|Since||Origin / Contributor||Maintainer||Source|
|2016-01-26||Robert Foss||Robert Foss||apa102.c|
This module provides Lua access to APA102 RGB LEDs which are similar in function to the common WS2812 addressable LEDs.
DotStar LEDs are 5050-sized LEDs with an embedded micro controller inside the LED. You can set the color/brightness of each LED to 24-bit color (8 bits each red green and blue). Each LED acts like a shift register, reading incoming color data on the input pins, and then shifting the previous color data out on the output pin. By sending a long string of data, you can control an infinite number of LEDs, just tack on more or cut off unwanted LEDs at the end.
Send ABGR data in 8 bits to a APA102 chain.
apa102.write(data_pin, clock_pin, string)
data_pinany GPIO pin 0, 1, 2, ...
clock_pinany GPIO pin 0, 1, 2, ...
stringpayload to be sent to one or more APA102 LEDs. It should be composed from a ABGR quadruplet per element.
A1the first pixel's Intensity channel (0-31)
B1the first pixel's Blue channel (0-255)
G1the first pixel's Green channel (0-255)
R1the first pixel's Red channel (0-255) ... You can connect a lot of APA102 ...
R2are the next APA102s Intensity, Blue, Green and Red channel parameters
a = 31 b = 0 g = 0 r = 255 led_abgr = string.char(a, b, g, r, a, b, g, r) apa102.write(2, 3, leds_abgr) -- turn two APA102s to red, connected to data_pin 2 and clock_pin 3