Class: PiPiper::Pwm

Inherits:
Object
  • Object
show all
Includes:
PinValues
Defined in:
lib/pi_piper/pwm.rb

Overview

Represents a Pwm output on the Raspberry Pi (only GPIO18 is avaliable on header)

Constant Summary

Constants included from PinValues

PiPiper::PinValues::GPIO_FSEL_ALT0, PiPiper::PinValues::GPIO_FSEL_ALT1, PiPiper::PinValues::GPIO_FSEL_ALT2, PiPiper::PinValues::GPIO_FSEL_ALT3, PiPiper::PinValues::GPIO_FSEL_ALT4, PiPiper::PinValues::GPIO_FSEL_ALT5, PiPiper::PinValues::GPIO_FSEL_INPT, PiPiper::PinValues::GPIO_FSEL_MASK, PiPiper::PinValues::GPIO_FSEL_OUTP, PiPiper::PinValues::GPIO_HIGH, PiPiper::PinValues::GPIO_LOW, PiPiper::PinValues::GPIO_PUD_DOWN, PiPiper::PinValues::GPIO_PUD_OFF, PiPiper::PinValues::GPIO_PUD_UP, PiPiper::PinValues::PWM_MODE, PiPiper::PinValues::PWM_PIN

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options) ⇒ Pwm

Initializes a new PWM pin.

Parameters:

  • options (Hash) —

    A hash of options

Options Hash (options):

  • :pin (Fixnum) —

    The pin number to initialize. Required.



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# File 'lib/pi_piper/pwm.rb', line 15

def initialize(options)
  @options = {
    :mode => :balanced,
    :clock => 19.2.megahertz,
    :range => 1024,
    :start => true,
    :value => 0
  }.merge(options)

  unless PWM_PIN[@options[:pin]]
    raise ArgumentError, ":pin should be one of  #{PWM_PIN.keys} not #{@options[:pin]}"
  end

  unless PWM_MODE.include? @options[:mode]
    raise ArgumentError, ":mode should be one of #{PWM_MODE}, not #{@options[:mode]}"
  end

  self.value= @options.delete(:value)
  self.pin=   @options[:pin]
  self.range= @options[:range]
  self.clock= @options[:clock]

  @options.delete(:start) ? self.on : self.off
end

Instance Attribute Details

#options ⇒ Object (readonly)

Returns the value of attribute options.



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# File 'lib/pi_piper/pwm.rb', line 9

def options
  @options
end

#value ⇒ Object

Returns the value of attribute value.



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# File 'lib/pi_piper/pwm.rb', line 9

def value
  @value
end

Instance Method Details

#off ⇒ Object Also known as: stop

Stop the Pwm signal



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# File 'lib/pi_piper/pwm.rb', line 49

def off
  @on = false
  Platform.driver.pwm_mode(PWM_PIN[@options[:pin]][:channel], PWM_MODE.index(options[:mode]), 0)
end

#off? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/pi_piper/pwm.rb', line 60

def off?
  not on?
end

#on ⇒ Object Also known as: start

Start the Pwm signal



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# File 'lib/pi_piper/pwm.rb', line 41

def on
  @on = true
  Platform.driver.pwm_mode(PWM_PIN[@options[:pin]][:channel], PWM_MODE.index(options[:mode]), 1)
end

#on? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/pi_piper/pwm.rb', line 56

def on?
  @on
end