There are several projects being developed using Arduino and RFID Reader. But somehow the simple way of code for comparing the RFID Tag read from Reader with an array list of RFID Tags read from Serial Monitor was not found. So, I have made the following code and it works fine with UNO.
#include <SoftwareSerial.h> //Helps in Pin management
#include <string.h> //Helps in String Manipulation
#define EM_18_TX_PIN 9 //Pin to Read from Em-18 Reader
#define EM_18_RX_PIN 10 //Dummy Declaration
int GateOpenPin = 13;
SoftwareSerial serialEM18DREADER(EM_18_TX_PIN, EM_18_RX_PIN); //Defines Software Serial to EM-18 Reader.
// Now connect EM-18 Pin to D-09 Pin on Arduino.
// With such use, you need not unpin to write to Arduino.
//Variables to manage Reading RFID Data
int count = 0;
char RFIDtag[12] = {0}; //RFID Card number is Stored here after being read from EM-18 Reader
boolean newData = false;
//AuthTags is the list of Authorised RFID Card Numbers that you read from Serial Monitor.
//I have put only two here. If you want to add more numbers, then put , after the {"10004B6BD9E6"} and press enter.
// Then Put your new Numbers like this {"#####..."}, and then press enter and repeat the process
char AuthTags[][12] = {
{"10004B50E7EC"},
{"10004B6BD9E6"}
};
void setup() {
Serial.begin(9600);
while (!Serial) {
;//Waits for Aruduino to get ready
}
Serial.println("Arduino Ready");
serialEM18DREADER.begin(9600);
while (!serialEM18DREADER) {
;//Waits for EM-18 Reader to get ready
}
Serial.println("EM-18 Ready");
while (Serial.available() > 0 ) {
Serial.read();
}
}
void loop() {
if (serialEM18DREADER.available() > 0)
{
count = 0;
while (count < 12)
{
while (!serialEM18DREADER.available()) {
}
RFIDtag[count++] = serialEM18DREADER.read();
}
if (RFIDtag)// If RFIDtag vairable has data then process else continue
{
if (memcmp(RFIDtag, AuthTags, 12) == 0)
{ Serial.println(RFIDtag);//Displays the RFIDTag if found in the authorised list.
//You may use following funtion to generate a High Pulse on Pin No 13 to trigger the Gate Opening
digitalWrite(GateOpenPin, HIGH);
delay(5000);//Wait for Five seconds to keep the gate open
digitalWrite(GateOpenPin, LOW);//Lock the gate after Five second
memset(RFIDtag, NULL, 12); //Fills the RFIDtag array with Null Chars. Something like flusing the variable empty.
}
else {
Serial.println("RFID Not Found");
memset(RFIDtag, NULL, 12);
}
}
}
}