[Solved] Mega 2560 and RFID-NFC PN532 not working

Hi im new to Genuino and trying to get a Mega 2560 and RFID PN532 to work together.
Followed this guide Arduino Library | Adafruit PN532 RFID/NFC Breakout and Shield | Adafruit Learning System,
And running "read mifare" on the mega 2560.
But i only get 2 characters back on serial monitor, and no respons when holding a mifare rfid card in front of reader.
Busy lights constant red and power lights constant green.

Any tips on what i do wrong here?

Anyone?

Your serial port speeds are mismatched...
The sketch sets the speed to 115200, while the IDE is set to 9600

personally I was having some problems at 115200 so I compromised and set both speeds to 38400

Serial.begin(38400);

1 Like

Thanks. :slight_smile:
now i see hello.
But it can't find my pn532.

I have this setup.

USB Power from laptop.

Soldering wire:
Arduino side -> PN532 Side.

  1. 5V -> 5V
  2. GND -> GND
  3. A4 -> Analog in 4
  4. A5 -> Analog in 5
  5. PWM 2 -> Digital I/O 2

/**************************************************************************/
/*!
@file readMifare.pde
@author Adafruit Industries
@license BSD (see license.txt)

This example will wait for any ISO14443A card or tag, and
depending on the size of the UID will attempt to read from it.

If the card has a 4-byte UID it is probably a Mifare
Classic card, and the following steps are taken:

  • Authenticate block 4 (the first block of Sector 1) using
    the default KEYA of 0XFF 0XFF 0XFF 0XFF 0XFF 0XFF
  • If authentication succeeds, we can then read any of the
    4 blocks in that sector (though only block 4 is read here)

If the card has a 7-byte UID it is probably a Mifare
Ultralight card, and the 4 byte pages can be read directly.
Page 4 is read by default since this is the first 'general-
purpose' page on the tags.

This is an example sketch for the Adafruit PN532 NFC/RFID breakout boards
This library works with the Adafruit NFC breakout
----> PN532 NFC/RFID controller breakout board [v1.6] : ID 364 : $39.95 : Adafruit Industries, Unique & fun DIY electronics and kits

Check out the links above for our tutorials and wiring diagrams
These chips use SPI or I2C to communicate.

Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!

*/
/**************************************************************************/
#include <Wire.h>
#include <SPI.h>
#include <Adafruit_PN532.h>

// If using the breakout with SPI, define the pins for SPI communication.
#define PN532_SCK (2)
#define PN532_MOSI (3)
#define PN532_SS (4)
#define PN532_MISO (5)

// If using the breakout or shield with I2C, define just the pins connected
// to the IRQ and reset lines. Use the values below (2, 3) for the shield!
#define PN532_IRQ (2)
#define PN532_RESET (3) // Not connected by default on the NFC Shield

// Uncomment just one line below depending on how your breakout or shield
// is connected to the Arduino:

// Use this line for a breakout with a software SPI connection (recommended):
// Adafruit_PN532 nfc(PN532_SCK, PN532_MISO, PN532_MOSI, PN532_SS);

// Use this line for a breakout with a hardware SPI connection. Note that
// the PN532 SCK, MOSI, and MISO pins need to be connected to the Arduino's
// hardware SPI SCK, MOSI, and MISO pins. On an Arduino Uno these are
// SCK = 13, MOSI = 11, MISO = 12. The SS line can be any digital IO pin.
//Adafruit_PN532 nfc(PN532_SS);

// Or use this line for a breakout or shield with an I2C connection:
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

void setup(void) {
#ifndef ESP8266
while (!Serial); // for Leonardo/Micro/Zero
#endif
Serial.begin(38400);
Serial.println("Hello!");

nfc.begin();

uint32_t versiondata = nfc.getFirmwareVersion();
if (! versiondata) {
Serial.print("Didn't find PN53x board");
while (1); // halt
}
// Got ok data, print it out!
Serial.print("Found chip PN5"); Serial.println((versiondata>>24) & 0xFF, HEX);
Serial.print("Firmware ver. "); Serial.print((versiondata>>16) & 0xFF, DEC);
Serial.print('.'); Serial.println((versiondata>>8) & 0xFF, DEC);

// configure board to read RFID tags
nfc.SAMConfig();

Serial.println("Waiting for an ISO14443A Card ...");
}

void loop(void) {
uint8_t 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)

// Wait for an ISO14443A type cards (Mifare, etc.). When one is found
// 'uid' will be populated with the UID, and uidLength will indicate
// if the uid is 4 bytes (Mifare Classic) or 7 bytes (Mifare Ultralight)
success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, uid, &uidLength);

if (success) {
// Display some basic information about the card
Serial.println("Found an ISO14443A card");
Serial.print(" UID Length: ");Serial.print(uidLength, DEC);Serial.println(" bytes");
Serial.print(" UID Value: ");
nfc.PrintHex(uid, uidLength);
Serial.println("");

if (uidLength == 4)
{
// We probably have a Mifare Classic card ...
Serial.println("Seems to be a Mifare Classic card (4 byte UID)");

// Now we need to try to authenticate it for read/write access
// Try with the factory default KeyA: 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF
Serial.println("Trying to authenticate block 4 with default KEYA value");
uint8_t keya[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

// Start with block 4 (the first block of sector 1) since sector 0
// contains the manufacturer data and it's probably better just
// to leave it alone unless you know what you're doing
success = nfc.mifareclassic_AuthenticateBlock(uid, uidLength, 4, 0, keya);

if (success)
{
Serial.println("Sector 1 (Blocks 4..7) has been authenticated");
uint8_t data[16];

// If you want to write something to block 4 to test with, uncomment
// the following line and this text should be read back in a minute
//memcpy(data, (const uint8_t[]){ 'a', 'd', 'a', 'f', 'r', 'u', 'i', 't', '.', 'c', 'o', 'm', 0, 0, 0, 0 }, sizeof data);
// success = nfc.mifareclassic_WriteDataBlock (4, data);

// Try to read the contents of block 4
success = nfc.mifareclassic_ReadDataBlock(4, data);

if (success)
{
// Data seems to have been read ... spit it out
Serial.println("Reading Block 4:");
nfc.PrintHexChar(data, 16);
Serial.println("");

// Wait a bit before reading the card again
delay(1000);
}
else
{
Serial.println("Ooops ... unable to read the requested block. Try another key?");
}
}
else
{
Serial.println("Ooops ... authentication failed: Try another key?");
}
}

if (uidLength == 7)
{
// We probably have a Mifare Ultralight card ...
Serial.println("Seems to be a Mifare Ultralight tag (7 byte UID)");

// Try to read the first general-purpose user page (#4)
Serial.println("Reading page 4");
uint8_t data[32];
success = nfc.mifareultralight_ReadPage (4, data);
if (success)
{
// Data seems to have been read ... spit it out
nfc.PrintHexChar(data, 4);
Serial.println("");

// Wait a bit before reading the card again
delay(1000);
}
else
{
Serial.println("Ooops ... unable to read the requested page!?");
}
}
}
}

ok. found the fault. :slight_smile:

Had to move Analog 4 and 5 over to Com 20 and 21 (SDA-SCL).

drefts:
ok. found the fault. :slight_smile:

Had to move Analog 4 and 5 over to Com 20 and 21 (SDA-SCL).

have you solved the problem, because i have the same problem like you, the Serial Monitor Shown
"Didn't find the PN53X board"
can you help me....
thanks

Hi guys! my english is not so good. I was looking and looking, for the same error message, and was not working for many hours. And after that, i saw that the pn532 has a very little switch that have to change to the correct SPI, I2C or HSU combination. For default it brings to HSU, if you want to communicate with SPI or I2C, you must to change it!!!
I hope this can help some of you guys!!!!!!!!!

hmm