/*
  For Loop Iteration
 
 Demonstrates the use of a for() loop.
 Lights multiple LEDs in sequence, then in reverse.
 
 The circuit:
 * LEDs from pins 2 through 7 to ground
 
 created 2006
 by David A. Mellis
 modified 30 Aug 2011
 by Tom Igoe

 modified slightly for timing PM Wiegand Jan 27 2024
 
This example code is in the public domain.
 
 http://www.arduino.cc/en/Tutorial/ForLoop
 */
 
int timer = 100;           // The higher the number, the slower the timing.
 
void setup() {
  // use a for loop to initialize each pin as an output:
  for (int thisPin = 3; thisPin < 8; thisPin++) {
    pinMode(thisPin, OUTPUT);
  }
}
 
void loop() {
  // loop from the lowest pin to the highest:
  for (int thisPin = 3; thisPin < 8; thisPin++) {
    // turn the pin on:
    digitalWrite(thisPin, HIGH);
    delay(timer);
    // turn the pin off:
    digitalWrite(thisPin, LOW);
  }
 
  // loop from the highest pin to the lowest:
  for (int thisPin = 6; thisPin >= 4; thisPin--) {
    // turn the pin on:
    digitalWrite(thisPin, HIGH);
    delay(timer);
    // turn the pin off:
    digitalWrite(thisPin, LOW);
  }
}