VAR_OUTPUT crc_value:WORD; END_VAR VAR_TEMP flag:WORD i, j:INT; END_VAR
BEGIN #j:=0 ; FOR #j:=0 TO (#字节数-1) BY 1 DO #crc_value:=PEEK(area:=b#16#84, dbNumber:=#输入起始地址, byteOffset:=#j) ; #crc_value:= #crc_value XOR 16#ffff ; FOR #i:= 0 TO 7 BY 1DO #flag := #crc_value AND 16#0001 ; #crc_value:=SHR(IN:=#crc_value, N:=1); IF #flag=0 THEN #crc_value:= #crc_value XOR 16#00; ELSIF #flag=1 THEN #crc_value:= #crc_value XOR 16#a001; END_IF; END_FOR; END_FOR; END_FUNCTION