fade

gistfile1.txt

/*Fade Up*/
          for(byte i=1; i<100; i++) {
            byte on  = i;
            byte off = 100-on;
            for( byte a=0; a<100; a++ ) {
              digitalWrite(led, HIGH);
              delayMicroseconds(on);
              digitalWrite(led, LOW);
              delayMicroseconds(off);
            }
          }
            /*Fade Down*/
            for(byte i=1; i<100; i++) {
            byte on  = 100-i;
            byte off = i;
            for( byte a=0; a<100; a++ ) {
              digitalWrite(led, HIGH);
              delayMicroseconds(on);
              digitalWrite(led, LOW);
              delayMicroseconds(off);
            }  
           }