Processing those as you describe would be a very different proposition.įor the 4-byte scenario, I think you just need to convert the 4 byte values into a 32-bit long by shifting and adding the bytes in the right order. Is it only the 4-byte scenario that you need to deal with? The sketch you posted that some UIDs might be 7-byte values. Serial.println('Timed out waiting for a card') PN532 probably timed out waiting for a card turn the four byte UID of a mifare classic into a single variable #Ĭardidentifier <<= 8 cardidentifier |= uid Success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, &uid, &uidLength) if the uid is 4 bytes (Mifare Classic) or 7 bytes (Mifare Ultralight) 'uid' will be populated with the UID, and uidLength will indicate Wait for an ISO14443A type cards (Mifare, etc.). Uint8_t uidLength // Length of the UID (4 or 7 bytes depending on ISO14443A card type) Uint8_t uid = // Buffer to store the returned UID

Serial.println('Waiting for an ISO14443A card') This prevents us from waiting forever for a card, which is Set the max number of retry attempts to read from a card Serial.print('.') Serial.println((versiondata>8) & 0xFF, DEC) ') Serial.print((versiondata>16) & 0xFF, DEC) Serial.print('Found chip PN5') Serial.println((versiondata>24) & 0xFF, HEX) Uint32_t versiondata = nfc.getFirmwareVersion() Out the data and read from the card at the same time! Note that you need the baud rate to be 115200 because we need to print That can be used to determine what type of card it is. This example will attempt to connect to an ISO14443AĬard or tag and retrieve some basic information about it

Thank you for reading and any advice you may have to offer… I don’t think the modification would necessarily be too complicated if you know what you are doing, although I’m not qualified to make that assertion. Ideally I would like the serial monitor to just spit out this value rather than the reverse code, I know (I’m fairly sure) it can be done in code but unfortunately don’t have the ability (I’m really bad at maths), so was hoping somebody could come to my rescue… So, to get the correct UID you need to reverse this value (5A6E67CE) and then I have been using online converters etc to get the value I want (1517184974) It outputs a reverse HEX value on the serial monitor like so 0xCE 0圆7 0圆E 0x5A In its example library is a Mifare UID reading sketch.

Mifare change serial number