/*A sketch to demonstrate array declaration,
   initialization and referencing elements in an array.

   In other words - lots of basic and practical array stuff.
*/

//Declare an initialize an array to hold pin numbers.

byte LEDpinArray[4] = { 6, 8, 10, 12};

/*Alternately we could have written:
   byte LEDpinArray[] = { 6, 8, 10, 12}; //this is equivalent

   We might also use a variable to define the size of our array

   const byte LEDpinArraySize = 4;
   byte LEDpinArray[LEDpinArraySize] = { 6, 8, 10, 12};

   The only caveat, is that the variable MUST be a constant.
*/

//Set some delay times to for blinking the LEDs
const int longerDelayTime_ms = 1000;
const int shorterDelayTime_ms = 300;

void setup() {

  //Set the modes of the pins in the pin as array outputs
  pinMode(LEDpinArray[0], OUTPUT);
  pinMode(LEDpinArray[1], OUTPUT);
  pinMode(LEDpinArray[2], OUTPUT);
  pinMode(LEDpinArray[3], OUTPUT);

}//close setup

void loop() {

  //Turn on All the LEDs
  digitalWrite(LEDpinArray[0], HIGH);
  digitalWrite(LEDpinArray[1], HIGH);
  digitalWrite(LEDpinArray[2], HIGH);
  digitalWrite(LEDpinArray[3], HIGH);

  //Delay for a momment to see the LED stay lit
  delay(longerDelayTime_ms);

  //Turn off all the LEDs, but delay
  digitalWrite(LEDpinArray[0], LOW);
  delay(shorterDelayTime_ms);
  
  digitalWrite(LEDpinArray[1], LOW);
  delay(shorterDelayTime_ms);
  
  digitalWrite(LEDpinArray[2], LOW);
  delay(shorterDelayTime_ms);
  
  digitalWrite(LEDpinArray[3], LOW);
  delay(shorterDelayTime_ms);

}//close loop