Example #1
0
def tone(pin, frequency, duration=None):
  """Generates a square wave of the specified frequency on pin.

  Args:

  - pin(PWM1 to PWM6): A PWM pin
  - frequency(int): A value between 1 and 500000
  - duration(int): tone's durations in second

  """
  global pwm_pins

  if pin not in pwm_pins:
    print "Pin must be one of:"
    for key in pwm_pins:
      print key
    exit(1)

  if frequency < 1 or frequency > 500000:
    print "Invalid frequency"
    exit(1)

  initMatch(0, 1000000/frequency)
  initMatch(pwm_pins[pin], 500000/frequency)

  PWM_ChannelCmd(LPC_PWM1, pwm_pins[pin], FunctionalState.ENABLE)
  PWM_ResetCounter(LPC_PWM1)
  PWM_CounterCmd(LPC_PWM1, FunctionalState.ENABLE)
  PWM_Cmd(LPC_PWM1, FunctionalState.ENABLE)

  if duration:
    t = threading.Timer(float(duration)/1000.0, noTone, [pin])
    t.start()
Example #2
0
def analogWrite(pin, value):
  """Writes an analog value (PWM wave) to a pin.

  Args:

  - pin(PWM1 to PWM6): A PWM pin
  - value(int): Duty cycle, a value between 0 and 255

  """
  global pwm_pins

  if pin not in pwm_pins:
    print "Pin must be one of:"
    for key in pwm_pins:
      print key
    exit(1)

  if value < 0 or value > 255:
    print "Invalid duty cycle"
    exit(1)

  # 490Hz
  period = 1000000/490
  pulse_width = period*value/255
  initMatch(0, period)
  initMatch(pwm_pins[pin], pulse_width)

  PWM_ChannelCmd(LPC_PWM1, pwm_pins[pin], FunctionalState.ENABLE)
  PWM_ResetCounter(LPC_PWM1)
  PWM_CounterCmd(LPC_PWM1, FunctionalState.ENABLE)
  PWM_Cmd(LPC_PWM1, FunctionalState.ENABLE)
Example #3
0
    def add_channel(self, raw_channel, init_pulse):
        """Add PWM channel with a 1.5ms pulse.
        """
        try:
            channel = int(raw_channel)
            if channel < 1 or channel > 5:
                raise InputError
        except:
            self.log.warning("%s is an invalid channel." % raw_channel)
            return None 
        
        # Check if channel has already been added
        if channel in self.channels:
            self.log.warning("Channel %d has already been initialized." % channel)
            return None

        self.channels.append(channel)

        initMatch(channel, init_pulse)
        PWM_ChannelCmd(LPC_PWM1, channel, FunctionalState.ENABLE)
        #TODO: might need counter commands here. check this first.

        self.log.info("Initializing BLDC pwm channel %d." % channel)
Example #4
0
    def __init__(self, config):

        log = config.get('log_facility')

        period = config.getint('bldc', 'pwm_period')
        log.info("Set pwm period to %d" % period)
        initMatch(0, period)

        PWM_ResetCounter(LPC_PWM1)
        PWM_CounterCmd(LPC_PWM1, FunctionalState.ENABLE)
        PWM_Cmd(LPC_PWM1, FunctionalState.ENABLE)

        self.log = log
        self.config = config
        self.channels = []

        channels = config.getlist('bldc', 'channels')
        init_pulse = config.getint('bldc', 'init_pulse')
        log.info("Attempting to add channel(s) %s at pulse %d" % (channels, init_pulse))
        for channel in channels:
            self.add_channel(channel, init_pulse)

        log.info("Initialized BLDC motor controller.")  
Example #5
0
def initPeriod(period):
    initMatch(0, period)
Example #6
0
def initPulse(channel, pulse_width):
    initMatch(channel, pulse_width)
Example #7
0
def initPeriod(period):
	initMatch(0, period)
Example #8
0
def initPulse(channel, pulse_width):
	initMatch(channel, pulse_width)