Files
Home-AssistantConfig/deps/rpi_rf/rpi_rf.py
2016-10-11 16:42:06 +00:00

232 lines
8.0 KiB
Python

"""
Sending and receiving 433Mhz signals with cheap GPIO RF Modules on a Raspberry Pi.
"""
import logging
import time
from collections import namedtuple
from RPi import GPIO
MAX_CHANGES = 67
_LOGGER = logging.getLogger(__name__)
Protocol = namedtuple('Protocol',
['pulselength',
'sync_high', 'sync_low',
'zero_high', 'zero_low',
'one_high', 'one_low'])
PROTOCOLS = (None,
Protocol(350, 1, 31, 1, 3, 3, 1),
Protocol(650, 1, 10, 1, 2, 2, 1),
Protocol(100, 30, 71, 4, 11, 9, 6),
Protocol(380, 1, 6, 1, 3, 3, 1),
Protocol(500, 6, 14, 1, 2, 2, 1))
class RFDevice:
"""Representation of a GPIO RF device."""
# pylint: disable=too-many-instance-attributes,too-many-arguments
def __init__(self, gpio,
tx_proto=1, tx_pulselength=None, tx_repeat=10, tx_length=24, rx_tolerance=80):
"""Initialize the RF device."""
self.gpio = gpio
self.tx_enabled = False
self.tx_proto = tx_proto
if tx_pulselength:
self.tx_pulselength = tx_pulselength
else:
self.tx_pulselength = PROTOCOLS[tx_proto].pulselength
self.tx_repeat = tx_repeat
self.tx_length = tx_length
self.rx_enabled = False
self.rx_tolerance = rx_tolerance
# internal values
self._rx_timings = [0] * (MAX_CHANGES + 1)
self._rx_last_timestamp = 0
self._rx_change_count = 0
self._rx_repeat_count = 0
# successful RX values
self.rx_code = None
self.rx_code_timestamp = None
self.rx_proto = None
self.rx_bitlength = None
self.rx_pulselength = None
GPIO.setmode(GPIO.BCM)
_LOGGER.debug("Using GPIO " + str(gpio))
def cleanup(self):
"""Disable TX and RX and clean up GPIO."""
if self.tx_enabled:
self.disable_tx()
if self.rx_enabled:
self.disable_rx()
_LOGGER.debug("Cleanup")
GPIO.cleanup()
def enable_tx(self):
"""Enable TX, set up GPIO."""
if self.rx_enabled:
_LOGGER.error("RX is enabled, not enabling TX")
return False
if not self.tx_enabled:
self.tx_enabled = True
GPIO.setup(self.gpio, GPIO.OUT)
_LOGGER.debug("TX enabled")
return True
def disable_tx(self):
"""Disable TX, reset GPIO."""
if self.tx_enabled:
# set up GPIO pin as input for safety
GPIO.setup(self.gpio, GPIO.IN)
self.tx_enabled = False
_LOGGER.debug("TX disabled")
return True
def tx_code(self, code, tx_proto=None, tx_pulselength=None):
"""
Send a decimal code.
Optionally set protocol and pulselength.
When none given reset to default protocol and pulselength.
"""
if tx_proto:
self.tx_proto = tx_proto
else:
self.tx_proto = 1
if tx_pulselength:
self.tx_pulselength = tx_pulselength
else:
self.tx_pulselength = PROTOCOLS[self.tx_proto].pulselength
rawcode = format(code, '#0{}b'.format(self.tx_length + 2))[2:]
_LOGGER.debug("TX code: " + str(code))
return self.tx_bin(rawcode)
def tx_bin(self, rawcode):
"""Send a binary code."""
_LOGGER.debug("TX bin: " + str(rawcode))
for _ in range(0, self.tx_repeat):
for byte in range(0, self.tx_length):
if rawcode[byte] == '0':
if not self.tx_l0():
return False
else:
if not self.tx_l1():
return False
if not self.tx_sync():
return False
return True
def tx_l0(self):
"""Send a '0' bit."""
if not 0 < self.tx_proto < len(PROTOCOLS):
_LOGGER.error("Unknown TX protocol")
return False
return self.tx_waveform(PROTOCOLS[self.tx_proto].zero_high,
PROTOCOLS[self.tx_proto].zero_low)
def tx_l1(self):
"""Send a '1' bit."""
if not 0 < self.tx_proto < len(PROTOCOLS):
_LOGGER.error("Unknown TX protocol")
return False
return self.tx_waveform(PROTOCOLS[self.tx_proto].one_high,
PROTOCOLS[self.tx_proto].one_low)
def tx_sync(self):
"""Send a sync."""
if not 0 < self.tx_proto < len(PROTOCOLS):
_LOGGER.error("Unknown TX protocol")
return False
return self.tx_waveform(PROTOCOLS[self.tx_proto].sync_high,
PROTOCOLS[self.tx_proto].sync_low)
def tx_waveform(self, highpulses, lowpulses):
"""Send basic waveform."""
if not self.tx_enabled:
_LOGGER.error("TX is not enabled, not sending data")
return False
GPIO.output(self.gpio, GPIO.HIGH)
time.sleep((highpulses * self.tx_pulselength) / 1000000)
GPIO.output(self.gpio, GPIO.LOW)
time.sleep((lowpulses * self.tx_pulselength) / 1000000)
return True
def enable_rx(self):
"""Enable RX, set up GPIO and add event detection."""
if self.tx_enabled:
_LOGGER.error("TX is enabled, not enabling RX")
return False
if not self.rx_enabled:
self.rx_enabled = True
GPIO.setup(self.gpio, GPIO.IN)
GPIO.add_event_detect(self.gpio, GPIO.BOTH)
GPIO.add_event_callback(self.gpio, self.rx_callback)
_LOGGER.debug("RX enabled")
return True
def disable_rx(self):
"""Disable RX, remove GPIO event detection."""
if self.rx_enabled:
GPIO.remove_event_detect(self.gpio)
self.rx_enabled = False
_LOGGER.debug("RX disabled")
return True
# pylint: disable=unused-argument
def rx_callback(self, gpio):
"""RX callback for GPIO event detection. Handle basic signal detection."""
timestamp = int(time.perf_counter() * 1000000)
duration = timestamp - self._rx_last_timestamp
if duration > 5000:
if duration - self._rx_timings[0] < 200:
self._rx_repeat_count += 1
self._rx_change_count -= 1
if self._rx_repeat_count == 2:
for pnum in range(1, len(PROTOCOLS)):
if self._rx_waveform(pnum, self._rx_change_count, timestamp):
_LOGGER.debug("RX code " + str(self.rx_code))
break
self._rx_repeat_count = 0
self._rx_change_count = 0
if self._rx_change_count >= MAX_CHANGES:
self._rx_change_count = 0
self._rx_repeat_count = 0
self._rx_timings[self._rx_change_count] = duration
self._rx_change_count += 1
self._rx_last_timestamp = timestamp
def _rx_waveform(self, pnum, change_count, timestamp):
"""Detect waveform and format code."""
code = 0
delay = int(self._rx_timings[0] / PROTOCOLS[pnum].sync_low)
delay_tolerance = delay * self.rx_tolerance / 100
for i in range(1, change_count, 2):
if (self._rx_timings[i] - delay * PROTOCOLS[pnum].zero_high < delay_tolerance and
self._rx_timings[i+1] - delay * PROTOCOLS[pnum].zero_low < delay_tolerance):
code <<= 1
elif (self._rx_timings[i] - delay * PROTOCOLS[pnum].one_high < delay_tolerance and
self._rx_timings[i+1] - delay * PROTOCOLS[pnum].one_low < delay_tolerance):
code <<= 1
code |= 1
else:
return False
if self._rx_change_count > 6 and code != 0:
self.rx_code = code
self.rx_code_timestamp = timestamp
self.rx_bitlength = int(change_count / 2)
self.rx_pulselength = delay
self.rx_proto = pnum
return True
return False