#!/usr/bin/env python
# -*- coding: utf-8 -*-
# The following specifications have been used
# as a basis for writing this example.
#
# NFC Data Exchange Format (NDEF), NDEF 1.0:
# https://github.com/Tinkerforge/nfc-rfid-bricklet/raw/master/datasheets/specification_ndef.pdf
#
# Type 1 Tag Operation Specification, T1TOP 1.1:
# https://github.com/Tinkerforge/nfc-rfid-bricklet/raw/master/datasheets/specification_type1.pdf
#
# Type 2 Tag Operation Specification, T2TOP 1.1:
# https://github.com/Tinkerforge/nfc-rfid-bricklet/raw/master/datasheets/specification_type2.pdf
from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_nfc_rfid import NFCRFID
try:
from Queue import Queue
except ImportError:
from queue import Queue
from pprint import pprint
import os
class NdefMessage:
tag_type = None
records = []
capability_container = [0, 0, 0, 0]
def __init__(self, tag_type):
self.tag_type = tag_type
def add_record(self, record):
self.records.append(record)
# Set end and begin flags as needed
if len(self.records) == 1:
record.begin = True
record.end = True
else:
self.records[-2].end = False
self.records[-1].end = True
def set_capability_container(self, version, tag_size, read_write_access):
# Magic number to indicate NFC Forum defined data is stored
self.capability_container[0] = 0xE1
self.capability_container[1] = version
if self.tag_type == NFCRFID.TAG_TYPE_TYPE1:
self.capability_container[2] = tag_size/8 - 1
else:
self.capability_container[2] = tag_size/8
self.capability_container[3] = read_write_access
def get_raw_data_in_chunks(self):
raw_data = []
for record in self.records:
raw_data.extend(record.get_raw_data())
# Use Three consecutive byte format if necessary, see 2.3 TLV blocks
data_len = len(raw_data)
if data_len < 0xFF:
tlv_ndef = [0x03, data_len]
else:
tlv_ndef = [0x03, 0xFF, data_len >> 8, data_len % 256]
if self.tag_type == NFCRFID.TAG_TYPE_TYPE1:
# CC set by set_capability_container
# default lock and memory TLVs
# NDEF TLV
# NDEF message
# Terminator TLV
raw_data = self.capability_container + \
[0x01, 0x03, 0xF2, 0x30, 0x33, 0x02, 0x03, 0xF0, 0x02, 0x03] + \
tlv_ndef + \
raw_data + \
[0xFE]
elif self.tag_type == NFCRFID.TAG_TYPE_TYPE2:
# CC set by set_capability_container
# NDEF TLV
# NDEF message
# Terminator TLV
raw_data = self.capability_container + \
tlv_ndef + \
raw_data + \
[0xFE]
else:
# TODO: We could support TAG_TYPE_MIFARE_CLASSIC here, but mifare classic
# it is not supported in modern smart phones anyway.
return [[]]
chunks = []
for i in range(0, len(raw_data), 16):
chunks.append(raw_data[i:i+16])
last_chunk_length = len(chunks[-1])
if last_chunk_length < 16:
chunks[-1].extend([0]*(16-last_chunk_length))
return chunks
class NdefRecord:
FLAG_ID_LENGTH = 1 << 3
FLAG_SHORT_RECORD = 1 << 4
FLAG_CHUNK = 1 << 5
FLAG_MESSAGE_END = 1 << 6
FLAG_MESSAGE_BEGIN = 1 << 7
TNF_EMPTY = 0x0
TNF_WELL_KNOWN = 0x01
TNF_MIME_MEDIA = 0x02
TNF_ABSOLUTE_URI = 0x03
TNF_EXTERNAL_TYPE = 0x04
TNF_UNKNOWN = 0x05
TNF_UNCHANGED = 0x06
TNF_RESERVED = 0x07
NDEF_URIPREFIX_NONE = 0x00
NDEF_URIPREFIX_HTTP_WWWDOT = 0x01
NDEF_URIPREFIX_HTTPS_WWWDOT = 0x02
NDEF_URIPREFIX_HTTP = 0x03
NDEF_URIPREFIX_HTTPS = 0x04
NDEF_URIPREFIX_TEL = 0x05
NDEF_URIPREFIX_MAILTO = 0x06
NDEF_URIPREFIX_FTP_ANONAT = 0x07
NDEF_URIPREFIX_FTP_FTPDOT = 0x08
NDEF_URIPREFIX_FTPS = 0x09
NDEF_URIPREFIX_SFTP = 0x0A
NDEF_URIPREFIX_SMB = 0x0B
NDEF_URIPREFIX_NFS = 0x0C
NDEF_URIPREFIX_FTP = 0x0D
NDEF_URIPREFIX_DAV = 0x0E
NDEF_URIPREFIX_NEWS = 0x0F
NDEF_URIPREFIX_TELNET = 0x10
NDEF_URIPREFIX_IMAP = 0x11
NDEF_URIPREFIX_RTSP = 0x12
NDEF_URIPREFIX_URN = 0x13
NDEF_URIPREFIX_POP = 0x14
NDEF_URIPREFIX_SIP = 0x15
NDEF_URIPREFIX_SIPS = 0x16
NDEF_URIPREFIX_TFTP = 0x17
NDEF_URIPREFIX_BTSPP = 0x18
NDEF_URIPREFIX_BTL2CAP = 0x19
NDEF_URIPREFIX_BTGOEP = 0x1A
NDEF_URIPREFIX_TCPOBEX = 0x1B
NDEF_URIPREFIX_IRDAOBEX = 0x1C
NDEF_URIPREFIX_FILE = 0x1D
NDEF_URIPREFIX_URN_EPC_ID = 0x1E
NDEF_URIPREFIX_URN_EPC_TAG = 0x1F
NDEF_URIPREFIX_URN_EPC_PAT = 0x20
NDEF_URIPREFIX_URN_EPC_RAW = 0x21
NDEF_URIPREFIX_URN_EPC = 0x22
NDEF_URIPREFIX_URN_NFC = 0x23
NDEF_TYPE_MIME = 0x02
NDEF_TYPE_URI = 0x55
NDEF_TYPE_TEXT = 0x54
begin = False
end = False
tnf = 0
record_type = None
payload = None
identifier = None
def set_identifier(self, identifier):
self.identifier = identifier
def get_raw_data(self):
if self.record_type == None or self.payload == None:
return []
# Construct tnf and flags (byte 0 of header)
header = [self.tnf]
if self.begin:
header[0] |= NdefRecord.FLAG_MESSAGE_BEGIN
if self.end:
header[0] |= NdefRecord.FLAG_MESSAGE_END
if len(self.payload) < 256:
header[0] |= NdefRecord.FLAG_SHORT_RECORD
if self.identifier != None:
header[0] |= NdefRecord.FLAG_ID_LENGTH
# Type length (byte 1 of header)
header.append(len(self.record_type))
# Payload length (byte 2 of header)
# TODO: payload > 255?
header.append(len(self.payload))
# ID length (byte 3 of header)
if self.identifier != None:
header.append(len(self.identifier))
# Record type (byte 4ff of header)
header.extend(self.record_type)
# ID
if self.identifier != None:
header.extend(self.identifier)
return header + self.payload
class NdefTextRecord(NdefRecord):
# Call with text and ISO/IANA language code
def __init__(self, text, language='en'):
self.tnf = NdefRecord.TNF_WELL_KNOWN
self.record_type = [NdefRecord.NDEF_TYPE_TEXT]
lang_list = map(ord, language)
text_list = map(ord, text)
# Text Record Content: Status byte, ISO/IANA language code, text
# See NDEF 1.0: 3.2.1
self.payload = [len(lang_list)] + lang_list + text_list
class NdefUriRecord(NdefRecord):
def __init__(self, uri, uri_prefix=NdefRecord.NDEF_URIPREFIX_NONE):
self.tnf = NdefRecord.TNF_WELL_KNOWN
self.record_type = [NdefRecord.NDEF_TYPE_URI]
uri_list = map(ord, uri)
# Text Record Content: URI prefix, URI
# See NDEF 1.0: 3.2.2
self.payload = [uri_prefix] + uri_list
class NdefMediaRecord(NdefRecord):
def __init__(self, mime_type, data):
self.tnf = NdefRecord.TNF_MIME_MEDIA
self.record_type = map(ord, mime_type)
if type(data) == str:
self.payload = map(ord, data)
else:
self.payload = data
class ExampleNdef:
HOST = "localhost"
PORT = 4223
UID = "hjw" # Change to your UID
state_queue = Queue()
tag_type = None
tag_size = None
def __init__(self, tag_type, tag_size=512):
self.tag_type = tag_type
self.tag_size = tag_size
self.ipcon = IPConnection() # Create IP connection
self.nfc = NFCRFID(self.UID, self.ipcon) # Create device object
self.ipcon.connect(self.HOST, self.PORT) # Connect to brickd
self.nr.register_callback(self.nr.CALLBACK_STATE_CHANGED, self.state_changed)
def write_message(self):
chunks = self.message.get_raw_data_in_chunks()
print("Trying to write the follwing data to the tag:")
pprint(chunks)
self.nr.request_tag_id(self.tag_type)
state = self.state_queue.get()
if state != self.nr.STATE_REQUEST_TAG_ID:
return -1
state = self.state_queue.get()
if state != self.nr.STATE_REQUEST_TAG_ID_READY:
return -2
# NFC Forum Type 1 start page is 1 (start of capability container)
# NFC Forum Type 2 start page is 3 (start of capability container)
if self.tag_type == NFCRFID.TAG_TYPE_TYPE1:
current_page = 1
else:
current_page = 3
for chunk in chunks:
self.nr.write_page(current_page, chunk)
state = self.state_queue.get()
if state != self.nr.STATE_WRITE_PAGE:
return -3
state = self.state_queue.get()
if state != self.nr.STATE_WRITE_PAGE_READY:
return -4
# NFC Forum Type 1 has 2 pages per chunk (16 byte)
# NFC Forum Type 2 has 4 pages per chunk (16 byte)
if self.tag_type == NFCRFID.TAG_TYPE_TYPE1 :
current_page += 2
else:
current_page += 4
return 0
def state_changed(self, state, idle):
self.state_queue.put(state)
def make_message_small(self):
self.message = NdefMessage(self.tag_type)
# Capabilities:
# Version 1.0 (0x10)
# Tag size bytes (given by self.tag_size)
# Read/write access for all (0x00)
self.message.set_capability_container(0x10, self.tag_size, 0x00)
record = NdefUriRecord('tinkerforge.com', NdefRecord.NDEF_URIPREFIX_HTTP_WWWDOT)
self.message.add_record(record)
def make_message_large(self):
self.message = NdefMessage(self.tag_type)
# Capabilities:
# Version 1.0 (0x10)
# Tag size bytes (given by self.tag_size)
# Read/write access for all (0x00)
self.message.set_capability_container(0x10, self.tag_size, 0x00)
rec1 = NdefTextRecord('Hello World', 'en')
self.message.add_record(rec1)
rec2 = NdefTextRecord('Hallo Welt', 'de')
self.message.add_record(rec2)
rec3 = NdefUriRecord('tinkerforge.com', NdefRecord.NDEF_URIPREFIX_HTTP_WWWDOT)
self.message.add_record(rec3)
text = '<html><head><title>Hello</title></head><body>World!</body></html>'
rec4 = NdefMediaRecord('text/html', text)
self.message.add_record(rec4)
# To test an "image/png" you can can download the file from:
# http://download.tinkerforge.com/_stuff/tf_16x16.png
if os.path.isfile('tf_16x16.png'):
logo = file('tf_16x16.png').read()
rec5 = NdefMediaRecord('image/png', map(ord, logo))
self.message.add_record(rec5)
if __name__ == '__main__':
example = ExampleNdef(tag_type=NFCRFID.TAG_TYPE_TYPE2, tag_size=888)
# example.make_message_large() # Writes different texts, URI, html site and image
example.make_message_small() # Writes simple URI record
ret = example.write_message()
if ret < 0:
print('Could not write NDEF Message: ' + str(ret))
else:
print('NDEF Message written successfully')
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