Python LT8900 via SPI

class dummy_context_mgr():
	def __enter__(self):
		return None
	def __exit__(self, exc_type, exc_value, traceback):
		return False

class Radio:
	_default_register_values = {
		'format_config': {
			'crc_enabled': 1,
			'scramble_enabled': 0,
			'packet_length_encoded': 1,
			'auto_term_tx': 1,
			'auto_ack': 0,
			'pkt_fifo_polarity': 0,
			'crc_initial_data': 0
		},
		'radio_state': {'tx_enabled': 0, 'rx_enabled': 0, 'channel': 76},
		'power': {'current': 4, 'gain': 0},
		'rssi_power': {'mode': 0},
		'crystal': {'trim_adjust': 0},
		'packet_config': {
			'preamble_len': 2,
			'syncword_len': 1,
			'trailer_len': 0,
			'packet_type': 0,
			'fec_type': 0,
			'br_clock_sel': 0
		},
		'chip_power': {
			'power_down': 0,
			'sleep_mode': 0,
			'br_clock_on_sleep': 0,
			'rexmit_times': 3,
			'miso_tri_opt': 0,
			'scramble_value': 0
		},
		'thresholds': {
			'fifo_empty_threshold': 8,
			'fifo_full_threshold': 16,
			'syncword_error_bits': 2
		},
		'format_config': {
			'crc_enabled': 1,
			'scramble_enabled': 0,
			'packet_length_encoded': 1,
			'auto_term_tx': 1,
			'auto_ack': 0,
			'pkt_fifo_polarity': 0,
			'crc_initial_data': 0
		},
		'scan_rssi': {'channel': 63, 'ack_time': 176},
		'gain_block': {'enabled': 1},
		'vco_calibrate': {'enabled': 1},
		'scan_rssi_state': {'enabled': 0, 'channel_offset': 0, 'wait_time': 15}
	}
	_register_map = [
		{'name': "Unknown"}, # 0
		{'name': "Unknown"}, # 1
		{'name': "Unknown"}, # 2
		{                    # 3
			'name': 'phase_lock',
			'reserved_1': [13, 15],

		self._config['use_software_tx_queue'] = False
		self._spi.close()

	def _debug(self, message):
		if 'debug_log_command' in self._config:
			self._config['debug_log_command'](message)
		return None

	def _info(self, message):
		log_command = None
		if 'info_log_command' in self._config:
			log_command = self._config['info_log_command']
		elif 'debug_log_command' in self._config:
			log_command = self._config['debug_log_command']
		if log_command is None:
			return None

		log_command(message)
		return None

	def _error(self, message):
		log_command = None
		if 'error_log_command' in self._config:
			log_command = self._config['error_log_command']
		elif 'info_log_command' in self._config:
			log_command = self._config['info_log_command']
		elif 'debug_log_command' in self._config:
			log_command = self._config['debug_log_command']
		if log_command is None:
			return None
		log_command(message)
		return None

	def _get_mutex(self, real_mutex = True):
		if not real_mutex:
			return dummy_context_mgr()

		mutex = self._config.get('mutex', dummy_context_mgr())
		return mutex

	def _reset_device(self):
		self._info("Resetting radio {}".format(__name__))
		reset_command = self._config.get('reset_command', None)

		if reset_command is None:
			return None

		reset_command()

		value1 = self.get_register(0);
		value2 = self.get_register(1);

		if value1 == 0x6fe0 and value2 == 0x5681:
			return True
		return False

	def _get_default_register_value(self, register):


		return self._default_register_values.get(register, {})

	def _set_default_register_values(self):







		self._last_format_config = {}







		for register_name, register_value in self._default_register_values.items():




			if register_name == 'format_config':


				self._apply_packet_format_config({})



				continue


			self.put_register_bits(register_name, register_value)



		return True

	def _put_register_high_low(self, reg, high, low, delay = None):
		if delay is None:
			delay = 10

		reg = self._register_number(reg)

		result = self._spi.xfer([reg, high, low], self._spi.max_speed_hz, delay)

		if reg & 0x80 == 0x80:
			self._debug(" regRead[%02X] = %s" % ((reg & 0x7f), result))
		else:
			self._debug("regWrite[%02X:0x%02X%02X] = %s" % (reg, high, low, result))

		return result

	def put_register(self, reg, value, delay = None):
		high = (value >> 8) & 0xff
		low  = value & 0xff
		return self._put_register_high_low(reg, high, low, delay = delay)

	def put_register_bits(self, reg, bits_dict, delay = None):
		# Convert register to an integer
		reg = self._register_number(reg)

		# Lookup register in the register map
		register_info = self._register_map[reg]

		# Create a dictionary to hold the parsed results
		value = 0
		for key in bits_dict:
			if key == "name":
				continue
			bit_range = register_info[key]
			mask = ((1 << (bit_range[1] - bit_range[0] + 1)) - 1) << bit_range[0]
			key_value = (bits_dict[key] << bit_range[0]) & mask
			value = value | key_value

		result = self.put_register(reg, value, delay = delay)

		return result

	def get_register(self, reg):
		# Convert register to an integer
		reg = self._register_number(reg)

				self._software_tx_queue_mutex = None

		return None

	def initialize(self):
		self._reset_device()

		self._set_default_register_values()

		if not self._check_radio():
			return False
		return True

	def _reinitialize(self):
		self.initialize()
		self.set_syncword(self._last_syncword, submit_queue = None, force = True)
		self._apply_packet_format_config(self._last_format_config)

	def set_channel(self, channel):
		state = self.get_register_bits('radio_state')
		state['channel'] = channel

		self.put_register_bits('radio_state', state)

		return state

		return None

	def fill_fifo(self, message, include_length = True, lock = True):
		new_message = [self._register_number('fifo')]
		if include_length:
			new_message = new_message + [len(message)]
		new_message = new_message + message
		log_message = new_message.copy()

		delay = 10 * len(message)

		# Transfer the message
		with self._get_mutex(lock):
			result = self._spi.xfer(new_message, self._spi.max_speed_hz, delay)

		self._debug("Writing: {} = {}".format(log_message, result))

		need_reset = False
		for check_result in result:
			if check_result != 1:
				need_reset = True

		if need_reset:
			self._error("While transmitting we got an error, reinitializing everything")
			self._reinitialize()

		return new_message

	def transmit(self, message, channel = None, lock = True, post_delay = 0, syncword = None, submit_queue = '__DEFAULT__', format_config = None):
		# If we are using a radio transmit queue, just queue this message
		# (unless we are called from the dequeue procedure)
		if submit_queue is not None and self._should_use_queue():
			if syncword is None:
				syncword = self._last_syncword
			self._enqueue(submit_queue, syncword, message, channel, post_delay = post_delay, format_config = format_config)
			return True

		sent_packet = True

		with self._get_mutex(lock):
			# Set the syncword
			if syncword is not None:
				self.set_syncword(syncword, submit_queue = None)

			# Apply any format changes
			radio_format_config = self._apply_packet_format_config(format_config)

			# Determine if the length should be included
			if radio_format_config['packet_length_encoded'] == 1:
				include_length = True
			else:
				include_length = False

			if radio_format_config['auto_term_tx'] == 1:
				manual_terminate = False
			else:
				manual_terminate = True

			if channel is None:
				state = self.get_register_bits('radio_state')
				channel = state['channel']

			# Initialize the transmitter
			self.put_register_bits('radio_state', {
				'tx_enabled': 0,
				'rx_enabled': 0,
				'channel': 0
			})

			self.put_register_bits('fifo_state', {
				'clear_read': 1,
				'clear_write': 1
			})

			# Format message to send to fifo
			self.fill_fifo(message, include_length = include_length, lock = False)

			# Tell the radio to transmit the FIFO buffer to the specified channel
			self.put_register_bits('radio_state', {
				'tx_enabled': 1,
				'rx_enabled': 0,
				'channel': channel
			}, delay = 1000)



			while not manual_terminate:
				radio_status = self.get_register_bits('status')
				self._debug("radio_status={}".format(radio_status))

				if radio_status['packet_flag'] == 1:
					break

				if radio_status['framer_status'] == 0:
					sent_packet = False
					break
				time.sleep(0.001)

			# Stop transmitting, if needed
			if manual_terminate:
				self.put_register_bits('radio_state', {
					'tx_enabled': 0,
					'rx_enabled': 0,
					'channel': channel
				})

		if post_delay != 0:
			time.sleep(post_delay)

		return sent_packet

	def multi_transmit(self, message, channels, retries = 3, delay = 0.1, syncword = None, submit_queue = '__DEFAULT__', format_config = None):
		if len(channels) == 0 or retries == 0:
			self._error("Asked to send the message {} a total of zero times ({} channels, {} retries)".format(message, channels, retries))

		# Wait at-least 350 microseconds between frames
		min_delay = 350.0 / 1000000.0
		final_delay = max(min_delay, delay - (min_delay * (len(channels) * retries - 1)))

		for channel_idx in range(len(channels)):
			if channel_idx == (len(channels) - 1):
				retries -= 1
			channel = channels[channel_idx]
			for i in range(retries):
				if not self.transmit(message, channel, post_delay = min_delay, syncword = syncword, submit_queue = submit_queue):
					return False
		if not self.transmit(message, channel, post_delay = final_delay, syncword = syncword, submit_queue = submit_queue, format_config = format_config):
			return False

		return True

	def _enqueue(self, submit_queue, syncword, message, channel, post_delay = 0, format_config = None):
		if not self._should_use_queue():
			raise ValueError('internal error: _enqueue called with queueing disabled')

		with self._software_tx_queue_mutex:
			if submit_queue not in self._software_tx_queue:
				self._software_tx_queue[submit_queue] = collections.deque([])

			self._software_tx_queue[submit_queue].append({
				'syncword': syncword,
				'message': message,
				'channel': channel,
				'post_delay': post_delay,
				'format_config': format_config
			})

		return None

	def _run_queue(self):
		self._debug("Started run_queue process")

				pop_items = 0
				for item in self._software_tx_queue[submit_queue]:
					pop_items += 1

					# If the last item we're about to transmit requires a delay, make
					# a note of it in the queue time and don't pull anything else
					# from this queue
					item['submit_queue'] = submit_queue
					if item['post_delay'] != 0:
						break

				# Pop off the items to transmit in this run into a list
				if pop_items != 0:
					self._debug("Found {} items to transmit in the {} queue".format(pop_items, submit_queue))
				while pop_items != 0:

		self._debug("Getting ready to transmit {} items".format(len(to_transmit)))
		with self._get_mutex():
			for item in to_transmit:
				self._debug("Transmitting item {}".format(item))
				syncword = item['syncword']
				message = item['message']
				channel = item['channel']
				format_config = item['format_config']

				if syncword is not None:
					default_syncword = syncword
				else:
					syncword = default_syncword

				if message is None or channel is None:
					continue

				self.transmit(message, channel, lock = False, submit_queue = None, syncword = syncword, post_delay = 0, format_config = format_config)
				self._software_tx_queue_next_time[item['submit_queue']] = time.time() + item['post_delay']

		return [len(to_transmit), remaining_items]
		
	def start_listening(self, channel):
		# Initialize the receiver
		self.stop_listening()

		self.put_register_bits('fifo_state', {
			'clear_read': 1,
			'clear_write': 1
		})

		return True

	def _apply_packet_format_config(self, format_config):
		# Apply radio format configuration difference from baseline
		radio_format_config = self._get_default_register_value('format_config').copy()

		# If a configuration was supplied, update what we want to apply
		if format_config is not None:
			radio_format_config.update(format_config)

		if radio_format_config == self._last_format_config:
			return radio_format_config

		self._last_format_config = radio_format_config

		self.put_register_bits('format_config', radio_format_config, delay = 5000)
		new_config = self.get_register_bits('format_config')
		self._info("Updated format_config to be {}".format(new_config))

		return radio_format_config

	def receive(self, channel = None, wait = False, length = None, format_config = None, wait_time = 0.1):
		# If a length is supplied, assume that the packet is not length encoded
		# but allow the user to override that by supplying a format config
		if length is not None:
			if format_config is None:
				format_config = {}
			if 'packet_length_encoded' not in format_config:
				format_config = format_config.copy()
				format_config['packet_length_encoded'] = 0

		with self._get_mutex():
			# Apply the current configuration, if it is already applied
			# this will be a no-op
			self._apply_packet_format_config(format_config)

			if wait:
				if channel is None:
					state = self.get_register_bits('radio_state')
					channel = state['channel']

				self.start_listening(channel)

			message = []

			crc_error_count = 0
			while True:
				radio_status = self.get_register_bits('status')
				self._debug("radio_status={}".format(radio_status))

				if radio_status['crc_error'] == 1:
					crc_error_count += 1
					if crc_error_count > 30:
						self._reinitialize()
			
					self.start_listening(channel)
					continue

				crc_error_count = 0

				if radio_status['packet_flag'] == 0:
					if wait:
						time.sleep(wait_time)
						continue
					else:
						self._unlock_radio()
						return None






				# Data is available, read it from the FIFO register
				# The first result will include the length

				fifo_data = self.get_register('fifo')

				if length is not None:
					message_length = length
					message += [fifo_data >> 8]
					message_length -= 1
				else:
					message_length = fifo_data >> 8

				if message_length == 0:
					self.start_listening(channel)
					continue

				# Keep track of the total message length to truncate it
				final_message_length = message_length