knightrider.cpp

/*
 *  Project week 5: Introduction to the Arduino
 *    Night Rider-like fading LEDs
 *
 *  Martijn Reening (s1523996)
 */

#include <SoftPWM.h>

/* Define the fade time in milliseconds */
#define FADE_TIME 60
#define GLOW_TIME (FADE_TIME * 3)

/* Map the pins in order and calculate the pin count for later use */
int pins[] = { 12, 11, 10, 9, 8, 7, 6, 5 };
int pin_count = sizeof(pins) / sizeof(int);

/* Generic counter variable */
static volatile int i;

void setup() {
    /* Initialize the SoftPWM library */
    SoftPWMBegin();
    
    /* Initialize all of the pins and set the fade time */
    for(i=0; i<pin_count; ++i) {
        SoftPWMSet(pins[i], 0);
        SoftPWMSetFadeTime(pins[i], 0, GLOW_TIME);
    }
}

void loop() {
    /* Fade in each LED in order of pins, and fade out when it's on */
    for (i=0; i<pin_count; ++i) {
        SoftPWMSet(pins[i], 255);
        delay(FADE_TIME);
        SoftPWMSet(pins[i], 0);
    }

    /* Wait until the last LED is fully on */    
    delay(FADE_TIME);
    
    /* Same as above, but in reverse order */
    for (--i; i>=0; --i) {
        SoftPWMSet(pins[i], 255);
        delay(FADE_TIME);
        SoftPWMSet(pins[i], 0);
    }
    
    /* Wait until the last LED is fully on */   
    delay(FADE_TIME);
}