Navigation:  Libraries > CT Modbus Client > MODBUS_CLIENT_CONNECTION (FUNC)

This function block is used to establish a connection to the specified server and makes a request for the Function Code to be executed.

 

Inputs:

 

xExecute :  BOOL; Set to TRUE to execute the function block if the last execution state was FALSE.

 

pServer : POINTER TO T_SERVER_STRUCT; Pointer to the server to connect to.

 

pChannel : POINTER TO T_CHANNEL_STRUCT; Pointer to the channel to execute on the specified server.

 

xBlocking : BOOL; Defines if the function block is blocking or non-blocking.

 

 

Outputs:

 

xdone : BOOL; If TRUE the Function Code has been executed successfully.

 

xBusy : BOOL; The connection is in progress (preparing the request or waiting for the response).

 

xError : BOOL; The connection has detected an error.

 

udiErrorID : CLIENT_ERROR_CODES; In case or error the error code is specified.

 

 

Example in FBD:

 

 

 

Example in ST:

 

 

 FB_ModbusConnection: MODBUS_CLIENT_CONNECTION;

 

 IF NOT  FB_ModbusConnection.xBusy THEN

         IF NOT FB_ModbusConnection.xError THEN

 

 

                 // Read the response data

 

         END_IF

 END_IF