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Друзья помогите разобратсья как юзать функцию PCD_TransceiveData третий день не могу понять толком

Задача послать команду на смарт карту и получить ответ, но в backData пусто!

#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
  SPI.begin();                                         // Init SPI bus
  mfrc522.PCD_Init();                                  // Init MFRC522 card
  Serial.println(F("Awaiting you Card..."));           //shows in serial that it is ready to read
}
 
//*****************************************************************************************//
 
void loop() {
  if ( ! mfrc522.PICC_IsNewCardPresent()) {
    delay(50);
    return;
  }
byte sendData[20] = {0x00, 0xA4, 0x04, 0x00, 0x0e, 0x32, 0x50, 0x41, 0x59, 0x2e, 0x53, 0x59, 0x53, 0x2e, 0x44, 0x44, 0x46, 0x30, 0x31, 0x00};
byte sendLen = sizeof(sendData);
byte backData[255];
memset(backData,0,sizeof(backData));
byte backLen = sizeof(backData);
//*****************************************************************************************//
mfrc522.PCD_TransceiveData(sendData,sendLen,backData,backLen,NULL,0,false);
{
byte waitIRq = 0x30;    // RxIRq and IdleIRq
mfrc522.PCD_CommunicateWithPICC(mfrc522.PCD_Transceive, waitIRq, *sendData, sendLen, *backData, backLen, NULL,0,false);
}
for (byte i=0; i< sizeof(backData); i++){
  Serial.println(backData[i], HEX);
}
}
//*****************************************************************************************//