lighting_random_fade.ino

#include <SPI.h>

/* Pro Micro Test Code
   by: Nathan Seidle
   modified by: Jim Lindblom
   SparkFun Electronics
   date: January 20, 2012
   license: Public Domain - please use this code however you'd like.
   It's provided as a learning tool.

   This code is provided to show how to control the SparkFun
   ProMicro's TX and RX LEDs within a sketch. It also serves
   to explain the difference between Serial.print() and
   Serial1.print().
*/
int RXLED = 17;  // The RX LED has a defined Arduino pin

#define MAX_PIXELS 50


uint16_t _LEDs = MAX_PIXELS;
uint8_t _CSPIN = 9;
uint8_t _patterns = 4;

uint8_t _pixels[MAX_PIXELS * 3];

void setupBitmap() {
   for (int i = 0; i < _LEDs * 3; i++) {
      _pixels[i] = 0;
   }
}

void outputStrip(uint8_t r, uint8_t g, uint8_t b) {
   int index = 0, length = _LEDs * 3;
   while(index < length) {
      _pixels[index] = b;
      _pixels[index + 1] = g;
      _pixels[index + 2] = r;
      index += 3;
   }
}

void setup()
{
   pinMode(_CSPIN, OUTPUT);
   digitalWrite(_CSPIN, LOW);
   SPI.begin();

   randomSeed(analogRead(0));

   setupBitmap();

}

uint8_t aimR = 0, aimG = 0, aimB = 0;
uint8_t currentR = 0, currentG = 0, currentB = 0;

uint8_t brightness = 255;

bool aiming = true;

void loop()
{
   while (true)
   {
      if (aimR == currentR && aimG == currentG && aimB == currentB)
      {
         aimR = random(brightness);
         aimG = random(brightness);
         aimB = random(brightness);
      }
      else
      {
         if (currentR != aimR) currentR = aimR > currentR ? currentR + 1 : currentR - 1;
         if (currentG != aimG) currentG = aimG > currentG ? currentG + 1 : currentG - 1;
         if (currentB != aimB) currentB = aimB > currentB ? currentB + 1 : currentB - 1;
      }

      outputStrip(currentR, currentG, currentB);

      int i, length = _LEDs * 3;
      digitalWrite(_CSPIN, HIGH);
      SPI.setBitOrder(MSBFIRST);
      SPI.setDataMode(SPI_MODE0);
      SPI.setClockDivider(SPI_CLOCK_DIV8);


      for(i = 0; i < length; i++)
      {
         SPDR = _pixels[i];
         while(!(SPSR & (1<<SPIF)));
      }

      digitalWrite(_CSPIN, LOW);
      delay(100);
   }
}