读取卡号

#include <SPI.h>
#include <MFRC522.h>#define RST_PIN         9     // Reset pin of the module
#define SS_PIN          10    // Slave Select pin of the moduleMFRC522 rfid(SS_PIN, RST_PIN); // Create MFRC522 instancevoid setup() {Serial.begin(9600);SPI.begin(); // Init SPI busrfid.PCD_Init(); // Init MFRC522
}void loop() {if (rfid.PICC_IsNewCardPresent() && rfid.PICC_ReadCardSerial()) { // Check if new card is present and read its UID// Read the UID of the carduint8_t uidSize = rfid.uid.size;Serial.print("Card UID:");for (uint8_t i = 0; i < uidSize; i++) {Serial.print(rfid.uid.uidByte[i] < 0x10 ? " 0" : " ");Serial.print(rfid.uid.uidByte[i], HEX);}Serial.println();// Optionally, you could add this UID to an authorized list or perform other actions here.rfid.PICC_HaltA(); // Stop reading the cardrfid.PCD_StopCrypto1(); // Disable encryption on PCD}delay(100); // Short delay before re-checking for a card
}

判断是不是指定卡号

#include <SPI.h>
#include <MFRC522.h>#define RST_PIN         9     // Reset pin of the module
#define SS_PIN          10    // Slave Select pin of the module
#define LED_PIN         A0   // LED connected to digital pin 13MFRC522 rfid(SS_PIN, RST_PIN); // Create MFRC522 instance
boolean ledStatus = false; // LED status variablevoid setup() {Serial.begin(9600);SPI.begin();rfid.PCD_Init();pinMode(LED_PIN, OUTPUT); // Configure LED pin as output
}void loop() {if (rfid.PICC_IsNewCardPresent() && rfid.PICC_ReadCardSerial()) {// Read the UID of the carduint8_t uidSize = rfid.uid.size;String cardUID = "";for (uint8_t i = 0; i < uidSize; i++) {cardUID.concat(String(rfid.uid.uidByte[i], HEX));}if (cardUID.equalsIgnoreCase("90A94926")) { // Compare the read UID with the target UIDledStatus = true;digitalWrite(LED_PIN, HIGH); // Turn on the LEDSerial.println("Card UID: " + cardUID + ". LED turned ON.");} else {ledStatus = false;digitalWrite(LED_PIN, LOW); // Turn off the LED just in case it was previously on}rfid.PICC_HaltA();rfid.PCD_StopCrypto1();}// Keep the LED state even after the card is removeddigitalWrite(LED_PIN, ledStatus ? HIGH : LOW);delay(100); // Short delay before re-checking for a card
}