5.4.11 Project 6.1 Control SK6812

1. Description

The atmosphere lamp of smart home is 4 SK6812RGB LEDs. RGB LED belongs to a simple luminous module, which can adjust the color to bring out the lamp effect of different colors. Furthermore, it can be widely used in buildings, bridges, roads, gardens, courtyards, floors and other fields of decorative lighting and venue layout, Christmas, Halloween, Valentine’s Day, Easter, National Day as well as other festivals during the atmosphere and other scenes.

In this experiment, we will make various lighting effects.

2. Component Knowledge

From the schematic diagram, we can see that these four RGB LEDs are all connected in series. In fact, no matter how many they are, we can use a pin to control a RGB LED and let it display any color. Each RGBLED is an independent pixel, composed of R, G and B colors, which can achieve 256 levels of brightness display and complete the full true color display of 16777216 colors.

What’s more, the pixel point contains a data latch signal shaping amplifier drive circuit and a signal shaping circuit, which effectively ensures the color of the pixel point light is highly consistent.

3. Pin

SK6812	26
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4. Test Code

#include <Adafruit_NeoPixel.h>
#ifdef __AVR__
 #include <avr/power.h>                              // Required for 16 MHz Adafruit Trinket
#endif
#define LED_PIN    26                                // Which pin on the Arduino is connected to the NeoPixels?
#define LED_COUNT 4                                  // How many NeoPixels are attached to the Arduino?
Adafruit_NeoPixel strip(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800); // Declare our NeoPixel strip object:

void setup() {
#if defined(__AVR_ATtiny85__) && (F_CPU == 16000000)
  clock_prescale_set(clock_div_1);                   // These lines are specifically to support the Adafruit Trinket 5V 16 MHz.
#endif
  strip.begin();                                     // INITIALIZE NeoPixel strip object (REQUIRED)
  strip.show();                                      // Turn OFF all pixels ASAP
  strip.setBrightness(50);                           // Set BRIGHTNESS to about 1/5 (max = 255)
}

void loop() {
  colorWipe(strip.Color(255,   0,   0), 50);         // Red
  colorWipe(strip.Color(  0, 255,   0), 50);         // Green
  colorWipe(strip.Color(  0,   0, 255), 50);         // Blue

  theaterChase(strip.Color(127, 127, 127), 50);      // White, half brightness
  theaterChase(strip.Color(127,   0,   0), 50);      // Red, half brightness
  theaterChase(strip.Color(  0,   0, 127), 50);      // Blue, half brightness

  rainbow(10);                                       // Flowing rainbow cycle along the whole strip
  theaterChaseRainbow(50);                           // Rainbow-enhanced theaterChase variant
}

void colorWipe(uint32_t color, int wait) {
  for(int i=0; i<strip.numPixels(); i++) {           // For each pixel in strip...
    strip.setPixelColor(i, color);                   // Set pixel's color (in RAM)
    strip.show();                                    // Update strip to match
    delay(wait);                                     // Pause for a moment
  }
}

void theaterChase(uint32_t color, int wait) {
  for(int a=0; a<10; a++) {                         // Repeat 10 times...
    for(int b=0; b<3; b++) {                        // 'b' counts from 0 to 2...
      strip.clear();                                // Set all pixels in RAM to 0 (off)
      for(int c=b; c<strip.numPixels(); c += 3) {    // 'c' counts up from 'b' to end of strip in steps of 3...
        strip.setPixelColor(c, color);               // Set pixel 'c' to value 'color'
      }
      strip.show();                                 // Update strip with new contents
      delay(wait);                                  // Pause for a moment
    }
  }
}

void rainbow(int wait) {
  for(long firstPixelHue = 0; firstPixelHue < 5*65536; firstPixelHue += 256) {
    for(int i=0; i<strip.numPixels(); i++) {        // For each pixel in strip...
      int pixelHue = firstPixelHue + (i * 65536L / strip.numPixels());
      strip.setPixelColor(i, strip.gamma32(strip.ColorHSV(pixelHue)));
    }
    strip.show();                                   // Update strip with new contents
    delay(wait);                                   // Pause for a moment
  }
}

void theaterChaseRainbow(int wait) {
  int firstPixelHue = 0;                           // First pixel starts at red (hue 0)
  for(int a=0; a<30; a++) {                        // Repeat 30 times...
    for(int b=0; b<3; b++) {                       // 'b' counts from 0 to 2...
      strip.clear();                               // Set all pixels in RAM to 0 (off)
      for(int c=b; c<strip.numPixels(); c += 3) {  // 'c' counts up from 'b' to end of strip in increments of 3...
        int      hue   = firstPixelHue + c * 65536L / strip.numPixels();
        uint32_t color = strip.gamma32(strip.ColorHSV(hue)); // hue -> RGB
        strip.setPixelColor(c, color);             // Set pixel 'c' to value 'color'
      }
      strip.show();                               // Update strip with new contents
      delay(wait);                               // Pause for a moment
      firstPixelHue += 65536 / 90;               // One cycle of color wheel over 90 frames
    }
  }
}

5. Test Result

The atmosphere lamps of the smart home will display a variety of colors and light effects.