char LedPin[]={3, 7, 9, 10, 11, 12 , 13};
char i, x, y;
int t1;
void setup() {
  for(i=0; i<7; i++)   {
    pinMode(LedPin[i], OUTPUT);
  }
  Serial.begin(9600);
}
void loop() {
  t1=analogRead(0);
  for(x=0; x<7; x++)   {
    digitalWrite(LedPin[x], HIGH);
  	delay(t1);
  	digitalWrite(LedPin[x], LOW);
  	delay(10);
  }
  for(y=6; y>0; y--)   {
    digitalWrite(LedPin[y], HIGH);
  	delay(t1);
  	digitalWrite(LedPin[y], LOW);
  	delay(10); 
  }
  Serial.println("Turn potentiometer");
  Serial.println();
  Serial.print("Blink time (ms): ");
  Serial.println(t1); 
}