Firmware ok, not reading cards

[skyguy126]

The wiring is correct I can assure you, connected based on the diagram inside the comments on every file. I have tried with and without a logic level converter on 3 different boards. One of the boards worked for a few minutes but stopped working after. The current board I have right now passes the firmware check but does not read any cards when running the dump info example.

Version is 0x92 and I am using a pro micro with a logic level converter. I have tried without as well and no luck.

Step 1: Describe your environment

• OS version: Win10
• Arduino IDE version: 1.8.5
• MFRC522 Library version: 1.4.0
• Arduino device: Pro Micro
• MFRC522 device: 3 different ones from different vendors

[Rotzbua]

@skyguy126 Did you solved your problem? Try a different tag, maybe your seller sent you some with wrong frequency.

[aeklo]

Experiencing exactly the same. Have tried multiple boards, separate power supply, shielding the SPI wires, clocking down SPI bus, hard reset/soft reset, extensive range of tags. By manipulating the MISO wire (pulling off/on), I sometimes manage to receive card dump. And strangely, then it is rock solid reading multiple tags simultaneously - until I reset the MCU. It has led me into debugging the SPI bus, but this could be rc522 settings, software or hardware. Anyone with any clues?

Edit: Also, some times it only reads one tag only. That is, two tags on top of each other gives no response - but some times it is able to read 3-4 tags stacked :-/

[ChrisLSaar]

Have the same problem.

Hardware: ESP8266 D1 mini, Sainsmart RC522, all connections soldert with short cable.

Sometimes it runs for hours, sometimes it reads only 2 times.

Firmwarecheck still ok.

No RFID Card is found.

[aeklo]

What I did, which miraculously solved my problem, was to edit a few settings. It turned out my board used non-inverting TX2-coil, effectively cancelling the TX1-coil with standard settings. Here is what I changed: mfrc522.PCD_WriteRegister(MFRC522::TxControlReg, 0x03); //Non-inverting TX2 mfrc522.PCD_WriteRegister(MFRC522::GsNReg, 0x44); //Also try FF mfrc522.PCD_WriteRegister(MFRC522::CWGsPReg, 0x0F); //Also try 3F mfrc522.PCD_WriteRegister(MFRC522::ModGsPReg, 0x0F); //Also try //3F

[x8973]

I join the question. Reading and writing registers is correct, but the PCD_communicateWithPICC() function returns STATUS_TIMEOUT. There is an interrupt from the timer RC522. The antenna tuning code above did not help.

OS version: Win10 1803 Arduino IDE version: None, Eclipse Neon + ESP32-IDF MFRC522 Library version: Latest, ported to ESP32-IDF Arduino device: Heltec ESP32 LoRa board MFRC522 device: RFID-RC522, Firmware 0x92

[x8973]

It turned out that the module has a very weak antenna. Sometimes it is possible to get a card, but reading the information from the card returns STATUS_TIMEOUT. How can I strengthen the antenna? Reading is produced as follows:

if (reader->PICC_isCardPresent())
{
    MFRC522::PICC_UID_t cardUid;
    printf("Card present\n");
    if (reader->PICC_readCardSerial(&cardUid))
    {
        // UID
        printf("Card UID:");
        for (uint8_t i = 0; i < cardUid.size; i++)
        {
            printf(" %02X", cardUid.uidByte[i]);
        }
        printf("\n");
    }
}

Sometimes "Card present" is displayed in the console, but PICC_readCardSerial() returns STATUS_TIMEOUT. Antenna adjustment:

void MFRC522::PCD_antennaOn()
{
    PCD_setRegisterBitMask(TxControlReg, 0x03);
    PCD_writeRegister(GsNReg, 0xFF); //Also try FF
    PCD_writeRegister(CWGsPReg, 0x3F); //Also try 3F
    PCD_writeRegister(ModGsPReg, 0x3F); //Also try //3F

    PCD_writeRegister(RFCfgReg, 0x0F);      //RxGain = 48dB
} // End PCD_antennaOn()

[aeklo]

Remember: Too high antenna gain may also prevent successful reading.

[rfranky]

Hello! Same problem here.

Sometimes it works for 1 week, sometimes only ours. After some success reads, the antena will not read any card anymore.

On this state (Not reading cards) I've tried a software resset of the arduino with no luck: void softwareReset() { asm volatile ( "jmp 0"); }

Board: Arduino nano rev3 MFRC522 device: RFID-RC522, Firmware 0x92 MFRC522 Library version: 1.3.6 IDE: Atom with PlatformIO

[x8973]

From my experience I can say that in case of such a hangup, the soft reset of the microcontroller does not help. It is necessary to reset the microcircuit MRFC522. I still achieved a steady reading of the serial number of the cards. I use the function of reading the serial number from another library, based on code Dr.Leong (WWW.B2CQSHOP.COM). I think that I will completely switch to it: it is simpler and it works. Now I'm working on adding the serial number rewriting functions to it.

[ChrisLSaar]

In my case I found the problem. With a new ESP it now works permanently. (14 days without problems). Seems to have been something wrong with the ESP. Maybe that's someone's problem, too. RC522 reads UID + data and writes new data every time I use it.

[x8973]

I would like details. What does "new ESP" mean?

[rfranky]

I've tryed with a software resset because it solved a similar problem: When i put two cards on the reader and try to read a mifare block status = (MFRC522::StatusCode) mfrc522.MIFARE_Read(blockAddress, block, &size); sometimes i get a status != MFRC522::STATUS_OK. And after that, without a softwareResset(), it doesen't read any more cards.

I've 12 RFID-RC522 (4 from amazon and 8 from alliexpress) trying to read cards 2 times per second 24/7. the 4 of amazon did not fail or hang never (2 months working 24/7). 3 from alliexpress have this fail (3 or 4 fails/hangs per week).

Today I've changed one of this "broken" RFID-RC522 for one from amazon.

Time will say if this is only a problem of a bad manufactured RFID-RC522.

[Rotzbua]

Can I close this? Seems the basic problem is (as usual) bad manufactured mfrc-boards... :disappointed:

[rfranky]

Yes. After 3 months still working well

[deybarmora]

Se que el foro esta cerrado, pero podría servirle a alguien en esta misma situación, así que aquí les comento mi experiencia: Tuve un problema similar con un modulo MFRC522 corriéndolo en un ESP32, la comunicación SPI estaba OK, con el detalle que cuando consultaba la ganancia del RFID con rfid.PCD_GetAntennaGain() me devolvía cero, esto me daba indicios que el modulo se comunica mas no se configuraba bien, entre ensayo y error agregue tres líneas de código en el setup() antes de ejecutar el rfid.PCD_Init(); y esto soluciono mi problema, parece que el problema es con el estado lógico del pin RST, mas no estoy seguro. a mi me funciono pero me gustaría saber el trasfondo del problema, si alguien lo descubre me comenta.

void setup(){

// se valida que RST_PIN este en nivel lógico bajo pinMode(RST_PIN, OUTPUT); digitalWrite(RST_PIN, LOW); delay(10);

// Inicia modulo lector MFRC522
rfid.PCD_Init();

/*

• 0x00 - 18 dB, mínimo
• 0x01 - 23 dB
• 0x02 - 18 dB, 010b es un duplicado para 000b
• 0x03 - 23 dB, 011b es un duplicado para 001b
• 0x04 - 33 dB, Por defecto en la librería
• 0x05 - 38 dB
• 0x06 - 43 dB

• 0x07 - 48 dB, máximo
  */ rfid.PCD_SetRegisterBitMask(rfid.RFCfgReg, (0x07<<4)); // Poner ganancia de RFID en 48dB, (valor máximo)

  Serial.print("Listo el Modulo RFID con ganancia = "); Serial.println(rfid.PCD_GetAntennaGain(),BIN); }