com.diozero.ws281xj.rpiws281x

Class WS281x

java.lang.Object

com.diozero.ws281xj.rpiws281x.WS281x

All Implemented Interfaces:

LedDriverInterface, Closeable, AutoCloseable

public class WS281x
extends Object
implements LedDriverInterface

Provides support for WS2811B / WS2812B aka Adafriut NeoPixel LEDs via a JNI wrapper around the rpi_ws281x C library.

Also see this implementation.

All colours are represented as 24bit RGB values.

Valid GPIO numbers:

• 12 / 18 (PWM)
• 21 / 31 (PCM)
• 10 (SPI)

Constructor Summary

Constructors

Constructor and Description
WS281x(int gpioNum, int brightness, int numPixels)
WS281x(int frequency, int dmaNum, int gpioNum, int brightness, int numPixels, StripType stripType)
WS281x(int frequency, int dmaNum, int gpioNum, int brightness, int numPixels, StripType stripType, int channel)

Method Summary

Modifier and Type	Method and Description
void	allOff() Turn off all pixels and render.
void	close()
int	getNumPixels()
int	getPixelColour(int pixel) Get the current colour for the specified pixel.
void	render() Push any updated colours to the LED strip.
void	setPixelColour(int pixel, int colour) Set the colour for the specified pixel.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.diozero.ws281xj.LedDriverInterface

getBlueComponent, getGreenComponent, getRedComponent, setBlueComponent, setGreenComponent, setPixelColourHSB, setPixelColourHSL, setPixelColourRGB, setRedComponent

Constructor Detail

WS281x

public WS281x(int gpioNum,
              int brightness,
              int numPixels)

Parameters:

gpioNum - GPIO pin to use to drive the LEDs.

brightness - Brightness level (0..255).

numPixels - The number of pixels connected.

WS281x

public WS281x(int frequency,
              int dmaNum,
              int gpioNum,
              int brightness,
              int numPixels,
              StripType stripType)

Parameters:

frequency - Communication frequency, 800,000 or 400,000.

dmaNum - DMA number.

gpioNum - GPIO pin to use to drive the LEDs.

brightness - Brightness level (0..255).

numPixels - The number of pixels connected.

stripType - Strip type

WS281x

public WS281x(int frequency,
              int dmaNum,
              int gpioNum,
              int brightness,
              int numPixels,
              StripType stripType,
              int channel)

Parameters:

frequency - Communication frequency, 800,000 or 400,000.

dmaNum - DMA number.

gpioNum - GPIO pin to use to drive the LEDs.

brightness - Brightness level (0..255).

numPixels - The number of pixels connected.

stripType - Strip type

channel - PWM channel

Method Detail

close

public void close()

Specified by:

close in interface LedDriverInterface

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

getNumPixels

public int getNumPixels()

Specified by:

getNumPixels in interface LedDriverInterface

render

public void render()

Description copied from interface: LedDriverInterface

Push any updated colours to the LED strip.

Specified by:

render in interface LedDriverInterface

allOff

public void allOff()

Description copied from interface: LedDriverInterface

Turn off all pixels and render.

Specified by:

allOff in interface LedDriverInterface

getPixelColour

public int getPixelColour(int pixel)

Description copied from interface: LedDriverInterface

Get the current colour for the specified pixel.

Specified by:

getPixelColour in interface LedDriverInterface

Parameters:

pixel - Pixel number.

Returns:

24-bit RGB colour value.

setPixelColour

public void setPixelColour(int pixel,
                           int colour)

Description copied from interface: LedDriverInterface

Set the colour for the specified pixel.

Specified by:

setPixelColour in interface LedDriverInterface

Parameters:

pixel - Pixel number.

colour - Colour represented as a 24bit RGB integer (0x0RGB).