Davis's LED ring code

led-ring.ino

/*
    Simple Arduino program to turn a series of pins controlling LEDs on and off
    in sequence. Each pin/LED remains on for the same period of time.
*/

/*
    Set the first and last pins, and the time for which pins will be on. These
    numbers are "inclusive" – pins X through Y, including both X and Y.
    Delay is in milliseconds.
*/
int pinStart = 2;
int pinStop = 9;
int pinDelay = 1000;    // 1000 milliseconds; i.e., 1 second

/*
    Initial setup for all the pins: set for output, and turned off.
*/
void setup() {
    for (int current_pin = pinStart; current_pin <= pinStop; current_pin++) {
        pinMode(current_pin, OUTPUT);
        digitalWrite(current_pin, LOW);
    }
}

/*
    For each pin, do the following:
    1. Turn it on
    2. Wait for the appropriate amount of time
    3. Turn it off.
*/
void loop() {
    for (int current_pin = pinStart; current_pin <= pinStop; current_pin++) {
        digitalWrite(current_pin, HIGH);
        delay(pinDelay);
        digitalWrite(current_pin, LOW);
    }
}