ws2812

//////////
//
// Arduino interface for the use of ws2812 operated LEDs
// Uses Adalight protocol and is compatible with Boblight, Prismatik etc
// "Magic Word" for synchronisation is 'Ada' followed by LED High, Low and Checksum
//
///// User definitions /////
#include "FastLED.h"
// Define the number of LEDs
#define NUM_LEDS 90

// Define SPI Pin
#define PIN 12

// Baudrate, higher rate allows faster refresh rate and more LEDs (defined in /etc/boblight.conf)
#define serialRate 115200

//// End of user definitions /////

// Utilises FastSPI_LED2
#define FORCE_SOFTWARE_SPI
#define FORCE_SOFTWARE_PINS


// Adalight sends a "Magic Word" (defined in /etc/boblight.conf) before sending the pixel data
uint8_t prefix[] = {'A', 'd', 'a'}, hi, lo, chk, i;

// initialise LED-array
CRGB leds[NUM_LEDS];

void setup()
{

FastLED.addLeds<WS2812B, PIN, GRB>(leds, NUM_LEDS);

// initial RGB flash
LEDS.showColor(CRGB(255, 0, 0));
delay(500);
LEDS.showColor(CRGB(0, 255, 0));
delay(500);
LEDS.showColor(CRGB(0, 0, 255));
delay(500);
LEDS.showColor(CRGB(0, 0, 0));

Serial.begin(serialRate);
Serial.print("Ada\n"); // Send "Magic Word" string to host

}

void loop() {
// wait for first byte of Magic Word
for(i = 0; i < sizeof prefix; ++i) {
waitLoop: while (!Serial.available()) ;;
// Check next byte in Magic Word
if(prefix[i] == Serial.read()) continue;
// otherwise, start over
i = 0;
goto waitLoop;
}

// Hi, Lo, Checksum

while (!Serial.available()) ;;
hi=Serial.read();
while (!Serial.available()) ;;
lo=Serial.read();
while (!Serial.available()) ;;
chk=Serial.read();

// if checksum does not match go back to wait
if (chk != (hi ^ lo ^ 0x55))
{
i=0;
goto waitLoop;
}

memset(leds, 0, NUM_LEDS * sizeof(struct CRGB));
// read the transmission data and set LED values
for (uint8_t i = 0; i < NUM_LEDS; i++) {
byte r, g, b;
while(!Serial.available());
r = Serial.read();
while(!Serial.available());
g = Serial.read();
while(!Serial.available());
b = Serial.read();
leds[i].r = r;
leds[i].g = g;
leds[i].b = b;
}
// shows new values
FastLED.show();
}