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@vongomben
Last active December 3, 2020 11:28
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Mifare Casting Code into String [FN]
/**************************************************************************/
/*!
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.
To enable debug message, define DEBUG in PN532/PN532_debug.h
*/
/**************************************************************************/
#if 0
#include <SPI.h>
#include <PN532_SPI.h>
#include "PN532.h"
PN532_SPI pn532spi(SPI, 10);
PN532 nfc(pn532spi);
#elif 1
#include <PN532_HSU.h>
#include <PN532.h>
PN532_HSU pn532hsu(Serial1);
PN532 nfc(pn532hsu);
#else
#include <Wire.h>
#include <PN532_I2C.h>
#include <PN532.h>
PN532_I2C pn532i2c(Wire);
PN532 nfc(pn532i2c);
#endif
void setup(void) {
Serial.begin(115200);
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(uid[0], DEC);
Serial.println(uid[0], HEX);
Serial.println("");
if (uidLength == 4)
{
// Code to String
String code = String(uid[0]);
code += String(uid[1]);
code += String(uid[2]);
code += String(uid[3]);
Serial.print("code = ");
Serial.print(code);
Serial.println(" - - - - - ");
// 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
// data = { 'a', 'd', 'a', 'f', 'r', 'u', 'i', 't', '.', 'c', 'o', 'm', 0, 0, 0, 0};
// 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)
{
// Code to String
String code = String(uid[0]);
code += String(uid[1]);
code += String(uid[2]);
code += String(uid[3]);
code += String(uid[4]);
code += String(uid[5]);
code += String(uid[6]);
Serial.print("code = ");
Serial.print(code);
Serial.println(" - - - - - ");
// 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!?");
}
}
}
}
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