED: state between connected and disconnected eSOCKET_CONNECTED: connected
ipResult Message	I_TcMessage	Enables error handling with the `Tc3_EventLogger`.

Methods

Name	Description
FB_init	Initialization method
Connect	Establish a TCP connection.
Disconnect	Terminate a TCP connection.
Send	Send the QRC frame.
Receive	Receive the QRC frame.
FB_exit	Online Change method

	Because all methods are asynchronous and they need more than one cycle to finish working, only one method could be invoked at the same time. Therefore, check the output parameter `bBusy` when one of these methods is being called.

Properties

Properties	Type	Access	Description
aRxFrame	ARRAY[0..QRC_NUMBER_OF_CONTROL] OF T_MaxString	Get	As soon as the falling edge of `bBusy` occurs and `bError` is FALSE, the received QRC response frame can be get with this property.
sTxFrame	STRING(QRC_BUFFER_SIZE)	Set	As soon as the falling edge of `bBusy` occurs and `bError` is FALSE, the QRC frame to be sent can be set with this property.

Interface

Name	Description
I_Connect	The interface that defines communication related methods.

Further Information