ResetComPort

Reset a specified COM port

This function block sends a COM port reset request to a specified port number. The PLC has to be set to "program controlled" communication. Evaluate the output variables bIsDone and bIsRequested to check if the specified port is reset and can be used again.

Parameters

Input

bReset (BOOL)

If set to TRUE, the COM port reset request is sent to the specified port number

Port (WORD, INT, UINT)

Port number

COM0, COM1, COM2 on CPU
16#xx01–16#xx04 (xx = slot number 1–64) on SCU

Output

bIsDone (BOOL): Set to TRUE, if the COM port is reset and can be used again.
bIsRequested (BOOL): Set to TRUE, if the COM port reset is requested.

Corresponding system variables of outputs (set only, if the COM port has been reset by bReset of the same instance)

Request to reset
- COM0: sys_bIsComPort0ResetRequested
- COM1: sys_bIsComPort1ResetRequested
- COM2: sys_bIsComPort2ResetRequested
Reset is done
- COM0: sys_bIsComPort0ResetDone
- COM1: sys_bIsComPort1ResetDone
- COM2: sys_bIsComPort2ResetDone

Example

POU header

All input and output variables used for programming this function have been declared in the POU header. The same POU header is used for all programming languages.

	VAR
		fbResetComPort: ResetComPort;
		bResetComPort: BOOL:=FALSE;
		iPort: INT:=0;
		bComPortCannotBeUsed: BOOL:=FALSE;
	END_VAR

POU body

When the variable bResetComPort is set to TRUE, the function block is carried out.

LD body

BODY
    WORKSPACE
        NETWORK_LIST_TYPE := NWTYPELD ;
        ACTIVE_NETWORK := 0 ;
    END_WORKSPACE
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 5 ;
        NETWORK_BODY
B(B_VARIN,,iPort,19,3,21,5,);
B(B_CONTACT,,bResetComPort,6,2,8,4,);
B(B_FB,ResetComPort!,fbResetComPort,21,1,30,5,,?BbReset?BPort?AbIsDone?AbIsRequested);
L(1,3,6,3);
L(8,3,21,3);
L(1,0,1,5);
        END_NETWORK_BODY
    END_NET_WORK
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 3 ;
        NETWORK_BODY
B(B_COIL,,bComPortCannotBeUsed,39,1,41,3,S);
B(B_CONTACT,,fbResetComPort.bIsRequested,6,1,8,3,);
L(1,2,6,2);
L(8,2,39,2);
L(1,0,1,3);
        END_NETWORK_BODY
    END_NET_WORK
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 3 ;
        NETWORK_BODY
B(B_COIL,,bComPortCannotBeUsed,39,1,41,3,E);
B(B_CONTACT,,fbResetComPort.bIsDone,6,1,8,3,);
L(1,2,6,2);
L(8,2,39,2);
L(1,0,1,3);
        END_NETWORK_BODY
    END_NET_WORK
END_BODY

ST body

fbResetComPort(bReset := bResetComPort,
               Port := iPort);
               IF (fbResetComPort.bIsRequested) then
                   bComPortCannotBeUsed := TRUE;
               ELSIF (fbResetComPort.bIsDone) then
                   bComPortCannotBeUsed := FALSE;
               END_IF;