APA102 Class Reference

API for controlling APA102/DotStar RGB LED Strips. More...

Detailed Description

• ID: apa102
• Name: APA102/DotStar LED Strip
• Category: led
• Manufacturer: adafruit
• Connection: spi

APA102 LED Strips provide individually controllable LEDs through a SPI interface. For each LED, brightness (0-31) and RGB (0-255) values can be set.

    // Instantiate a strip of 30 LEDs on SPI bus 0
    upm::APA102* ledStrip = new upm::APA102(800, 0);

    // Set all LEDs to Red
    ledStrip->setAllLeds(31, 255, 0, 0);

    // Set a section (10 to 20) to blue
    ledStrip->setLeds(10, 20, 31, 0, 0, 255);

    // Set a single LED to green
    ledStrip->setLed(15, 31, 0, 255, 0);

    delete ledStrip;

Public Member Functions
	APA102 (uint16_t ledCount, uint8_t spiBus, bool batchMode=false, int8_t csn=-1)
	~APA102 ()
void	setLed (uint16_t ledIdx, uint8_t brightness, uint8_t r, uint8_t g, uint8_t b)
void	setLedBrightness (uint16_t ledIdx, uint8_t brightness)
void	setAllLeds (uint8_t brightness, uint8_t r, uint8_t g, uint8_t b)
void	setLeds (uint16_t startIdx, uint16_t endIdx, uint8_t brightness, uint8_t r, uint8_t g, uint8_t b)
void	setLedsBrightness (uint16_t startIdx, uint16_t endIdx, uint8_t brightness)
void	setLeds (uint16_t startIdx, uint16_t endIdx, uint8_t *colors)
void	setBusSpeed (int hz)
void	pushState ()

Constructor & Destructor Documentation

APA102	(	uint16_t	ledCount,
		uint8_t	spiBus,
		bool	batchMode = false,
		int8_t	csn = -1
	)

Instantiates a new APA102 LED Strip

Parameters

ledCount	Number of APA102 leds in the strip
spiBus	SPI Bus number
batchMode	(optional) Immediately write to SPI (false, default) or wait for a pushState call (true)
csn	(optional) Chip Select Pin

~APA102

(

)

APA102 destructor

Member Function Documentation

void setLed	(	uint16_t	ledIdx,
		uint8_t	brightness,
		uint8_t	r,
		uint8_t	g,
		uint8_t	b
	)

Change the color and brightness for a single led

Parameters

ledIdx	Index of the LED in the strip (0 based)
brightness	Brightness value (0-31)
r	Red component (0-255)
g	Green component (0-255)
b	Blue component (0-255)

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void setLedBrightness	(	uint16_t	ledIdx,
		uint8_t	brightness
	)

Change the brightness for a single led

Parameters

ledIdx	Index of the LED in the strip (0 based)
brightness	Brightness value (0-31)

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void setAllLeds	(	uint8_t	brightness,
		uint8_t	r,
		uint8_t	g,
		uint8_t	b
	)

Change the color and brightness for all leds

Parameters

brightness	Brightness value (0-31)
r	Red component (0-255)
g	Green component (0-255)
b	Blue component (0-255)

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void setLeds	(	uint16_t	startIdx,
		uint16_t	endIdx,
		uint8_t	brightness,
		uint8_t	r,
		uint8_t	g,
		uint8_t	b
	)

Change the color and brightness for a range of leds

Parameters

startIdx	Start index of the range of LEDs in the strip (0 based)
endIdx	End index of the range of LEDs in the strip (0 based)
brightness	Brightness value (0-31)
r	Red component (0-255)
g	Green component (0-255)
b	Blue component (0-255)

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void setLedsBrightness	(	uint16_t	startIdx,
		uint16_t	endIdx,
		uint8_t	brightness
	)

Change the brightness for a range of leds

Parameters

startIdx	Start index of the range of LEDs in the strip (0 based)
endIdx	End index of the range of LEDs in the strip (0 based)
brightness	Brightness value (0-31)

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void setLeds	(	uint16_t	startIdx,
		uint16_t	endIdx,
		uint8_t *	colors
	)

(Advanced) Manually control the colors and brightness of a range of LEDS Best used to maximize performance

Parameters

startIdx	Start index of the range of LEDs to update (0 based)
endIdx	End index of the range of LEDs to update (0 based)
colors	Pointer to an array of bytes. Each color is described as the following: B1: Brightness (224-255) B2: Blue (0-255) B3: Green (0-255) B4: Red (0-255) No check done on the boundaries

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void setBusSpeed

(

int

hz

)

Change the speed/frequency of the SPI bus Note: Slower speeds will allow driving longer strips without having to condition the clock signal with extra hardware

Parameters

hz	Desired bus speed in Hz

void pushState

(

void

)

Outputs the current LED data to the SPI bus Note: Only required if batch mode is set to TRUE

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The documentation for this class was generated from the following files:

• /iotdk/jenkins/workspace/upm-doc-stable/src/apa102/apa102.hpp
• /iotdk/jenkins/workspace/upm-doc-stable/src/apa102/apa102.cxx