/******************************************************************************

|                           RGB Light                                          |

******************************************************************************/

#define RED        (2)

#define GREEN      (1)

#define BLUE       (16)

 

#define CONFIG_RED     100

#define CONFIG_GREEN   100

#define CONFIG_BLUE    100

 

volatile signed char red = 0;

volatile signed char blue = 0;

volatile signed char green = 0;

volatile signed char counter = 0;

 

void changecolour(signed char, signed char, signed char, unsigned long int);

 

 

void main(void)

{

   OPTION_REG = 0b11011000;

   INTCON = 0b10100000;

   TRISB = 0;

   PORTB = 0;

   

   while(1)

   {

       changecolour(100,0,0,1000);

       changecolour(0,100,0,1000);

       changecolour(0,0,100,1000);

   }

}

 

signed char calc_change(signed char input1, signed char input2)

{

   signed char temp;

   if(input1 < input2)

      temp = -1;

   else

      temp = 1;

 

   temp *= 100 / input1;

   return temp;

}

 

void changecolour(signed char newred, signed char newgreen, signed char newblue, unsigned long int tottime)

{

   signed char j;

   signed char tempred, stepred;

   signed char tempgreen, stepgreen;

   signed char tempblue, stepblue;

   unsigned long int i;

 

   tempred = newred - red;

   stepred = calc_change(tempred, red);

   tempred = stepred;

   

   tempgreen = newgreen - green;

   stepgreen = calc_change(tempgreen, green);

   tempgreen = stepgreen;

   

   tempblue = newblue - blue;

   stepblue = calc_change(tempblue, blue);

   tempblue = stepblue;

   

   for(j=1 ; j<=100 ; j++)

   {

      for(i=0 ; i < (tottime / 100); i++)

         Delay_us(1);

         

      if(tempred >= j)

      {

         if(newred > red)

            red++;

         else

            red--;

         tempred += stepred;

      }

      if(tempgreen >= j)

      {

         if(newgreen > green)

            green++;

         else

            green--;

         tempgreen += stepgreen;

      }

      if(tempblue >= j)

      {

         if(newblue > blue)

            blue++;

         else

            blue--;

         tempblue += stepblue;

      }

   }

}

 

void interrupt(void)

{

   unsigned int temp;

   INTCON &= ~0b00000100;

   TMR0 = 0x20;

   if(++counter > 100)

      counter = 1;

 

   if(red > 100)  red = 100;

   if(green > 100) green = 100;

   if(blue > 100) blue = 100;

 

   //temp = (red * CONFIG_RED) / 100;

   temp = red;

   if(temp >= counter)

      PORTB |= RED;

   else

      PORTB &= ~RED;

 

   //temp = (green * CONFIG_GREEN) / 100;

   temp = green;

   if(temp >= counter)

      PORTB |= GREEN;

   else

      PORTB &= ~GREEN;

 

   //temp = (blue * CONFIG_BLUE) / 100;

   temp = blue;

   if(temp >= counter)

      PORTB |= BLUE;

   else

      PORTB &= ~BLUE;

}