ir_rx/acquire.py

   1 # acquire.py Acquire a pulse train from an IR remote
   2 # Supports NEC protocol.
   3 # For a remote using NEC see https://www.adafruit.com/products/389
   4
   5 # Author: Peter Hinch
   6 # Copyright Peter Hinch 2020 Released under the MIT license
   7
   8 from machine import Pin, freq
   9 from sys import platform
  10
  11 from utime import sleep_ms, ticks_us, ticks_diff
  12 from ir_rx import IR_RX
  13
  14
  15 class IR_GET(IR_RX):
  16     def __init__(self, pin, nedges=100, twait=100, display=True):
  17         self.display = display
  18         super().__init__(pin, nedges, twait, lambda *_ : None)
  19         self.data = None
  20
  21     def decode(self, _):
  22         def near(v, target):
  23             return target * 0.8 < v < target * 1.2
  24         lb = self.edge - 1  # Possible length of burst
  25         if lb < 3:
  26             return  # Noise
  27         burst = []
  28         for x in range(lb):
  29             dt = ticks_diff(self._times[x + 1], self._times[x])
  30             if x > 0 and dt > 10000:  # Reached gap between repeats
  31                 break
  32             burst.append(dt)
  33         lb = len(burst)  # Actual length
  34         # Duration of pulse train 24892 for RC-5 22205 for RC-6
  35         duration = ticks_diff(self._times[lb - 1], self._times[0])
  36
  37         if self.display:
  38             for x, e in enumerate(burst):
  39                 print('{:03d} {:5d}'.format(x, e))
  40             print()
  41             # Attempt to determine protocol
  42             ok = False  # Protocol not yet found
  43             if near(burst[0], 9000) and lb == 67:
  44                 print('NEC')
  45                 ok = True
  46
  47             if not ok and near(burst[0], 2400) and near(burst[1], 600):  # Maybe Sony
  48                 try:
  49                     nbits = {25:12, 31:15, 41:20}[lb]
  50                 except KeyError:
  51                     pass
  52                 else:
  53                     ok = True
  54                     print('Sony {}bit'.format(nbits))
  55
  56             if not ok and near(burst[0], 889):  # Maybe RC-5
  57                 if near(duration, 24892) and near(max(burst), 1778):
  58                     print('Philps RC-5')
  59                     ok = True
  60
  61             if not ok and near(burst[0], 2666) and near(burst[1], 889):  # RC-6?
  62                 if near(duration, 22205) and near(burst[1], 889) and near(burst[2], 444):
  63                     print('Philips RC-6 mode 0')
  64                     ok = True
  65
  66             if not ok and near(burst[0], 2000) and near(burst[1], 1000):
  67                 if near(duration, 19000):
  68                     print('Microsoft MCE edition protocol.')
  69                     # Constant duration, variable burst length, presumably bi-phase
  70                     print('Protocol start {} {} Burst length {} duration {}'.format(burst[0], burst[1], lb, duration))
  71                     ok = True
  72
  73             if not ok and near(burst[0], 4500) and near(burst[1], 4500):  # Samsung?
  74                 print('Unsupported protocol. Samsung?')
  75                 ok = True
  76
  77             if not ok and near(burst[0], 3500) and near(burst[1], 1680):  # Panasonic?
  78                 print('Unsupported protocol. Panasonic?')
  79                 ok = True
  80
  81             if not ok:
  82                 print('Unknown protocol start {} {} Burst length {} duration {}'.format(burst[0], burst[1], lb, duration))
  83
  84             print()
  85         self.data = burst
  86         # Set up for new data burst. Run null callback
  87         self.do_callback(0, 0, 0)
  88
  89     def acquire(self):
  90         while self.data is None:
  91             sleep_ms(5)
  92         self.close()
  93         return self.data
  94
  95 def test():
  96     # Define pin according to platform
  97     if platform == 'pyboard':
  98         pin = Pin('X3', Pin.IN)
  99     elif platform == 'esp8266':
 100         freq(160000000)
 101         pin = Pin(13, Pin.IN)
 102     elif platform == 'esp32' or platform == 'esp32_LoBo':
 103         pin = Pin(23, Pin.IN)
 104     irg = IR_GET(pin)
 105     print('Waiting for IR data...')
 106     return irg.acquire()