Arduino กับ RFID

/*
 * rfidrelay.c
 *
 * Signals HIGH voltage to a relay when a proper code is received from an RFID
 * swipe event, and switches the voltage back to LOW when the RFID card is
 * swiped again.
 *
 * Authors: Blake Beaupain & Andrew Stucky
 */

#include <SoftwareSerial.h>

#define rxPin 8
#define txPin 9
#define RFID_PIN 2
#define RELAY_PIN 5
#define NUM_CODES 2

// The transmitting flag
int TRANSMITTING = 0;

// The RFID chip code
char *expected_codes[NUM_CODES];

/*
 * Sets up the device
 */
void setup() {
 Serial.begin(2400); // Hardware serial for Monitor 2400bps
 expected_codes[0] = "8400336CFF";
 expected_codes[1] = "00005D7E5C";
 
 // Activate the RFID reader
 pinMode(RFID_PIN, OUTPUT);
 digitalWrite(RFID_PIN, LOW);
 
 // Activate the relay pin
 pinMode(RELAY_PIN, OUTPUT);
 analogWrite(RELAY_PIN, 0);
}

/*
 * Main logic loop
 */
void loop() {
SoftwareSerial RFID = SoftwareSerial(rxPin,txPin); 
RFID.begin(2400);

 // Read data from the chip
 if (RFID.available() > 0) {
  // Read the full code
  char code[10];
  int amount = 0;
  while (amount < 10) {
   int data = RFID.read();
   if (data == 10 || data == 13)
   { Serial.println("Incomplete packet"); return; }// Incomplete packet
   code[amount++] = data;
  }
  
  // Authenticate the code
  int i, n, found = 0;
  for (i = 0; i < NUM_CODES; i++) {
   char *c = expected_codes[i];
   for (n = 0; n < 10; n++)
    if (code[n] != c[n])
     continue;
   found = 1;
   Serial.println("Pass"); //Passed Auth
  }
  if (found == 0)
  Serial.println("Fail"); //Failed Auth
    
  // Toggle the transmitting flag
  TRANSMITTING ^= 1;
  
  // Apply the proper voltage to the relay pin
  if (TRANSMITTING) {
   // Set to high voltage
   analogWrite(RELAY_PIN, 255);
  } else {
   // Set to low voltage
   analogWrite(RELAY_PIN, 0);
  }
  
  // Disable the RFID chip temporarily
  digitalWrite(RFID_PIN, HIGH);
  delay(2000);
  digitalWrite(RFID_PIN, LOW);
 }
}

ที่มา 

http://forum.arduino.cc/index.php/topic,87305.0.html

########################################################################
## Modified code to work with Arduino 1.0.1      /     ## 
## Credits to Petushka, http://www.instructables.com/member/Petushka/ ##
##                  ##
########################################################################

#include <SoftwareSerial.h>

#define ADD_TAG_CODE "210014DFE309"  //change this ID with your own card TAG
#define DEL_TAG_CODE "210014E2BD6A"  //change this ID with your own card TAG

SoftwareSerial rfid = SoftwareSerial(5, 6);
String msg;
String ID ;  //string to store allowed cards

void setup()  
{
  Serial.begin(9600);
  Serial.println("Serial Ready");

  rfid.begin(9600);
  Serial.println("RFID Ready");
}

char c;

void loop(){
  
  while(rfid.available()>0){
    c=rfid.read(); 
    msg += c;
    Serial.println(msg);  
    Serial.println(msg.length());
  }
  msg=msg.substring(1,13);
  if(msg.indexOf(ADD_TAG_CODE)>=0) add(); 
  else if(msg.indexOf(DEL_TAG_CODE)>=0) del();  
  else if(msg.length()>10) verifica();
  msg="";
  
}

void add(){
  Serial.print("What TAG do you wanna grant access?: ");
  msg="";
  while(msg.length()<13){
    while(rfid.available()>0){
      c=rfid.read(); 
      msg += c;
    }
  }
  if(ID.indexOf(msg)>=0) {
    Serial.println("\nAccess already granted for this card.");
    msg="";
  }
  else{
    Serial.print("Card: ");
    Serial.println(msg); 
    ID += msg;
    ID += ",";
    //Serial.print("ID: ");
   // Serial.println(ID);
    msg="";
    Serial.println("Access granted for this card.");
  }

}

void del(){
  msg="";
  Serial.print("What TAG do you wanna deny access?: ");
  while(msg.length()<13){
    while(rfid.available()>0){
      c=rfid.read(); 
      msg += c;
    }
  }
  msg=msg.substring(1,13);
  if(ID.indexOf(msg)>=0){
    Serial.println(msg);
    Serial.println("TAG found. Access for this card denied.");
    //ID.replace(card,"");
    int pos=ID.indexOf(msg);
    msg="";
    msg += ID.substring(0,pos);
    msg += ID.substring(pos+15,ID.length());
    ID="";
    ID += msg;
    //Serial.print("ID: ");
    //Serial.println(ID);
  } else Serial.println("\nTAG not found or already denied");
  msg="";
}

void verifica(){
    msg=msg.substring(1,13);
    if(ID.indexOf(msg)>=0) Serial.println("Access granted.");
    
    else Serial.println("Access denied.");
}



ที่มา 

http://www.instructables.com/files/orig/FM4/KU9W/H91LGBA6/FM4KU9WH91LGBA6.txt



#include <SoftwareSerial.h>
#include <SimpleTimer.h>

#define TAG_CODE "0800683B9BC0"  //change this ID with your own card TAG
int led3 = 3;
int wd_timer_id;
// The transmitting flag
int TRANSMITTING = 0;

SoftwareSerial rfid = SoftwareSerial(8, 9);
String msg;
String ID ;  //string to store allowed cards

SimpleTimer timer;

// function to be called just once
void OnceOnlyTask() {
  Serial.println("This timer only triggers once");  
 digitalWrite(led3, LOW); 
}

void setup()  
{
  Serial.begin(9600);
  Serial.println("Serial Ready");

  rfid.begin(9600);
  Serial.println("RFID Ready");
  
  pinMode(led3, OUTPUT); 
}

char c;

void loop(){
timer.run();
if(rfid.available()>0){
  while(rfid.available()>0){
    c=rfid.read(); 
    msg += c;
   // Serial.println(msg);  
   // Serial.println(msg.length());
  }
  msg=msg.substring(1,13);
  if(msg.length()==12) 
  Serial.println(msg);  
  ID = msg;
  msg="";
  if (ID.indexOf(TAG_CODE)>=0){
    Serial.println(ID);
    digitalWrite(led3, HIGH); 
    timer.deleteTimer(wd_timer_id);
    delay(1000);
    TRANSMITTING = 1;
  }


}else{
    //Serial.println(ID);
    if(TRANSMITTING){
      if(timer.getNumTimers()<=0){
                      timer.enable(wd_timer_id);
                      timer.setTimeout(5000, OnceOnlyTask);
      }
      TRANSMITTING = 0;
    }
  }
  
}