Problem with MFRC522 and relay

Other Hardware General Electronics
1

Hi everyone,

Thanks for your time. I'm quite a beginner.

I want to use an electronic lock with a relay, as the good RFID tag is detected.

I seem to have electrical problem or maybe it's my sketch :slight_smile:
Sometimes it works one time, sometimes it doesn't. I don't know why !! and it's frustrating

`Texte préformaté`#include <SPI.h>
#include <MFRC522.h>
// ecrire ici le numero UID du bon badge
const byte bonUID[4] = {119, 36, 198, 61};
//
const int relais = 4; // relais
const int pinRST = 9;  // pin RST du module RC522
const int pinSDA = 10; // pin SDA du module RC522
MFRC522 rfid(pinSDA, pinRST);
void setup()
{
  SPI.begin();
  rfid.PCD_Init();
  pinMode(relais, OUTPUT);
  digitalWrite(relais, LOW);

}
void loop()
{
  int refus = 0; // quand cette variable n'est pas nulle, c'est que le code est refusé
  if (rfid.PICC_IsNewCardPresent())  // on a dédecté un tag
  {
    if (rfid.PICC_ReadCardSerial())  // on a lu avec succès son contenu
    {
      for (byte i = 0; i < rfid.uid.size; i++) // comparaison avec le bon UID
      {
        if (rfid.uid.uidByte[i] != bonUID[i]) {
          refus++;
        }
      }


  
      if (refus == 0) // UID accepté
      {
        digitalWrite(relais, HIGH);
        delay(1000);
        digitalWrite(relais, LOW);

              // Re-Init RFID
  rfid.PICC_HaltA(); // Halt PICC
  rfid.PCD_StopCrypto1(); // Stop encryption on PCD


       
      }


      }
    }
  }`Texte préformaté`

c870d21b614e9166116ac5d9e21a12a0b0c5f7e2
c870d21b614e9166116ac5d9e21a12a0b0c5f7e22560Ă—1920 115 KB

Can you help me ?

2

for ( uint16_t i = 0; ...

-- or --

for ( int i = 0; ...

bottom line: whatever type rfid.uid.size should be the type of i

3

You think this is the problem ?

Because without the lock my relay works perfectly so i m wondering

5

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