I've been working to a project that uses arduino for RFID but when connected to ethernet shield, the RFID seems to not read any card tapped to sensor but the LCD seems to do fine. Here's the code I use from this page: http://www.instructables.com/id/RFID-CARD-READER-WITH-ARDUINORFID-RC522-and-LCD-16/
#include <EEPROM.h> //Library To read and write PICC's UIDs from/to EEPROM
#include <SPI.h> //Library RC522 Module uses SPI protocol
#include <MFRC522.h> //Library RC522 Module
#include <LiquidCrystal.h> //Library for LCD Display
#include <Ethernet.h>
EthernetServer server(80);
boolean match = false; // initialize card match to false
boolean programMode = false; // initialize programming mode to false
int successRead; // Variable integer to keep if we have Successful Read from Reader
byte storedCard[4]; // Stores an ID read from EEPROM
byte readCard[4]; // Stores scanned ID read from RFID Module
byte masterCard[4]; // Stores master card's ID read from EEPROM
#define SS_PIN 10
#define RST_PIN 9
MFRC522 mfrc522(SS_PIN, RST_PIN); // Create MFRC522 instance.
LiquidCrystal lcd(7, 6, 5, 4, 3, 2); //Initializing LCD PINS as (RS, EN, D4, D5, D6, D7)
void setup() {
Serial.begin(9600); // Initialize serial communications with PC
lcd.begin(16, 2); //Initializing LCD 16x2
pinMode(8, OUTPUT); //LED and Buzzer PIN OUT
SPI.begin(); // MFRC522 Hardware uses SPI protocol
mfrc522.PCD_Init(); // Initialize MFRC522 Hardware
mfrc522.PCD_SetAntennaGain(mfrc522.RxGain_max);
if (EEPROM.read(1) != 1) {
// Look EEPROM if Master Card defined, EEPROM address 1 holds if defined
Serial.println("No Admin Card Defined");
//When no Master Card in Your EEROM (Serial Display)
Serial.println("Scan A card to Define as Admin Card");
lcd.clear();
lcd.setCursor(0, 0);
lcd.println("SET ADMIN CARD ");
//When no Master Card in Your EEROM (LCD Display)
lcd.setCursor(0, 1);
lcd.println("SCAN A CARD.....");
//Scan any RFID CARD to set Your Master Card in Your EEROM (LCD Display)
delay(1500);
do {
successRead = getID();
// sets successRead to 1 when we get read from reader otherwise 0
}
while (!successRead);
//the program will not go further while you not get a successful read
for (int j = 0; j < 4; j++) {
// Loop 4 times
EEPROM.write(2 + j, readCard[j]);
// Write scanned PICC's UID to EEPROM, start from address 3
}
EEPROM.write(1, 1); //Write to EEPROM we defined Master Card.
Serial.println("Admin Card Defined");
}
Serial.println("Administrator Card's UID");
for (int i = 0; i < 4; i++) { // Read Master Card's UID from EEPROM
masterCard[i] = EEPROM.read(2 + i); // Write it to masterCard
Serial.print(masterCard[i], HEX); //Master Card only view in serial
Serial.println("Waiting PICCs to bo scanned :)");
}
//WAITING TO SCAN THE RFID CARDS:
Serial.println("");
Serial.println("Waiting cards to bo scanned :)");
lcd.clear();
lcd.setCursor(4, 0);
lcd.println("WAITING ");
lcd.setCursor(3, 1);
lcd.println("FOR CARD... ");
delay(1500);
}
int getID() {
// Getting ready for Reading PICCs
if (! mfrc522.PICC_IsNewCardPresent()) {
//If a new PICC placed to RFID reader continue
return 0;
}
if (! mfrc522.PICC_ReadCardSerial()) {
//Since a PICC placed get Serial and continue
return 0;
}
// There are Mifare PICCs which have 4 byte or 7 byte UID care if you use 7 byte PICC
// I think we should assume every PICC as they have 4 byte UID
// Until we support 7 byte PICCs
Serial.println("Scanning card's UID....");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("SCANNING");
lcd.setCursor(0, 1);
lcd.print("Card's UID.....");
delay(2000);
for (int i = 0; i < 4; i++) {
readCard[i] = mfrc522.uid.uidByte[i];
Serial.print(readCard[i], HEX);
}
Serial.println("");
mfrc522.PICC_HaltA(); // Stop reading
return 1;
}
boolean isMaster(byte test[]) {
if (checkTwo(test, masterCard))
return true;
else
return false;
}
boolean checkTwo (byte a[], byte b[]) {
if (a[0] != NULL)
// Make sure there is something in the array first
match = true;
// Assume they match at first
for (int k = 0; k < 4; k++) {
// Loop 4 times
if (a[k] != b[k])
// IF a != b then set match = false, one fails, all fail
match = false;
}
if (match) {
// Check to see if if match is still true
return true;
} else {
return false;
}
}
boolean findID(byte find[]) {
int count = EEPROM.read(0);
// Read the first Byte of EEPROM that
for (int i = 1; i <= count; i++) {
// Loop once for each EEPROM entry
readID(i);
// Read an ID from EEPROM, it is stored in storedCard[4]
if (checkTwo(find, storedCard)) {
// Check to see if the storedCard read from EEPROM
return true;
break; // Stop looking we found it
} else {
// If not, return false
}
}
return false;
}
void readID(int number) {
int start = (number * 4) + 2;
// Figure out starting position
for (int i = 0; i < 4; i++) {
// Loop 4 times to get the 4 Bytes
storedCard[i] = EEPROM.read(start + i);
// Assign values read from EEPROM to array
}
}
void deleteID(byte a[]) {
if (!findID(a)) {
// Before we delete from the EEPROM, check to see if we have this card!
failedWrite(); // If not
} else {
int num = EEPROM.read(0);
// Get the numer of used spaces, position 0 stores the number of ID cards
int slot;
// Figure out the slot number of the card
int start;
// = (num * 4) + 6; // Figure out where the next slot starts
int looping;
// The number of times the loop repeats
int j;
int count = EEPROM.read(0);
// Read the first Byte of EEPROM that stores number of cards
slot = findIDSLOT(a);
//Figure out the slot number of the card to delete
start = (slot * 4) + 2;
looping = ((num - slot) * 4);
num--; // Decrement the counter by one
EEPROM.write(0, num); // Write the new count to the counter
for (j = 0; j < looping; j++) {
// Loop the card shift times
EEPROM.write(start + j, EEPROM.read(start + 4 + j));
// Shift the array values to 4 places earlier in the EEPROM
}
for (int k = 0; k < 4; k++) {
//Shifting loop
EEPROM.write(start + j + k, 0);
}
successDelete();
}
}
//For Failed to add the card:
void failedWrite() {
Serial.println("something wrong with Card");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("SOMETHING WRONG");
lcd.setCursor(0, 1);
lcd.print("WITH CARD");
delay(2000);
}
//For Sucessfully Deleted:
void successDelete() {
Serial.println("Succesfully removed");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("SUCCESFULLY");
lcd.setCursor(0, 1);
lcd.print("REMOVED CARD");
delay(2000);
}
int findIDSLOT(byte find[]) {
int count = EEPROM.read(0);
// Read the first Byte of EEPROM that
for (int i = 1; i <= count; i++) {
// Loop once for each EEPROM entry
readID(i);
// Read an ID from EEPROM, it is stored in storedCard[4]
if (checkTwo(find, storedCard)) {
// Check to see if the storedCard read from EEPROM
// is the same as the find[] ID card passed
return i;
// The slot number of the card
break;
// Stop looking we found it
}
}
}
//For Sucessfully Added:
void successWrite() {
Serial.println("Succesfully added");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("SUCCESFULLY");
lcd.setCursor(0, 1);
lcd.print("ADDED");
delay(2000);
}
//For Adding card to EEPROM:
void writeID(byte a[]) {
if (!findID(a)) {
// Before we write to the EEPROM, check to see if we have seen this card before!
int num = EEPROM.read(0);
// Get the numer of used spaces, position 0 stores the number of ID cards
int start = (num * 4) + 6;
// Figure out where the next slot starts
num++;
// Increment the counter by one
EEPROM.write(0, num);
// Write the new count to the counter
for (int j = 0; j < 4; j++) {
// Loop 4 times
EEPROM.write(start + j, a[j]);
// Write the array values to EEPROM in the right position
}
successWrite();
} else {
failedWrite();
}
}
void loop() {
lcd.clear();
lcd.setCursor(4, 0);
lcd.print("TAP YOUR");
lcd.setCursor(4, 1);
lcd.print("CARD HERE");
do {
successRead = getID(); // sets successRead to 1 when we get read from reader otherwise 0
if (programMode) {
// Program Mode cycles through RGB waiting to read a new card
} else {
}
}
while (!successRead);
//the program will not go further while you not get a successful read
if (programMode) {
if (isMaster(readCard)) {
//If master card scanned again exit program mode
Serial.println("This is ADMIN Card");
Serial.println("Exiting ADMIN Mode");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("EXITING FROM");
lcd.setCursor(0, 1);
lcd.print("ADMINISTRATOR MODE");
delay(2000);
programMode = false;
return;
} else {
if (findID(readCard)) {
//If scanned card is known delete it
Serial.println("I know this CARD, so removing");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("AVAILABLE!");
lcd.setCursor(0, 1);
lcd.print("SO DELETING.....");
delay(5000);
deleteID(readCard);
Serial.println("-----------------------------");
} else {
// If scanned card is not known add it
Serial.println("Adding this card...");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Card no:");
lcd.setCursor(0, 1);
lcd.print(readCard[0], HEX);
lcd.print(readCard[1], HEX);
lcd.print(readCard[2], HEX);
lcd.print(readCard[3], HEX);
lcd.print(readCard[4], HEX);
delay(4000);
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("NOT AVAILABLE");
lcd.setCursor(0, 1);
lcd.print("SO ADDING...");
delay(5000);
writeID(readCard);
Serial.println("-----------------------------");
}
}
} else {
if (isMaster(readCard)) {
// If scanned card's ID matches Master Card's ID enter program mode
programMode = true;
Serial.println("Welcome to Administrator Mode");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("WELCOME TO");
lcd.setCursor(0, 1);
lcd.print("ADMIN MODE");
delay(3000);
int count = EEPROM.read(0);
// Read the first Byte of EEPROM that
Serial.print("I have ");
// stores the number of ID's in EEPROM
Serial.print(count);
Serial.print(" record(s) on EEPROM");
Serial.println("");
Serial.println("Scan a card to ADD or REMOVE");
Serial.println("-----------------------------");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("SCAN CARD TO");
lcd.setCursor(0, 1);
lcd.print("ADD OR REMOVE...");
delay(2500);
} else {
if (findID(readCard)) {
// If not, see if the card is in the EEPROM
Serial.println("Acces Granted");
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("ACCESS GRANTED");
lcd.setCursor(0, 1);
lcd.print("YOU MAY ENTER NOW");
digitalWrite(8, HIGH);
delay(1500);
digitalWrite(8, LOW);
lcd.clear();
} else {
// If not, show that the ID was not valid
Serial.println("Access Denied");
for (int abcd = 0; abcd < 3; abcd++) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print(" SORRY");
lcd.setCursor(0, 1);
lcd.print(" ACCESS DENIED");
digitalWrite(8, HIGH);
delay(1000);
digitalWrite(8, LOW);
lcd.clear();
lcd.print(" YOU'RE NOT ");
lcd.setCursor(0, 1);
lcd.print(" AUTHORIZED ");
delay(1000);
}
lcd.clear();
}
}
}
}
Any help would be appreciated!