from micropython import const
from array import array
-import micropython
-
+from time import ticks_us, ticks_diff
+# import micropython
# micropython.alloc_emergency_exception_buf(100)
-# Duty ratio in carrier off state.
-_SPACE = const(0)
# On ESP32 gate hardware design is led_on = rmt and carrier
# Shared by NEC
# IR abstract base class. Array holds periods in μs between toggling 36/38KHz
# carrier on or off. Physical transmission occurs in an ISR context controlled
-# by timer 2 and timer 5. See README.md for details of operation.
+# by timer 2 and timer 5. See TRANSMITTER.md for details of operation.
class IR:
- active_high = True # Hardware turns IRLED on if pin goes high.
+ _active_high = True # Hardware turns IRLED on if pin goes high.
+ _space = 0 # Duty ratio that causes IRLED to be off
+ timeit = False # Print timing info
+
+ @classmethod
+ def active_low(cls):
+ if ESP32:
+ raise ValueError('Cannot set active low on ESP32')
+ cls._active_high = False
+ cls._space = 100
def __init__(self, pin, cfreq, asize, duty, verbose):
- if not IR.active_high:
- duty = 100 - duty
if ESP32:
self._pwm = PWM(pin[0]) # Continuous 36/38/40KHz carrier
self._pwm.deinit()
self._pwm.init(freq=cfreq, duty=round(duty * 10.23))
self._rmt = RMT(0, pin=pin[1], clock_div=80) # 1μs resolution
else: # Pyboard
+ if not IR._active_high:
+ duty = 100 - duty
tim = Timer(2, freq=cfreq) # Timer 2/pin produces 36/38/40KHz carrier
self._ch = tim.channel(1, Timer.PWM, pin=pin)
- self._ch.pulse_width_percent(_SPACE) # Turn off IR LED
+ self._ch.pulse_width_percent(self._space) # Turn off IR LED
# Pyboard: 0 <= pulse_width_percent <= 100
self._duty = duty
self._tim = Timer(5) # Timer 5 controls carrier on/off times
p = self.aptr
v = self._arr[p]
if v == STOP:
- self._ch.pulse_width_percent(_SPACE) # Turn off IR LED.
+ self._ch.pulse_width_percent(self._space) # Turn off IR LED.
return
- self._ch.pulse_width_percent(_SPACE if p & 1 else self._duty)
+ self._ch.pulse_width_percent(self._space if p & 1 else self._duty)
self._tim.init(prescaler=84, period=v, callback=self._tcb)
self.aptr += 1
# Public interface
# Before populating array, zero pointer, set notional carrier state (off).
- def transmit(self, addr, data, toggle=0): # NEC: toggle is unused
+ def transmit(self, addr, data, toggle=0, validate=False): # NEC: toggle is unused
+ t = ticks_us()
+ if validate:
+ if addr > self.valid[0] or addr < 0:
+ raise ValueError('Address out of range', addr)
+ if data > self.valid[1] or data < 0:
+ raise ValueError('Data out of range', data)
+ if toggle > self.valid[2] or toggle < 0:
+ raise ValueError('Toggle out of range', toggle)
self.aptr = 0 # Inital conditions for tx: index into array
self.carrier = False
self.tx(addr, data, toggle) # Subclass populates ._arr
self.trigger() # Initiate transmission
+ if self.timeit:
+ dt = ticks_diff(ticks_us(), t)
+ print('Time = {}μs'.format(dt))
# Subclass interface
def trigger(self): # Used by NEC to initiate a repeat frame
self.verbose and print('add', t)
# .carrier unaffected
self._arr[self.aptr - 1] += t
+
+
+# Given an iterable (e.g. list or tuple) of times, emit it as an IR stream.
+class Player(IR):
+
+ def __init__(self, pin, freq=38000, verbose=False): # NEC specifies 38KHz
+ super().__init__(pin, freq, 68, 33, verbose) # Measured duty ratio 33%
+
+ def play(self, lst):
+ for x, t in enumerate(lst):
+ self._arr[x] = t
+ self.aptr = x + 1
+ self.trigger()