Class: Neotrellis::Neopixel

Inherits:
Object
  • Object
show all
Defined in:
lib/neotrellis/neopixel.rb

Overview

Neopixel is the driver of the RGB led array on the Neotrellis device.

Examples:

Turn on led #2 in red for 2 seconds with debug output

seesaw = Neotrellis::Seesaw.new(device: "/dev/i2c-1", addr: 0x2E, debug: true)
pixels = Neotrellis::Neopixel.new(seesaw)
pixels.set(1, Neotrellis::Neopixel::RED)
sleep 2
pixels.set(1, Neotrellis::Neopixel::OFF)

Turn on all leds with color #b5f115 for 2 seconds

seesaw = Neotrellis::Seesaw.new(device: "/dev/i2c-1", addr: 0x2E)
pixels = Neotrellis::Neopixel.new(seesaw)
pixels.fill(Neotrellis::Neopixel::Color.new(181, 241, 21))
sleep 2
pixels.off

Display white columns

seesaw = Neotrellis::Seesaw.new(device: "/dev/i2c-1", addr: 0x2E)
pixels = Neotrellis::Neopixel.new(seesaw, autoshow: false)
Neotrellis::Neopixel::DEFAULT_PIXEL_NUMBER.times { |i|
  pixels.set(i, Neotrellis::Neopixel::WHITE) unless i%2 == 0
}
pixels.show

Defined Under Namespace

Classes: Color

Constant Summary collapse

DEFAULT_PIXEL_NUMBER =

Default number of leds on the neotrellis 4x4 keypad

16
OFF =

Default common colors

Color.new(0, 0, 0)
RED = 
Color.new(255, 0, 0)
YELLOW = 
Color.new(255, 150, 0)
GREEN = 
Color.new(0, 255, 0)
CYAN = 
Color.new(0, 255, 255)
BLUE = 
Color.new(0, 0, 255)
PURPLE = 
Color.new(180, 0, 255)
WHITE = 
Color.new(255, 255, 255)

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(seesaw, size: DEFAULT_PIXEL_NUMBER, autoshow: true, brightness: 1.0) ⇒ Neopixel

Initialize a neopixel array driven by a seesaw chip.

Parameters:

  • seesaw (Neotrellis::SeeSaw) —

    Seesaw driver

  • size (Integer) (defaults to: DEFAULT_PIXEL_NUMBER) —

    Number of leds on the array

  • autoshow (Boolean) (defaults to: true) —

    Automatically call show() after each update

  • brightness (Float) (defaults to: 1.0) —

    Brightness of the leds. Must be between 0.0 and 1.0



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# File 'lib/neotrellis/neopixel.rb', line 73

def initialize(seesaw, size: DEFAULT_PIXEL_NUMBER, autoshow: true, brightness: 1.0)
  @seesaw = seesaw
  @pin = 3       # NeoPixel bus is on SeeSaw's pin 3
  @n = size        # Number of NeoPixels on the bus
  @bpp = 3       # 3 bytes per pixel
  @autoshow = autoshow # Automaticaly display data in buffer
  @brightness = [[brightness, 0.0].max, 1.0].min

  # Size of RGB buffer, 2 bytes for Unsigned Int Big Endian
  buf_length = [@n*@bpp].pack('S>').unpack('C*')

  @seesaw.write(NEOPIXEL_BASE, NEOPIXEL_PIN, @pin)
  @seesaw.write(NEOPIXEL_BASE, NEOPIXEL_BUF_LENGTH, *buf_length)
end

Instance Attribute Details

#autoshow ⇒ Object

Enable autoshow feature. Automatically call show() after each update.



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# File 'lib/neotrellis/neopixel.rb', line 50

def autoshow
  @autoshow
end

#brightness ⇒ Object

Get the brightness of the leds.



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# File 'lib/neotrellis/neopixel.rb', line 49

def brightness
  @brightness
end

Instance Method Details

#fill(color) ⇒ Object

Set the same color for all pixels of the array. If autoshow is false nothing will be displayed until you call the show() method.

Parameters:



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# File 'lib/neotrellis/neopixel.rb', line 119

def fill(color)
  # Disable auto show while filling the buffer
  current_autoshow = @autoshow
  @autoshow=false

  @n.times do |pixel|
    set(pixel, color)
  end

  @autoshow = current_autoshow
  show if @autoshow
end

#fill_random ⇒ Object

Set a different random color for every pixels of the array. If autoshow is false nothing will be displayed until you call the show() method.



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# File 'lib/neotrellis/neopixel.rb', line 134

def fill_random()
  # Disable auto show while filling the buffer
  current_autoshow = @autoshow
  @autoshow=false

  @n.times do |pixel|
    set(pixel, Color.new(rand(255), rand(255), rand(255)))
  end

  @autoshow = current_autoshow
  show if @autoshow
end

#off ⇒ Object

Swtich off all pixels of the array. If autoshow is false nothing will be displayed until you call the show() method.



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# File 'lib/neotrellis/neopixel.rb', line 149

def off()
  fill(OFF)
end

#set(pixel, color) ⇒ Object

Set the color of one pixel. If autoshow is false nothing will be displayed until you call the show() method.

Parameters:

  • pixel (Integer) —

    ID of the pixel in the array. Must be between 0 and size-1

  • color (Neotrellis::Neopixel::Color) —

    Color to display by the pixel



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# File 'lib/neotrellis/neopixel.rb', line 102

def set(pixel, color)
  raise "pixel out of range" unless pixel.between?(0, @n-1)

  @seesaw.write(NEOPIXEL_BASE, NEOPIXEL_BUF, *([pixel*@bpp].pack('S>').unpack('C*')), *color.to_b(brightness))
  show if @autoshow
end

#show ⇒ Object

Render the data already written in the Seesaw buffer. If autoshow is true, this method is called automatically by set() and fill()



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# File 'lib/neotrellis/neopixel.rb', line 111

def show
  @seesaw.write(NEOPIXEL_BASE, NEOPIXEL_SHOW)
end