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如何在Arduino中获得RFID的UID?

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我有一个RFID-RC522(MF-RC522)模块,我正在使用Arduino草图程序 . 为了使用这种RFID,我下载了Arduino MFRC522库 .

我运行库的示例代码 .

这是代码 .

/*
 * MFRC522 - Library to use ARDUINO RFID MODULE KIT 13.56 MHZ WITH TAGS SPI W AND R BY COOQROBOT.
 * The library file MFRC522.h has a wealth of useful info. Please read it.
 * The functions are documented in MFRC522.cpp.
 *
 * Based on code Dr.Leong   ( WWW.B2CQSHOP.COM )
 * Created by Miguel Balboa (circuitito.com), Jan, 2012.
 * Rewritten by Søren Thing Andersen (access.thing.dk), fall of 2013 (Translation to English, refactored, comments, anti collision, cascade levels.)
 * Released into the public domain.
 *
 * Sample program showing how to read data from a PICC using a MFRC522 reader on the Arduino SPI interface.
 *----------------------------------------------------------------------------- empty_skull 
 * Aggiunti pin per arduino Mega
 * add pin configuration for arduino mega
 * http://mac86project.altervista.org/
 ----------------------------------------------------------------------------- Nicola Coppola
 * Pin layout should be as follows:
 * Signal     Pin              Pin               Pin
 *            Arduino Uno      Arduino Mega      MFRC522 board
 * ------------------------------------------------------------
 * Reset      9                5                 RST
 * SPI SS     10               53                SDA
 * SPI MOSI   11               51                MOSI
 * SPI MISO   12               50                MISO
 * SPI SCK    13               52                SCK
 *
 * The reader can be found on eBay for around 5 dollars. Search for "mf-rc522" on ebay.com. 
 */

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

#define SS_PIN 10
#define RST_PIN 9
MFRC522 mfrc522(SS_PIN, RST_PIN);   // Create MFRC522 instance.

void setup() {
    Serial.begin(9600); // Initialize serial communications with the PC
    SPI.begin();            // Init SPI bus
    mfrc522.PCD_Init(); // Init MFRC522 card
    Serial.println("Scan PICC to see UID and type...");
}

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));
}

当我运行此代码并将其中一张卡放入RFID阅读器时,很多信息显示在Arduino IDE的串行监视器上 . 像这样......(我无法发布图片)

//
Scan PICC to see UID and type...

Card UID : 84 90 6C A7

PICC type : MIFARE 1KB

Sector Block 0 1 2 3 4 5 6 7 ...

15     63   00 00 00 00 ...
//

但我需要的只是卡片UID . 这个案子是84 90 6C A7 .

实际上,我有项目 . 如果我放一张RFID卡,我想打开LED . 为此,我需要读取Card UID并将其分配给Arduino sketch程序中的某个变量 .

但我不知道在这种情况下如何获得RFID标签的UID(这个库和功能对我来说很复杂) .

如果有人知道如何做到这一点,请帮助我 .

4 回答

  • 6

    这是未经测试的代码,因为我现在没有Arduino . 我希望它有效 .

    用这样的方法替换示例中的DumpToSerial代码

    if (mfrc522.uid.uidByte[0] == 0x84 && mfrc522.uid.uidByte[1] == 0x90 && mfrc522.uid.uidByte[2] == 0x6c && mfrc522.uid.uidByte[3] == 0xa7) { // turn your LED on }

  • 1

    这是一个返回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;
    }
    

    像这样使用它:

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

    基于Thomas Matthews在_1666391中的回答 .

  • 6

    你可以通过这样做得到它:

    mfrc522.uid.uidByte
    

    它是一个字节[10]

  • 0

    我发现了另一种方式 .

    在图书馆 MFRC522.cpp 第1391行

    Serial.print(F("Card UID:"));
    
    for (byte i = 0; i < uid->size; i++)
    

    我在这个函数调用中创建了另一个函数: PICC_DumpDetailsToSerialUid(Uid *uid)

    看起来像:

    //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();
     }
    

    你可以把它放在你需要的任何地方,我只是把它放在大功能附近,知道它在哪里 .

    添加该功能后,您需要进入第409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 .

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

    如果你需要别的东西,你可以用其他功能做到这一点....祝你好运:)

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