Arduino + RFID 读取 IC 卡 Arduino uno中获得RFID的UID 并通过串口转发RFID卡号

RFID简介：射频识别即RFID（Radio Frequency IDentification）技术，又称无线射频识别，是一种通信技术，可通过无线电讯号识别特定目标并读写相关数据，而无需识别系统与特定目标之间建立机械或光学接触。常用的有低频（125k~134.2K）、高频（13.56Mhz）、超高频，微波等技术。RFID读写器也分移动式的和固定式的，目前RFID技术应用很广，如：图书馆，门禁系统，食品安全溯源等。

硬件准备

（基于Arduino的开发板、MFRC522读卡器模块）

Arduino Uno * 1



RFID-RC522 模块 * 1



IC卡 * 1-2



RFID技术现在都非常成熟和应用广泛，今天我们就来看看这个RFID如何实现读取里面的数据

接线

Arduino Uno <—> RFID-RC522

10 <—> SDA

13 <—> SCK

11 <—> MOSI

12 <—> MISO

null <—> IRQ

GND <—> GND

9 <—> RST

3.3V <—> 3.3V

需要用到RFID-RC522的库

法一、下载：https://github.com/miguelbalboa/rfid

下载解压到Arduino IDE的安装路径里的库文件夹libraries

https://download.csdn.net/download/v86337286/11813061

法二、点开管理库，在搜索栏里输入RC522，找到图中的库，





点击安装（我这图是已经安装过）

示例代码 .

Arduino + RFID 读取 IC 卡信息

读取 IC 卡信息后并通过串口将卡号及0扇区卡号数据打印出来，其他15个扇区不显示扇区内容

代码如下

/*
 * --------------------------------------------------------------------------------------------------------------------
 * Example sketch/program showing how to read data from a PICC to serial.
 * --------------------------------------------------------------------------------------------------------------------
 * This is a MFRC522 library example; for further details and other examples see: https://github.com/miguelbalboa/rfid
 *
 * Example sketch/program showing how to read data from a PICC (that is: a RFID Tag or Card) using a MFRC522 based RFID
 * Reader on the Arduino SPI interface.
 *
 * When the Arduino and the MFRC522 module are connected (see the pin layout below), load this sketch into Arduino IDE
 * then verify/compile and upload it. To see the output: use Tools, Serial Monitor of the IDE (hit Ctrl+Shft+M). When
 * you present a PICC (that is: a RFID Tag or Card) at reading distance of the MFRC522 Reader/PCD, the serial output
 * will show the ID/UID, type and any data blocks it can read. Note: you may see "Timeout in communication" messages
 * when removing the PICC from reading distance too early.
 *
 * If your reader supports it, this sketch/program will read all the PICCs presented (that is: multiple tag reading).
 * So if you stack two or more PICCs on top of each other and present them to the reader, it will first output all
 * details of the first and then the next PICC. Note that this may take some time as all data blocks are dumped, so
 * keep the PICCs at reading distance until complete.
 *
 * @license Released into the public domain.
 *
 * Typical pin layout used:
 * -----------------------------------------------------------------------------------------
 *             MFRC522      Arduino       Arduino   Arduino    Arduino          Arduino
 *             Reader/PCD   Uno/101       Mega      Nano v3    Leonardo/Micro   Pro Micro
 * Signal      Pin          Pin           Pin       Pin        Pin              Pin
 * -----------------------------------------------------------------------------------------
 * RST/Reset   RST          9             5         D9         RESET/ICSP-5     RST
 * SPI SS      SDA(SS)      10            53        D10        10               10
 * SPI MOSI    MOSI         11 / ICSP-4   51        D11        ICSP-4           16
 * SPI MISO    MISO         12 / ICSP-1   50        D12        ICSP-1           14
 * SPI SCK     SCK          13 / ICSP-3   52        D13        ICSP-3           15
 */

#include <SPI.h>
#include <MFRC522.h>

#define RST_PIN         9          // Configurable, see typical pin layout above
#define SS_PIN          10         // Configurable, see typical pin layout above

MFRC522 mfrc522(SS_PIN, RST_PIN);  // Create MFRC522 instance

void setup() {
    Serial.begin(9600);     // Initialize serial communications with the PC
    while (!Serial);        // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)
    SPI.begin();            // Init SPI bus
    mfrc522.PCD_Init();     // Init MFRC522
    mfrc522.PCD_DumpVersionToSerial();  // Show details of PCD - MFRC522 Card Reader details
    Serial.println(F("Scan PICC to see UID, SAK, type, and data blocks..."));
}

void loop() {
    // Look for new cards
    if ( ! mfrc522.PICC_IsNewCardPresent()) {
        return;
    }

    // Select one of the cards
    if ( ! mfrc522.PICC_ReadCardSerial()) {
        return;
    }

    // Dump debug info about the card; PICC_HaltA() is automatically called
    mfrc522.PICC_DumpToSerial(&(mfrc522.uid));
}

运行此代码并将其中一张卡放入RFID卡时，很多信息显示在Arduino IDE的串行监视器上

看完了上面那如何在Arduino中获得RFID的UID？

Arduino uno中只获得RFID的UID 并通过串口转发

法一

创建了另一个函数： PICC_DumpDetailsToSerialUid(Uid *uid)

函数如下

//This is just for read UID!

void MFRC522::PICC_DumpDetailsToSerialUid(Uid *uid){

Serial.print(F(“Card JUST UID :”));

for (byte i = 0; i < uid->size; i++) {

if(uid->uidByte[i] < 0x10)

Serial.print(F(" 0"));

else

Serial.print(F(" "));

Serial.print(uid->uidByte[i], HEX);

}

Serial.println();

}

可以把它放在你需要的任何地方

示例：



添加该功能后，您需要进入第410行的 MFRC522.h 库并添加

void PICC_DumpDetailsToSerialUid(Uid *uid);

在该库中进行了这两次编辑后，您可以在任意位置调用该函数 .

示例：



用Arduino调用它： mfrc522.PICC_DumpDetailsToSerialUid(&(mfrc522.uid)); 只仅且只有一个函数用于uid读取

效果

法二

返回UID的函数 .

/**
 * mfrc522.PICC_IsNewCardPresent() should be checked before
 * @return the card UID
 */
unsigned long getID(){
  if ( ! mfrc522.PICC_ReadCardSerial()) { //Since a PICC placed get Serial and continue
    return -1;
  }
  unsigned long hex_num;
  hex_num =  mfrc522.uid.uidByte[0] << 24;
  hex_num += mfrc522.uid.uidByte[1] << 16;
  hex_num += mfrc522.uid.uidByte[2] <<  8;
  hex_num += mfrc522.uid.uidByte[3];
  mfrc522.PICC_HaltA(); // Stop reading
  return hex_num;
}

例如这样使用：

if(mfrc522.PICC_IsNewCardPresent()) {
  unsigned long uid = getID();
  if(uid != -1){
    Serial.print("Card detected, UID: "); Serial.println(uid);
  }
}