byte RFIDcardNum[4];
003
byte evenBit = 0;
004
byte oddBit = 0;
005
byte isData0Low = 0;
006
byte isData1Low = 0;
007
int recvBitCount = 0;
008
byte isCardReadOver = 0;
009
 
010
void setup()
011
{
012
  Serial.begin(9600);
013
  attachInterrupt(0, ISRreceiveData0, FALLING );  //data0/rx is connected to pin 2, which results in INT 0
014
  attachInterrupt(1, ISRreceiveData1, FALLING );  //data1/tx is connected to pin 3, which results in INT 1
015
pinMode(13, OUTPUT);
016
}
017
 
018
void loop()
019
{
020
   
021
  //read card number bit
022
  if(isData0Low||isData1Low){
023
    if(1 == recvBitCount){//even bit
024
      evenBit = (1-isData0Low)&isData1Low;
025
        
026
    }
027
    else if( recvBitCount >= 26){//odd bit
028
      oddBit = (1-isData0Low)&isData1Low;
029
      isCardReadOver = 1;
030
      delay(10);
031
       
032
      if (isCardReadOver == 9923104)
033
      
034
   {
035
       digitalWrite(13, HIGH);   // зажигаем светодиод
036
  delay(1000);              // ждем секунду
037
  digitalWrite(13, LOW);    // выключаем светодиод
038
  Serial.println(" hello ");
039
    }
040
  if (isCardReadOver == 9920544
041
)
042
  digitalWrite(13,  HIGH);
043
       digitalWrite(13, HIGH);   // зажигаем светодиод
044
  delay(9000);              // ждем секунду
045
  digitalWrite(13, LOW);    // выключаем светодиод
046
  Serial.println(" hello1 ");
047
   
048
    }
049
    else{
050
      //only if isData1Low = 1, card bit could be 1
051
      RFIDcardNum[2-(recvBitCount-2)/8] |= (isData1Low << (7-(recvBitCount-2)%8));
052
    
053
 
054
    }
055
    //reset data0 and data1
056
    isData0Low = 0;
057
    isData1Low = 0;
058
     
059
  }
060
 
061
  //print the card id number
062
  if(isCardReadOver){
063
    //if(checkParity()){
064
    //Serial.println();
065
    //Serial.print(RFIDcardNum[2],HEX);//High byte
066
    //Serial.print(RFIDcardNum[1],HEX);//Midle byte
067
    //Serial.println(RFIDcardNum[0],HEX);//Low byte
068
      Serial.println(*((long *)RFIDcardNum));
069
    //}
070
    resetData();
071
  }
072
 
073
}
074
 
075
byte checkParity(){
076
  int i = 0;
077
  int evenCount = 0;
078
  int oddCount = 0;
079
  for(i = 0; i < 8; i++){
080
    if(RFIDcardNum[2]&(0x80>>i)){
081
      evenCount++;
082
    }
083
  }
084
  for(i = 0; i < 4; i++){
085
    if(RFIDcardNum[1]&(0x80>>i)){
086
      evenCount++;
087
    }
088
  }
089
  for(i = 4; i < 8; i++){
090
    if(RFIDcardNum[1]&(0x80>>i)){
091
      oddCount++;
092
    }
093
  }
094
  for(i = 0; i < 8; i++){
095
    if(RFIDcardNum[0]&(0x80>>i)){
096
      oddCount++;
097
    }
098
  }
099
   
100
  if(evenCount%2 == evenBit && oddCount%2 != oddBit){
101
    return 1;
102
  }
103
  else{
104
    return 0;
105
  }
106
}
107
void resetData(){
108
  RFIDcardNum[0] = 0;
109
  RFIDcardNum[1] = 0;
110
  RFIDcardNum[2] = 0;
111
  RFIDcardNum[3] = 0;
112
  evenBit = 0;
113
  oddBit = 0;
114
  recvBitCount = 0;
115
  isData0Low = 0;
116
  isData1Low = 0;
117
  isCardReadOver = 0;
118
}
119
// handle interrupt0
120
void ISRreceiveData0(){
121
  recvBitCount++;
122
  isData0Low = 1;
123
}
124
 
125
// handle interrupt1
126
void ISRreceiveData1(){
127
  recvBitCount++;
128
  isData1Low = 1;
129
}