VAR

uiComState : UINT;

xDone : BOOL;

aCom1Params : ARRAY [1..7] OF COM.PARAMETER;

aCom2Params : ARRAY [1..7] OF COM.PARAMETER;

como1 : COM.Open;

comc1 : COM.Close;

comw1 : COM.Write;

como2 : COM.Open;

comc2 : COM.Close;

comr2 : COM.Read;

 sWrite : STRING := 'Test String der Länge 25!';

 sRead : STRING(25);

 szRead : CAA.SIZE;

 xCom1OpenError : BOOL;

 xCom1CloseError : BOOL;

 xCom1WriteError : BOOL;

 xCom2OpenError : BOOL;

  xCom2CloseError : BOOL;

  xCom2ReadError : BOOL;

END_VAR

CASE uiComState OF

  0:

        aCom1Params[1].udiParameterId := COM.CAA.Parameter_Constants.udiPort;

        aCom1Params[1].udiValue := 1;

        aCom1Params[2].udiParameterId := COM.CAA.Parameter_Constants.udiBaudrate;

        aCom1Params[2].udiValue := 9600;

        aCom1Params[3].udiParameterId := COM.CAA.Parameter_Constants.udiParity;

        aCom1Params[3].udiValue := COM.PARITY.NONE;

        aCom1Params[4].udiParameterId := COM.CAA.Parameter_Constants.udiStopBits;

        aCom1Params[4].udiValue := COM.ONESTOPBIT;

        aCom1Params[5].udiParameterId := COM.CAA.Parameter_Constants.udiTimeout;

        aCom1Params[5].udiValue := 0;

        aCom1Params[6].udiParameterId := COM.CAA.Parameter_Constants.udiByteSize;

         aCom1Params[6].udiValue := 8;

         aCom1Params[7].udiParameterId := COM.CAA.Parameter_Constants.udiBinary;

         aCom1Params[7].udiValue := 0;

         como1.udiListLength := SIZEOF(aCom1Params)/SIZEOF(COM.PARAMETER);

         como1.pParameterList := ADR(aCom1Params);

         como1.xExecute := TRUE;

         como1();                                 

          IF como1.xError THEN

             xCom1OpenError := TRUE;

             uiComState := 1000;

           END_IF

           IF como1.xDone THEN

              uiComState := 5;

            END_IF

  5:

          aCom2Params[1].udiParameterId := COM.CAA.Parameter_Constants.udiPort;

          aCom2Params[1].udiValue := 2;

          aCom2Params[2].udiParameterId := COM.CAA.Parameter_Constants.udiBaudrate;

          aCom2Params[2].udiValue := 9600;

          aCom2Params[3].udiParameterId := COM.CAA.Parameter_Constants.udiParity;

          aCom2Params[3].udiValue := COM.PARITY.NONE;

          aCom2Params[4].udiParameterId := COM.CAA.Parameter_Constants.udiStopBits;

          aCom2Params[4].udiValue := COM.ONESTOPBIT;

          aCom2Params[5].udiParameterId := COM.CAA.Parameter_Constants.udiTimeout;

          aCom2Params[5].udiValue := 0;

          aCom2Params[6].udiParameterId := COM.CAA.Parameter_Constants.udiByteSize;

          aCom2Params[6].udiValue := 8;

          aCom2Params[7].udiParameterId := COM.CAA.Parameter_Constants.udiBinary;

          aCom2Params[7].udiValue := 0; // false

          como2.udiListLength := SIZEOF(aCom2Params)/SIZEOF(COM.PARAMETER);

          como2.pParameterList := ADR(aCom2Params);

           como2.xExecute := TRUE;

           como2();

        IF como2.xError THEN

              xCom2OpenError := TRUE;

              uiComState := 25;

         END_IF

         IF como2.xDone THEN

             uiComState := 10;

          END_IF

 10:

            comw1.hCom := como1.hCom;

            comw1.pBuffer := ADR(sWrite);

            comw1.szSize := 5;

            comw1.xExecute := TRUE;

            comw1();

            IF comw1.xError THEN

                 xCom1WriteError := TRUE;

            END_IF

            IF comw1.xDone THEN

                uiComState := 15;

             END_IF

 15:

             comr2.pBuffer := ADR(sRead);

             comr2.szBuffer := 25;

             comr2.hCom := como2.hCom;

             comr2.xExecute := TRUE;

             comr2();

             IF comr2.xError THEN

                  xCom2ReadError := TRUE;

             END_IF

             IF comr2.xDone OR comr2.xError THEN

                        IF comr2.xDone THEN

                         szRead := comr2.szSize;

                        END_IF

                       uiComState := 20;

               END_IF

 20:

               comc2.hCom := como2.hCom;

               comc2.xExecute := TRUE;

               comc2();

               IF comc2.xError THEN

                   xCom2CloseError := TRUE;

               END_IF

               IF comc2.xDone OR comc2.xError THEN

                    uiComState := 25;

               END_IF

25:

               comc1.hCom := como1.hCom;

               comc1.xExecute := TRUE;

               comc1();

               IF comc1.xError THEN

                   xCom1CloseError := TRUE;

               END_IF

               IF comc1.xDone OR comc1.xError THEN

                   uiComState := 1000;

               END_IF

 1000:

                xDone := TRUE;

ELSE

            uiComState := 0;          

END_CASE

Hardware handshake:

VAR

  aComParams : ARRAY [1..11] OF COM.PARAMETER;

END_VAR

aComParams[1].udiParameterId := COM.CAA.Parameter_Constants.udiPort;

aComParams[1].udiValue := 1;

aComParams[2].udiParameterId := COM.CAA.Parameter_Constants.udiBaudrate;

aComParams[2].udiValue := 9600;

aComParams[3].udiParameterId := COM.CAA.Parameter_Constants.udiParity;

aComParams[3].udiValue := COM.PARITY.NONE;

aComParams[4].udiParameterId := COM.CAA.Parameter_Constants.udiStopBits;

aComParams[4].udiValue := COM.ONESTOPBIT;

aComParams[5].udiParameterId := COM.CAA.Parameter_Constants.udiTimeout;

aComParams[5].udiValue := 0;

aComParams[6].udiParameterId := COM.CAA.Parameter_Constants.udiByteSize;

aComParams[6].udiValue := 8;

aComParams[7].udiParameterId := COM.CAA.Parameter_Constants.udiBinary;

aComParams[7].udiValue := 0; // false

// Handshake Parameter

aComParams[8].udiParameterId := COM.CAA.Parameter_Constants.udiDtrControl;

aComParams[8].udiValue := 16#02; // handshake

aComParams[9].udiParameterId := COM.CAA.Parameter_Constants.udiOutxDsrFlow;

aComParams[9].udiValue := 1; // true

aComParams[10].udiParameterId := COM.CAA.Parameter_Constants.udiRtsControl;

aComParams[10].udiValue := 16#02; // handshake

aComParams[11].udiParameterId := COM.CAA.Parameter_Constants.udiOutxCtsFlow;

aComParams[11].udiValue := 1; // true

// …..

Software handshake:

VAR

aComParams : ARRAY [1..14] OF COM.PARAMETER;

END_VAR

aComParams[1].udiParameterId := COM.CAA.Parameter_Constants.udiPort;

aComParams[1].udiValue := 1;

aComParams[2].udiParameterId := COM.CAA.Parameter_Constants.udiBaudrate;

aComParams[2].udiValue := 9600;

aComParams[3].udiParameterId := COM.CAA.Parameter_Constants.udiParity;

aComParams[3].udiValue := COM.PARITY.NONE;

aComParams[4].udiParameterId := COM.CAA.Parameter_Constants.udiStopBits;

aComParams[4].udiValue := COM.ONESTOPBIT;

aComParams[5].udiParameterId := COM.CAA.Parameter_Constants.udiTimeout;

aComParams[5].udiValue := 0;

aComParams[6].udiParameterId := COM.CAA.Parameter_Constants.udiByteSize;

aComParams[6].udiValue := 8;

aComParams[7].udiParameterId := COM.CAA.Parameter_Constants.udiBinary;

aComParams[7].udiValue := 0; // false

// Handshake Parameter

aComParams[8].udiParameterId := COM.CAA.Parameter_Constants.udiInX;

aComParams[8].udiValue := 1; // true

aComParams[9].udiParameterId := COM.CAA.Parameter_Constants.udiXonChar;

aComParams[9].udiValue := 17;

aComParams[10].udiParameterId := COM.CAA.Parameter_Constants.udiXonLim;

aComParams[10].udiValue := 2048;

aComParams[11].udiParameterId := COM.CAA.Parameter_Constants.udiOutX;

aComParams[11].udiValue := 1; // true

aComParams[12].udiParameterId := COM.CAA.Parameter_Constants.udiXoffChar;

aComParams[12].udiValue := 19;

aComParams[13].udiParameterId := COM.CAA.Parameter_Constants.udiXoffLim;

aComParams[13].udiValue := 512;

aComParams[14].udiParameterId := COM.CAA.Parameter_Constants.udiTXContinueOnXoff;

aComParams[14].udiValue := 0; // false

// …..