Cant' connect RFID RC522 with Arduino Leonardo

Hello, i am trying to connect and RC522 card on an Arduino Leonardo.
I tried some examples i found on internet like this one : RFID-RC522 With Arduino : 6 Steps - Instructables
or this one : How to wire RFID Card Reader - RC522 to Arduino Leonardo

but the only response I obtain from the basic RC522 program is "WARNING: Communication failure, is the MFRC522 properly connected?"

The only difference i got is that my card is a Bare Conductive Touch Board : Bare Conductive Touch Board - Boutique Semageek
100% based on an Arduino Leonardo

Did someone as the same problem ?
Thanks a lot for your help

Louis

Welcome to the forum

How exactly have you connected the reader to the Leonardo ? Which pins have you used ? Which serial interface of the Leonardo are you using ? Is it Serial or Serial1 ?

Please post your full sketch, using code tags when you do

In my experience the easiest way to tidy up the code and add the code tags is as follows

Start by tidying up your code by using Tools/Auto Format in the IDE to make it easier to read. Then use Edit/Copy for Forum and paste what was copied in a new reply. Code tags will have been added to the code to make it easy to read in the forum thus making it easier to provide help.

Hello,
The card is connectly exactly like this :

And the code is the dump info programm :

/*
 * ----------------------------------------------------------------------------
 * This is a MFRC522 library example; see https://github.com/miguelbalboa/rfid
 * for further details and other examples.
 * 
 * NOTE: The library file MFRC522.h has a lot of useful info. Please read it.
 * 
 * Released into the public domain.
 * ----------------------------------------------------------------------------
 * Example sketch/program showing how to read data from a PICC (that is: a RFID
 * Tag or Card) using a MFRC522 based RFID Reader on the Arduino SPI interface.
 * 
 * When the Arduino and the MFRC522 module are connected (see the pin layout
 * below), load this sketch into Arduino IDE then verify/compile and upload it.
 * To see the output: use Tools, Serial Monitor of the IDE (hit Ctrl+Shft+M).
 * When you present a PICC (that is: a RFID Tag or Card) at reading distance
 * of the MFRC522 Reader/PCD, the serial output will show the ID/UID, type and
 * any data blocks it can read. Note: you may see "Timeout in communication"
 * messages when removing the PICC from reading distance too early.
 * 
 * If your reader supports it, this sketch/program will read all the PICCs
 * presented (that is: multiple tag reading). So if you stack two or more
 * PICCs on top of each other and present them to the reader, it will first
 * output all details of the first and then the next PICC. Note that this
 * may take some time as all data blocks are dumped, so keep the PICCs at
 * reading distance until complete.
 * 
 * Typical pin layout used:
 * -----------------------------------------------------------------------------------------
 *             MFRC522      Arduino       Arduino   Arduino    Arduino          Arduino
 *             Reader/PCD   Uno           Mega      Nano v3    Leonardo/Micro   Pro Micro
 * Signal      Pin          Pin           Pin       Pin        Pin              Pin
 * -----------------------------------------------------------------------------------------
 * RST/Reset   RST          9             5         D9         RESET/ICSP-5     RST
 * SPI SS      SDA(SS)      10            53        D10        10               10
 * SPI MOSI    MOSI         11 / ICSP-4   51        D11        ICSP-4           16
 * SPI MISO    MISO         12 / ICSP-1   50        D12        ICSP-1           14
 * SPI SCK     SCK          13 / ICSP-3   52        D13        ICSP-3           15
 */

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

#define RST_PIN    9   // 
#define SS_PIN    10    //

MFRC522 mfrc522(SS_PIN, RST_PIN); // Create MFRC522 instance

void setup() {
  Serial.begin(9600);   // Initialize serial communications with the PC
  while (!Serial);    // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)
  SPI.begin();      // Init SPI bus
  mfrc522.PCD_Init();   // Init MFRC522
  ShowReaderDetails();  // Show details of PCD - MFRC522 Card Reader details
  Serial.println(F("Scan PICC to see UID, type, and data blocks..."));
}

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));
}

void ShowReaderDetails() {
  // Get the MFRC522 software version
  byte v = mfrc522.PCD_ReadRegister(mfrc522.VersionReg);
  Serial.print(F("MFRC522 Software Version: 0x"));
  Serial.print(v, HEX);
  if (v == 0x91)
    Serial.print(F(" = v1.0"));
  else if (v == 0x92)
    Serial.print(F(" = v2.0"));
  else
    Serial.print(F(" (unknown)"));
  Serial.println("");
  // When 0x00 or 0xFF is returned, communication probably failed
  if ((v == 0x00) || (v == 0xFF)) {
    Serial.println(F("WARNING: Communication failure, is the MFRC522 properly connected?"));
  }
}

Thanks you

Thank you for the update
The RC522 reader that you are using has an SPI interface so ignore my questions about the serial interface as they are not relevant

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