i want to write int value in rfid tag using rc522 module. i have a example of program to write string in rfid. but i getting difficulty to write int value. How to solve this issue?
#include <SPI.h>
#include <MFRC522.h>
#define SS_PIN 10
#define RST_PIN 9
MFRC522 mfrc522(SS_PIN, RST_PIN); // Create MFRC522 instance
MFRC522::StatusCode status; //variable to get card status
byte buffer[18]; //data transfer buffer (16+2 bytes data+CRC)
byte size = sizeof(buffer);
uint8_t pageAddr = 0x06; //In this example we will write/read 16 bytes (page 6,7,8 and 9).
//Ultraligth mem = 16 pages. 4 bytes per page.
//Pages 0 to 4 are for special functions.
void setup() {
Serial.begin(9600); // Initialize serial communications with the PC
SPI.begin(); // Init SPI bus
mfrc522.PCD_Init(); // Init MFRC522 card
Serial.println(F("Sketch has been started!"));
memcpy(buffer,"HELLO WORLD! ;-)",16);
}
void loop() {
// Look for new cards
if ( ! mfrc522.PICC_IsNewCardPresent())
return;
// Select one of the cards
if ( ! mfrc522.PICC_ReadCardSerial())
return;
// Write data ***********************************************
for (int i=0; i < 4; i++) {
//data is writen in blocks of 4 bytes (4 bytes per page)
status = (MFRC522::StatusCode) mfrc522.MIFARE_Ultralight_Write(pageAddr+i, &buffer[i*4], 4);
if (status != MFRC522::STATUS_OK) {
Serial.print(F("MIFARE_Read() failed: "));
Serial.println(mfrc522.GetStatusCodeName(status));
return;
}
}
Serial.println(F("MIFARE_Ultralight_Write() OK "));
Serial.println();
// Read data ***************************************************
Serial.println(F("Reading data ... "));
//data in 4 block is readed at once.
status = (MFRC522::StatusCode) mfrc522.MIFARE_Read(pageAddr, buffer, &size);
if (status != MFRC522::STATUS_OK) {
Serial.print(F("MIFARE_Read() failed: "));
Serial.println(mfrc522.GetStatusCodeName(status));
return;
}
Serial.print(F("Readed data: "));
//Dump a byte array to Serial
for (byte i = 0; i < 16; i++) {
Serial.write(buffer[i]);
}
Serial.println();
mfrc522.PICC_HaltA();
}