Chaser with a potentiometer on A5

/*

  Chase LEDs attached on pins 7 - 13
  Vary the speed of the chaser based on an Analog Input
  Demonstrates analog input by reading the value of a potentiometer (pot) on analog pin A5
  The valie of the pot is obtained using analogRead().

  The circuit:
   Potentiometer attached to analog input A5
   center pin of the potentiometer to the analog pin A5
   one side pin (either one) to ground
   the other side pin to +5V
  This example code is in the public domain.

  Created by David Cuartielles
  modified 30 Aug 2011
  By Tom Igoe
  modified 8 May 2014
  by Scott Fitzgerald
  modified 10 August 2016
  by rupert.russell@acu.edu.au
*/
int delayMils = 0;     // holds the value of the potentiometer
int sensorPin = A5;    // select the input pin for the potentiometer

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pins 8 - 13 as an outputs.
  pinMode(7, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(13, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {

  delayMils = analogRead(sensorPin);  // read the value of the potentiometer

  digitalWrite(7, HIGH);    // turn the LED on (HIGH is the voltage level)
  delayMils = analogRead(sensorPin);  // we want to read the value again because it may have changed
  delay(delayMils);

  digitalWrite(8, HIGH);    // turn the LED on (HIGH is the voltage level)
  delayMils = analogRead(sensorPin); // if we only read the value of the pot once per cycle the program is slower to respond to changes
  delay(delayMils);

  digitalWrite(9, HIGH);    // turn the LED on (HIGH is the voltage level)
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(10, HIGH);   // turn the LED on (HIGH is the voltage level)
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(11, HIGH);   // turn the LED on (HIGH is the voltage level)
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(12, HIGH);   // turn the LED on (HIGH is the voltage level)
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(13, HIGH);   // turn the LED on (HIGH is the voltage level)
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  // Now turn off in sequence

  digitalWrite(7, LOW);     // turn the LED off by making the voltage LOW
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(8, LOW);     // turn the LED off by making the voltage LOW
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(9, LOW);     // turn the LED off by making the voltage LOW
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(10, LOW);    // turn the LED off by making the voltage LOW
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(11, LOW);    // turn the LED off by making the voltage LOW
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(12, LOW);    // turn the LED off by making the voltage LOW
  delayMils = analogRead(sensorPin);
  delay(delayMils);

  digitalWrite(13, LOW);    // turn the LED off by making the voltage LOW
  delayMils = analogRead(sensorPin);
  delay(delayMils);
}