lint & add example

Author: ladyada

adafruit_pn532.py

@@ -456,7 +456,7 @@ def ntag2xx_write_block(self, block_number, data):
                                       params=params,
                                       response_length=1)
         return response[0] == 0x00
-    
+
     def ntag2xx_read_block(self, block_number):
         """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

examples/readwrite_ntag2xx.py

@@ -0,0 +1,81 @@
+# Example of detecting and reading a block from a MiFare NFC card.
+# Author: Tony DiCola & Roberto Laricchia
+# Copyright (c) 2015 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.
+
+"""
+This example shows connecting to the PN532 and writing & reading an ntag2xx
+type RFID tag
+"""
+
+import board
+import busio
+from digitalio import DigitalInOut
+from Adafruit_Circuitpython_PN532 import adafruit_pn532
+
+# I2C connection:
+#i2c = busio.I2C(board.SCL, board.SDA)
+
+# Non-hardware reset/request with I2C
+#pn532 = adafruit_pn532.PN532_I2C(i2c, debug=False)
+
+# With I2C, we recommend connecting RSTPD_N (reset) to a digital pin for manual
+# harware reset
+#reset_pin = DigitalInOut(board.D6)
+# On Raspberry Pi, you must also connect a pin to P32 "H_Request" for hardware
+# wakeup! this means we don't need to do the I2C clock-stretch thing
+#req_pin = DigitalInOut(board.D12)
+#pn532 = adafruit_pn532.PN532_I2C(i2c, debug=False, reset=reset_pin, req=req_pin)
+
+# SPI connection:
+spi = busio.SPI(board.SCK, board.MOSI, board.MISO)
+cs_pin = DigitalInOut(board.D5)
+pn532 = adafruit_pn532.PN532_SPI(spi, cs_pin, debug=False)
+
+# UART connection
+#uart = busio.UART(board.TX, board.RX, baudrate=115200, timeout=100)
+#pn532 = adafruit_pn532.PN532_UART(uart, debug=False)
+
+ic, ver, rev, support = pn532.get_firmware_version()
+print('Found PN532 with firmware version: {0}.{1}'.format(ver, rev))
+
+# Configure PN532 to communicate with MiFare cards
+pn532.SAM_configuration()
+
+print('Waiting for RFID/NFC card to write to!')
+while True:
+    # Check if a card is available to read
+    uid = pn532.read_passive_target(timeout=0.5)
+    print('.', end="", flush=True)
+    # Try again if no card is available.
+    if uid is not None:
+        break
+
+print("")
+print('Found card with UID:', [hex(i) for i in uid])
+
+# Set 4 bytes of block to 0xFEEDBEEF
+data = bytearray(4)
+data[0:4] = [0xFE, 0xED, 0xBE, 0xEF]
+# Write 4 byte block.
+pn532.ntag2xx_write_block(6, data)
+# Read block #6
+print('Wrote to block 6, now trying to read that data:',
+      [hex(x) for x in pn532.ntag2xx_read_block(6)])