#include <SoftwareSerial.h>
#include <Wire.h>
#include <SPI.h>
#include <Adafruit_PN532.h>
 
#define DEBUG true
#define PN532_IRQ   (9) // (2)  <- changed to D9 for IRQ pin, refer to schematic
#define PN532_RESET (8) // (3)  <- changed to D8 for nReset pin, refer to schematic
 
SoftwareSerial esp8266(2,3); // make RX Arduino line is pin 2, make TX Arduino line is pin 3.
                             // This means that you need to connect the TX line from the esp to the Arduino's pin 2
                             // and the RX line from the esp to the Arduino's pin 3
Adafruit_PN532 nfc(PN532_IRQ, PN532_RESET);
#if defined(ARDUINO_ARCH_SAMD)
// for Zero, output on USB Serial console, remove line below if using
programming port to program the Zero!
// also change #define in Adafruit_PN532.cpp library file
   #define Serial SerialUSB
#endif
 
 
int a = 0;
void setup()
{
    #ifndef ESP8266
    while (!Serial); // for Leonardo/Micro/Zero
    #endif
  
  Serial.begin(9600);
  esp8266.begin(9600); // your esp's baud rate might be different
  nfc.begin();
  pinMode(11,OUTPUT);
  digitalWrite(11,LOW);
  
  pinMode(12,OUTPUT);
  digitalWrite(12,LOW);
 
  uint32_t versiondata = nfc.getFirmwareVersion();
    if (! versiondata)
    {
        Serial.print("\r\nDidn't find PN53x board");
        while (1); // halt
    }
 
      
  sendData("AT+RST\r\n",2000,DEBUG); // reset module
  sendData("AT+CWMODE=1\r\n",1000,DEBUG); // configure as access point
  sendData("AT+CIFSR\r\n",1000,DEBUG); // get ip address
  sendData("AT+CIPMUX=1\r\n",1000,DEBUG); // configure for multiple connections
  sendData("AT+CIPSERVER=1,80\r\n",1000,DEBUG); // turn on server on port 80
 
    // Got ok data, print it out!
    Serial.print("\r\nFound chip PN5");
    Serial.print((versiondata>>24) & 0xFF, HEX);
    Serial.print("\r\nFirmware ver. ");
    Serial.print((versiondata>>16) & 0xFF, DEC);
    Serial.print('.');
    Serial.print((versiondata>>8) & 0xFF, DEC);
 
 
   nfc.setPassiveActivationRetries(0xFF);
 
    // configure board to read RFID tags
 
    nfc.SAMConfig();
 
    Serial.print("\r\nWaiting for an ISO14443A card");
}
 
void loop()
{
    boolean success;
    uint8_t uid[] = { 0, 0, 0, 0, 0, 0, 0 };    // Buffer to store the returned UID
    uint8_t uidLength;              // Length of the UID (4 or 7 bytes depending on ISO14443A card type)
    success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, &uid[0], &uidLength);
 
    if (success)
    {
        Serial.print("\r\nFound a card!");
        Serial.print("\r\nUID Length: ");
        Serial.print(uidLength, DEC);
        Serial.print(" bytes");
        Serial.print("\r\nUID Value: ");
 
        
        if (a == 0){
        digitalWrite(11,HIGH);
        a = 1;
        }
        else {
          digitalWrite(11,LOW);
          a = 0;
        }
        
        Serial.println("LED2 on");
 
        for (uint8_t i = 0; i < uidLength; i++)
        {
            Serial.print(" 0x");
            Serial.print(uid[i], HEX);
        }
 
        // Wait 1 second before continuing
        delay(1000);
    }
 
  
  if(esp8266.available()) // check if the esp is sending a message 
  {
 
    
    if(esp8266.find("+IPD,"))
    {
         if(digitalRead(12) & a==1){ digitalWrite(12,LOW ); a=0; Serial.println("LED1 off"); }
    else if (a==0)             { digitalWrite(12,HIGH); a=1; Serial.println("LED1 on "); }
    delay(500); // wait for the serial buffer to fill up (read all the serial data)
    }
  }
 
  
}
 
/*
* Name: sendData
* Description: Function used to send data to ESP8266.
* Params: command - the data/command to send; timeout - the time to wait for a response; debug - print to Serial window?(true = yes, false = no)
* Returns: The response from the esp8266 (if there is a reponse)
*/
String sendData(String command, const int timeout, boolean debug)
{
    String response = "";
    
    esp8266.print(command); // send the read character to the esp8266
    
    long int time = millis();
    
    while( (time+timeout) > millis())
    {
      while(esp8266.available())
      {
        
        // The esp has data so display its output to the serial window 
        char c = esp8266.read(); // read the next character.
        response+=c;
      }  
    }
    
    if(debug)
    {
      Serial.print(response);
    }
    
    return response;
}
 
우노에서 esp8266 과 pin 532를 써서 WiFi와 NFC로 LED 2개를 각자 하나씩 on/off 하려는데요
 
NFC는 on/off가 잘되는데 WiFi는 신호를 보내면 수신했다가 NFC 태그 신호가 오면 on/off 가 됩니다.
 
다시말해 WiFi는 12번LED, NFC는 11번LED를 on/off하게 하고 싶은데
 
12번 LED는 WiFi 신호 + NFC 태그 여야 on/off됩니다.
 
​뭐가 문제인지 찾아보니 success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, &uid[0], &uidLength); 

부분이 문제인것 같습니다. 이 부분을 주석 처리 하면 WiFi로 12번 LED는 잘 되는데
 
이러면 문제는 nfc.readPassiveTargetID가 NFC 태그를 확인해서 토글시키는 역할이
 
라 NFC 11번 LED는 on/off가 불가능하지요.  어떡하면 좋을까요??