# Adafruit PN532 NFC/RFID control library. # Author: Tony DiCola # # The MIT License (MIT) # # Copyright (c) 2015-2018 Adafruit Industries # # Permission is hereby granted, free of charge, to any person obtaining a copy # of this software and associated documentation files (the "Software"), to deal # in the Software without restriction, including without limitation the rights # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell # copies of the Software, and to permit persons to whom the Software is # furnished to do so, subject to the following conditions: # # The above copyright notice and this permission notice shall be included in # all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN # THE SOFTWARE. """ ``adafruit_pn532.uart`` ==================================================== This module will let you communicate with a PN532 RFID/NFC shield or breakout using UART. * Author(s): Original Raspberry Pi code by Tony DiCola, CircuitPython by ladyada, refactor by Carter Nelson """ __version__ = "0.0.0-auto.0" __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_PN532.git" import time from adafruit_pn532.adafruit_pn532 import PN532, BusyError class PN532_UART(PN532): """Driver for the PN532 connected over Serial UART""" def __init__(self, uart, *, reset=None, debug=False): """Create an instance of the PN532 class using Serial connection. Optional reset pin and debugging output. """ self.debug = debug self._uart = uart super().__init__(debug=debug, reset=reset) def _wakeup(self): """Send any special commands/data to wake up PN532""" if self._reset_pin: self._reset_pin.value = True time.sleep(0.01) self.low_power = False self._uart.write( b"\x55\x55\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" ) # wake up! self.SAM_configuration() def _wait_ready(self, timeout=1): """Wait `timeout` seconds""" timestamp = time.monotonic() while (time.monotonic() - timestamp) < timeout: if self._uart.in_waiting > 0: return True # No Longer Busy time.sleep(0.01) # lets ask again soon! # Timed out! return False def _read_data(self, count): """Read a specified count of bytes from the PN532.""" frame = self._uart.read(count) if not frame: raise BusyError("No data read from PN532") if self.debug: print("Reading: ", [hex(i) for i in frame]) return frame def _write_data(self, framebytes): """Write a specified count of bytes to the PN532""" self._uart.reset_input_buffer() self._uart.write(framebytes)