# SPDX-FileCopyrightText: 2015-2018 Tony DiCola for Adafruit Industries # # SPDX-License-Identifier: MIT """ ``adafruit_pn532`` ==================================================== This module will let you communicate with a PN532 RFID/NFC shield or breakout using I2C, SPI or UART. * Author(s): Original Raspberry Pi code by Tony DiCola, CircuitPython by ladyada Implementation Notes -------------------- **Hardware:** * Adafruit `PN532 Breakout `_ * Adafruit `PN532 Shield `_ **Software and Dependencies:** * Adafruit CircuitPython firmware for the supported boards: https://github.com/adafruit/circuitpython/releases * Adafruit's Bus Device library: https://github.com/adafruit/Adafruit_CircuitPython_BusDevice """ import time from digitalio import Direction from micropython import const try: from typing import Optional, Tuple, Union from typing_extensions import Literal from circuitpython_typing import ReadableBuffer from digitalio import DigitalInOut # pylint: disable=ungrouped-imports except ImportError: pass __version__ = "0.0.0+auto.0" __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_PN532.git" _PREAMBLE = const(0x00) _STARTCODE1 = const(0x00) _STARTCODE2 = const(0xFF) _POSTAMBLE = const(0x00) _HOSTTOPN532 = const(0xD4) _PN532TOHOST = const(0xD5) # PN532 Commands _COMMAND_DIAGNOSE = const(0x00) _COMMAND_GETFIRMWAREVERSION = const(0x02) _COMMAND_GETGENERALSTATUS = const(0x04) _COMMAND_READREGISTER = const(0x06) _COMMAND_WRITEREGISTER = const(0x08) _COMMAND_READGPIO = const(0x0C) _COMMAND_WRITEGPIO = const(0x0E) _COMMAND_SETSERIALBAUDRATE = const(0x10) _COMMAND_SETPARAMETERS = const(0x12) _COMMAND_SAMCONFIGURATION = const(0x14) _COMMAND_POWERDOWN = const(0x16) _COMMAND_RFCONFIGURATION = const(0x32) _COMMAND_RFREGULATIONTEST = const(0x58) _COMMAND_INJUMPFORDEP = const(0x56) _COMMAND_INJUMPFORPSL = const(0x46) _COMMAND_INLISTPASSIVETARGET = const(0x4A) _COMMAND_INATR = const(0x50) _COMMAND_INPSL = const(0x4E) _COMMAND_INDATAEXCHANGE = const(0x40) _COMMAND_INCOMMUNICATETHRU = const(0x42) _COMMAND_INDESELECT = const(0x44) _COMMAND_INRELEASE = const(0x52) _COMMAND_INSELECT = const(0x54) _COMMAND_INAUTOPOLL = const(0x60) _COMMAND_TGINITASTARGET = const(0x8C) _COMMAND_TGSETGENERALBYTES = const(0x92) _COMMAND_TGGETDATA = const(0x86) _COMMAND_TGSETDATA = const(0x8E) _COMMAND_TGSETMETADATA = const(0x94) _COMMAND_TGGETINITIATORCOMMAND = const(0x88) _COMMAND_TGRESPONSETOINITIATOR = const(0x90) _COMMAND_TGGETTARGETSTATUS = const(0x8A) _RESPONSE_INDATAEXCHANGE = const(0x41) _RESPONSE_INLISTPASSIVETARGET = const(0x4B) _WAKEUP = const(0x55) _MIFARE_ISO14443A = const(0x00) # Mifare Commands MIFARE_CMD_AUTH_A = const(0x60) MIFARE_CMD_AUTH_B = const(0x61) MIFARE_CMD_READ = const(0x30) MIFARE_CMD_WRITE = const(0xA0) MIFARE_CMD_TRANSFER = const(0xB0) MIFARE_CMD_DECREMENT = const(0xC0) MIFARE_CMD_INCREMENT = const(0xC1) MIFARE_CMD_STORE = const(0xC2) MIFARE_ULTRALIGHT_CMD_WRITE = const(0xA2) # Prefixes for NDEF Records (to identify record type) NDEF_URIPREFIX_NONE = const(0x00) NDEF_URIPREFIX_HTTP_WWWDOT = const(0x01) NDEF_URIPREFIX_HTTPS_WWWDOT = const(0x02) NDEF_URIPREFIX_HTTP = const(0x03) NDEF_URIPREFIX_HTTPS = const(0x04) NDEF_URIPREFIX_TEL = const(0x05) NDEF_URIPREFIX_MAILTO = const(0x06) NDEF_URIPREFIX_FTP_ANONAT = const(0x07) NDEF_URIPREFIX_FTP_FTPDOT = const(0x08) NDEF_URIPREFIX_FTPS = const(0x09) NDEF_URIPREFIX_SFTP = const(0x0A) NDEF_URIPREFIX_SMB = const(0x0B) NDEF_URIPREFIX_NFS = const(0x0C) NDEF_URIPREFIX_FTP = const(0x0D) NDEF_URIPREFIX_DAV = const(0x0E) NDEF_URIPREFIX_NEWS = const(0x0F) NDEF_URIPREFIX_TELNET = const(0x10) NDEF_URIPREFIX_IMAP = const(0x11) NDEF_URIPREFIX_RTSP = const(0x12) NDEF_URIPREFIX_URN = const(0x13) NDEF_URIPREFIX_POP = const(0x14) NDEF_URIPREFIX_SIP = const(0x15) NDEF_URIPREFIX_SIPS = const(0x16) NDEF_URIPREFIX_TFTP = const(0x17) NDEF_URIPREFIX_BTSPP = const(0x18) NDEF_URIPREFIX_BTL2CAP = const(0x19) NDEF_URIPREFIX_BTGOEP = const(0x1A) NDEF_URIPREFIX_TCPOBEX = const(0x1B) NDEF_URIPREFIX_IRDAOBEX = const(0x1C) NDEF_URIPREFIX_FILE = const(0x1D) NDEF_URIPREFIX_URN_EPC_ID = const(0x1E) NDEF_URIPREFIX_URN_EPC_TAG = const(0x1F) NDEF_URIPREFIX_URN_EPC_PAT = const(0x20) NDEF_URIPREFIX_URN_EPC_RAW = const(0x21) NDEF_URIPREFIX_URN_EPC = const(0x22) NDEF_URIPREFIX_URN_NFC = const(0x23) _GPIO_VALIDATIONBIT = const(0x80) _GPIO_P30 = const(0) _GPIO_P31 = const(1) _GPIO_P32 = const(2) _GPIO_P33 = const(3) _GPIO_P34 = const(4) _GPIO_P35 = const(5) _ACK = b"\x00\x00\xFF\x00\xFF\x00" _FRAME_START = b"\x00\x00\xFF" class BusyError(Exception): """Base class for exceptions in this module.""" class PN532: """PN532 driver base, must be extended for I2C/SPI/UART interfacing""" def __init__( self, *, debug: bool = False, irq: Optional[DigitalInOut] = None, reset: Optional[DigitalInOut] = None, ) -> None: """Create an instance of the PN532 class""" self.low_power = True self.debug = debug self._irq = irq self._reset_pin = reset self.reset() _ = self.firmware_version def _read_data(self, count: int) -> Union[bytes, bytearray]: # Read raw data from device, not including status bytes: # Subclasses MUST implement this! raise NotImplementedError def _write_data(self, framebytes: bytes) -> None: # Write raw bytestring data to device, not including status bytes: # Subclasses MUST implement this! raise NotImplementedError def _wait_ready(self, timeout: float) -> bool: # Check if busy up to max length of 'timeout' seconds # Subclasses MUST implement this! raise NotImplementedError def _wakeup(self) -> None: # Send special command to wake up raise NotImplementedError def reset(self) -> None: """Perform a hardware reset toggle and then wake up the PN532""" if self._reset_pin: if self.debug: print("Resetting") self._reset_pin.direction = Direction.OUTPUT self._reset_pin.value = False time.sleep(0.1) self._reset_pin.value = True time.sleep(0.1) self._wakeup() def _write_frame(self, data: bytearray) -> None: """Write a frame to the PN532 with the specified data bytearray.""" assert ( data is not None and 1 < len(data) < 255 ), "Data must be array of 1 to 255 bytes." # Build frame to send as: # - Preamble (0x00) # - Start code (0x00, 0xFF) # - Command length (1 byte) # - Command length checksum # - Command bytes # - Checksum # - Postamble (0x00) length = len(data) frame = bytearray(length + 8) frame[0] = _PREAMBLE frame[1] = _STARTCODE1 frame[2] = _STARTCODE2 checksum = sum(frame[0:3]) frame[3] = length & 0xFF frame[4] = (~length + 1) & 0xFF frame[5:-2] = data checksum += sum(data) frame[-2] = ~checksum & 0xFF frame[-1] = _POSTAMBLE # Send frame. if self.debug: print("Write frame: ", [hex(i) for i in frame]) self._write_data(bytes(frame)) def _read_frame(self, length: int) -> Union[bytes, bytearray]: """Read a response frame from the PN532 of at most length bytes in size. Returns the data inside the frame if found, otherwise raises an exception if there is an error parsing the frame. Note that less than length bytes might be returned! """ # Read frame with expected length of data. response = self._read_data(length + 7) if self.debug: print("Read frame:", [hex(i) for i in response]) # Swallow all the 0x00 values that preceed 0xFF. offset = 0 while response[offset] == 0x00: offset += 1 if offset >= len(response): raise RuntimeError("Response frame preamble does not contain 0x00FF!") if response[offset] != 0xFF: raise RuntimeError("Response frame preamble does not contain 0x00FF!") offset += 1 if offset >= len(response): raise RuntimeError("Response contains no data!") # Check length & length checksum match. frame_len = response[offset] if (frame_len + response[offset + 1]) & 0xFF != 0: raise RuntimeError("Response length checksum did not match length!") # Check frame checksum value matches bytes. checksum = sum(response[offset + 2 : offset + 2 + frame_len + 1]) & 0xFF if checksum != 0: raise RuntimeError( "Response checksum did not match expected value: ", checksum ) # Return frame data. return response[offset + 2 : offset + 2 + frame_len] def call_function( self, command: int, response_length: int = 0, params: ReadableBuffer = b"", timeout: float = 1, ) -> Optional[Union[bytes, bytearray]]: """Send specified command to the PN532 and expect up to response_length bytes back in a response. Note that less than the expected bytes might be returned! Params can optionally specify an array of bytes to send as parameters to the function call. Will wait up to timeout seconds for a response and return a bytearray of response bytes, or None if no response is available within the timeout. """ if not self.send_command(command, params=params, timeout=timeout): return None return self.process_response( command, response_length=response_length, timeout=timeout ) def send_command( self, command: int, params: ReadableBuffer = b"", timeout: float = 1 ) -> bool: """Send specified command to the PN532 and wait for an acknowledgment. Will wait up to timeout seconds for the acknowledgment and return True. If no acknowledgment is received, False is returned. """ if self.low_power: self._wakeup() # Build frame data with command and parameters. data = bytearray(2 + len(params)) data[0] = _HOSTTOPN532 data[1] = command & 0xFF for i, val in enumerate(params): data[2 + i] = val # Send frame and wait for response. try: self._write_frame(data) except OSError: return False if not self._wait_ready(timeout): return False # Verify ACK response and wait to be ready for function response. if not _ACK == self._read_data(len(_ACK)): raise RuntimeError("Did not receive expected ACK from PN532!") return True def process_response( self, command: int, response_length: int = 0, timeout: float = 1 ) -> Optional[Union[bytes, bytearray]]: """Process the response from the PN532 and expect up to response_length bytes back in a response. Note that less than the expected bytes might be returned! Will wait up to timeout seconds for a response and return a bytearray of response bytes, or None if no response is available within the timeout. """ if not self._wait_ready(timeout): return None # Read response bytes. response = self._read_frame(response_length + 2) # Check that response is for the called function. if not (response[0] == _PN532TOHOST and response[1] == (command + 1)): raise RuntimeError("Received unexpected command response!") # Return response data. return response[2:] def power_down(self) -> bool: """Put the PN532 into a low power state. If the reset pin is connected a hard power down is performed, if not, a soft power down is performed instead. Returns True if the PN532 was powered down successfully or False if not.""" if self._reset_pin: # Hard Power Down if the reset pin is connected self._reset_pin.value = False self.low_power = True else: # Soft Power Down otherwise. Enable wakeup on I2C, SPI, UART response = self.call_function(_COMMAND_POWERDOWN, params=[0xB0, 0x00]) self.low_power = response[0] == 0x00 time.sleep(0.005) return self.low_power @property def firmware_version(self) -> Tuple[int, int, int, int]: """Call PN532 GetFirmwareVersion function and return a tuple with the IC, Ver, Rev, and Support values. """ response = self.call_function(_COMMAND_GETFIRMWAREVERSION, 4, timeout=0.5) if response is None: raise RuntimeError("Failed to detect the PN532") return tuple(response) def SAM_configuration(self) -> None: # pylint: disable=invalid-name """Configure the PN532 to read MiFare cards.""" # Send SAM configuration command with configuration for: # - 0x01, normal mode # - 0x14, timeout 50ms * 20 = 1 second # - 0x01, use IRQ pin # Note that no other verification is necessary as call_function will # check the command was executed as expected. self.call_function(_COMMAND_SAMCONFIGURATION, params=[0x01, 0x14, 0x01]) def read_passive_target( self, card_baud: int = _MIFARE_ISO14443A, timeout: float = 1 ) -> Optional[bytearray]: """Wait for a MiFare card to be available and return its UID when found. Will wait up to timeout seconds and return None if no card is found, otherwise a bytearray with the UID of the found card is returned. """ # Send passive read command for 1 card. Expect at most a 7 byte UUID. response = self.listen_for_passive_target(card_baud=card_baud, timeout=timeout) # If no response is available return None to indicate no card is present. if not response: return None return self.get_passive_target(timeout=timeout) def listen_for_passive_target( self, card_baud: int = _MIFARE_ISO14443A, timeout: float = 1 ) -> bool: """Send command to PN532 to begin listening for a Mifare card. This returns True if the command was received successfully. Note, this does not also return the UID of a card! `get_passive_target` must be called to read the UID when a card is found. If just looking to see if a card is currently present use `read_passive_target` instead. """ # Send passive read command for 1 card. Expect at most a 7 byte UUID. try: response = self.send_command( _COMMAND_INLISTPASSIVETARGET, params=[0x01, card_baud], timeout=timeout ) except BusyError: return False # _COMMAND_INLISTPASSIVETARGET failed return response def get_passive_target( self, timeout: float = 1 ) -> Optional[Union[bytes, bytearray]]: """Will wait up to timeout seconds and return None if no card is found, otherwise a bytearray with the UID of the found card is returned. `listen_for_passive_target` must have been called first in order to put the PN532 into a listening mode. It can be useful to use this when using the IRQ pin. Use the IRQ pin to detect when a card is present and then call this function to read the card's UID. This reduces the amount of time spend checking for a card. """ response = self.process_response( _COMMAND_INLISTPASSIVETARGET, response_length=30, timeout=timeout ) # If no response is available return None to indicate no card is present. if response is None: return None # Check only 1 card with up to a 7 byte UID is present. if response[0] != 0x01: raise RuntimeError("More than one card detected!") if response[5] > 7: raise RuntimeError("Found card with unexpectedly long UID!") # Return UID of card. return response[6 : 6 + response[5]] def mifare_classic_authenticate_block( # pylint: disable=invalid-name self, uid: ReadableBuffer, block_number: int, key_number: Literal[0x60, 0x61], key: ReadableBuffer, ) -> bool: """Authenticate specified block number for a MiFare classic card. Uid should be a byte array with the UID of the card, block number should be the block to authenticate, key number should be the key type (like MIFARE_CMD_AUTH_A or MIFARE_CMD_AUTH_B), and key should be a byte array with the key data. Returns True if the block was authenticated, or False if not authenticated. """ # Build parameters for InDataExchange command to authenticate MiFare card. uidlen = len(uid) keylen = len(key) params = bytearray(3 + uidlen + keylen) params[0] = 0x01 # Max card numbers params[1] = key_number & 0xFF params[2] = block_number & 0xFF params[3 : 3 + keylen] = key params[3 + keylen :] = uid # Send InDataExchange request and verify response is 0x00. response = self.call_function( _COMMAND_INDATAEXCHANGE, params=params, response_length=1 ) return response[0] == 0x00 def mifare_classic_read_block( self, block_number: int ) -> Optional[Union[bytes, bytearray]]: """Read a block of data from the card. Block number should be the block to read. If the block is successfully read a bytearray of length 16 with data starting at the specified block will be returned. If the block is not read then None will be returned. """ # Send InDataExchange request to read block of MiFare data. response = self.call_function( _COMMAND_INDATAEXCHANGE, params=[0x01, MIFARE_CMD_READ, block_number & 0xFF], response_length=17, ) # Check first response is 0x00 to show success. if response[0] != 0x00: return None # Return first 4 bytes since 16 bytes are always returned. return response[1:] def mifare_classic_write_block( self, block_number: int, data: ReadableBuffer ) -> bool: """Write a block of data to the card. Block number should be the block to write and data should be a byte array of length 16 with the data to write. If the data is successfully written then True is returned, otherwise False is returned. """ assert ( data is not None and len(data) == 16 ), "Data must be an array of 16 bytes!" # Build parameters for InDataExchange command to do MiFare classic write. params = bytearray(19) params[0] = 0x01 # Max card numbers params[1] = MIFARE_CMD_WRITE params[2] = block_number & 0xFF params[3:] = data # Send InDataExchange request. response = self.call_function( _COMMAND_INDATAEXCHANGE, params=params, response_length=1 ) return response[0] == 0x0 def ntag2xx_write_block(self, block_number: int, data: ReadableBuffer) -> bool: """Write a block of data to the card. Block number should be the block to write and data should be a byte array of length 4 with the data to write. If the data is successfully written then True is returned, otherwise False is returned. """ assert data is not None and len(data) == 4, "Data must be an array of 4 bytes!" # Build parameters for InDataExchange command to do NTAG203 classic write. params = bytearray(3 + len(data)) params[0] = 0x01 # Max card numbers params[1] = MIFARE_ULTRALIGHT_CMD_WRITE params[2] = block_number & 0xFF params[3:] = data # Send InDataExchange request. response = self.call_function( _COMMAND_INDATAEXCHANGE, params=params, response_length=1 ) return response[0] == 0x00 def ntag2xx_read_block( self, block_number: int ) -> Optional[Union[bytes, bytearray]]: """Read a block of data from the card. Block number should be the block to read. If the block is successfully read the first 4 bytes (after the leading 0x00 byte) will be returned. If the block is not read then None will be returned. """ ntag2xx_block = self.mifare_classic_read_block(block_number) if ntag2xx_block is not None: return ntag2xx_block[0:4] # only 4 bytes per page return None