This function returns the status of the CTS signal of the serial port connected to the File parameter, previously opened with the FB SysSerialPort.
Function
CODESYS: Not available
LogicLab: eLLabXUnified12Lib
Description
File (FILEP) Stream data stream returned by the FB SysSerialPort.
The function returns a (BOOL) FALSE CTS signal not active, TRUE active CTS signal.
Examples
How to use the examples.
In the following example, a serial communication port is opened and the state of the CTS signal is acquired, which is placed on the variable CTSIn. The execution error control is managed in the program by checking if the last error has ObjectID 9993, relating to the function.
LogicLab (Ptp116), ST_SysGetSerialCTS
PROGRAM ST_SysGetSerialCTS
VAR
CTSIn : BOOL; (* CTS signal status *)
IsError : BOOL; (* Execution error *)
Sp : SysSerialPort; (* Serial port management *)
END_VAR
// *****************************************************************************
// PROGRAM "ST_SysGetSerialCTS"
// *****************************************************************************
// The program allows to read the status of the serial CTS signal.
// -----------------------------------------------------------------------------
// -------------------------------------------------------------------------
// INITIALIZATION
// -------------------------------------------------------------------------
IF (SysFirstLoop) THEN
Sp.COM:=ADR('COM0'); //COM port definition
Sp.Baudrate:=19200; //Baudrate
Sp.Parity:='E'; //Parity
Sp.DataBits:=8; //Data bits
Sp.StopBits:=1; //Stop bits
Sp.DTRManagement:=DTR_AUTO_WO_TIMES; //DTR management
Sp.DTRComplement:=FALSE; //DTR complement
Sp.EchoFlush:=FALSE; //Received echo flush
Sp.DTROnTime:=0; //DTR On time delay (mS)
Sp.DTROffTime:=0; //DTR Off time delay (mS)
Sp.FlushTm:=0; //Flush time (mS)
Sp.RxSize:=0; //Rx buffer size
Sp.TxSize:=0; //Tx buffer size
END_IF;
// -------------------------------------------------------------------------
// DTR MANAGEMENT
// -------------------------------------------------------------------------
// The DTR signal is managed.
Sp(Open:=TRUE); //Serial port management
IF (Sp.Opened) THEN
CTSIn:=SysGetSerialCTS(Sp.File); //CTS signal status
// To check if execution error, check if the return is FALSE and last
// error code has the function ObjectID.
IF NOT(CTSIn) THEN
IsError:=((SysGetLastError(TRUE)/1000) = 9993); //Execution error
END_IF;
END_IF;
// [End of File]