FUNCTION "CRC1" : Void
{ S7_Optimized_Access := 'TRUE' }
VERSION : 0.1
   VAR_INPUT 
      CrcData : Variant;
   END_VAR

   VAR_OUTPUT 
      CrcValue : Word;
      CrcErr : Word;
   END_VAR

   VAR_TEMP 
      Preset : Word;
      LoopLength : Int;
      ArrayPoint : Int;
      i : Int;
      ArrayLength : UDInt;
      Array1 : Array[0..999] of Byte;   // 最多1000個(gè)字節(jié)
      Err : Int;
   END_VAR


BEGIN
	#ArrayLength:= CountOfElements(#CrcData);
	
	IF #ArrayLength <= 1000 THEN //這里的1000如果需要調(diào)大,對(duì)應(yīng)的數(shù)組臨時(shí)變量Array1也要調(diào)大
	    #Err := MOVE_BLK_VARIANT(SRC := #CrcData, COUNT := #ArrayLength, SRC_INDEX := 0, DEST_INDEX := 0, DEST => #Array1);
	    #Preset := 16#FFFF;
	    #LoopLength := 0;
	    #ArrayPoint := 0;
	    
	    //計(jì)算CRC校驗(yàn)碼
	    WHILE #LoopLength < #ArrayLength DO    //數(shù)據(jù)長(zhǎng)度
	        #Preset := #Preset XOR #Array1[#ArrayPoint];
	        #ArrayPoint := #ArrayPoint + 1;
	        FOR #i := 0 TO 7 DO
	            IF (#Preset AND 16#01) = 16#01 THEN
	                #Preset := SHR(IN := #Preset, N := 1);
	                #Preset := #Preset XOR 16#A001;
	            ELSE
	                #Preset := SHR(IN := #Preset, N := 1);
	            END_IF;
	        END_FOR;
	        #LoopLength := #LoopLength + 1;
	    END_WHILE;
	    
	    //#CrcValue := #Preset;
	    #CrcValue := SHR_WORD(IN := #Preset, N := 8) + SHL_WORD(IN := #Preset, N := 8);
	    #CrcErr := 16#0000;
	ELSE
	    #CrcErr := 16#8000;
	END_IF;
	
END_FUNCTION

DATA_BLOCK "SEND1"

{ S7_Optimized_Access := 'FALSE' }

VERSION : 0.1

NON_RETAIN

STRUCT

CrcData : Array[0..5] of Byte; // 該數(shù)組不大于1000字節(jié)

CrcValue : Word;

CrcError : Word;

END_STRUCT;

BEGIN

CrcData[0] := 16#01;

CrcData[1] := 16#03;

CrcData[2] := 16#00;

CrcData[3] := 16#00;

CrcData[4] := 16#00;

CrcData[5] := 16#01;

END_DATA_BLOCK

FUNCTION "CRC2" : Void

{ S7_Optimized_Access := 'TRUE' }

VERSION : 0.1

VAR_INPUT

Command : Variant;

dataLen : Int;

END_VAR

VAR_TEMP

buffer : Array[0..#MaxLen] of Byte;

i : Int;

j : Int;

CrcReg : Word;

Len : Int;

END_VAR

VAR CONSTANT

MaxLen : Int := 255;

END_VAR

BEGIN

IF #dataLen = 0 OR #dataLen > CountOfElements(IN := #Command) - 2 THEN

RETURN;

ELSE

#Len := #dataLen;

END_IF;

#CrcReg := 16#FFFF;

//將數(shù)據(jù)轉(zhuǎn)到緩沖區(qū)

VariantGet(SRC:=#Command,

DST=>#buffer);

//計(jì)算CRC校驗(yàn)碼

FOR #i := 0 TO (#Len - 1) DO

#CrcReg := #CrcReg XOR #buffer[#i];

FOR #j := 0 TO 7 DO

IF (#CrcReg AND 16#1) = 1 THEN

#CrcReg := SHR_WORD(IN := #CrcReg, N := 1);

#CrcReg := #CrcReg XOR 16#A001;

ELSE

#CrcReg := SHR_WORD(IN := #CrcReg, N := 1);

END_IF;

END_FOR;

END_FOR;

#buffer[#Len + 1] := SHR_WORD(IN := #CrcReg, N := 8);

#buffer[#Len] := #CrcReg AND 16#FF;

//將緩沖區(qū)數(shù)據(jù)再寫(xiě)入到指針?biāo)赶虻膮^(qū)域

VariantPut(SRC := #buffer,

DST := #Command);

END_FUNCTION

DATA_BLOCK "SEND2"

{ S7_Optimized_Access := 'FALSE' }

VERSION : 0.1

NON_RETAIN

STRUCT

CrcData : Array[0..7] of Byte; // 該數(shù)組不大于1000字節(jié)

END_STRUCT;

BEGIN

CrcData[0] := 16#01;

CrcData[1] := 16#03;

CrcData[2] := 16#00;

CrcData[3] := 16#00;

CrcData[4] := 16#00;

CrcData[5] := 16#01;

END_DATA_BLOCK