Need Help with Piezo Buzzer and Ultrasonic Sensor code

Projects Programming
20

Well that figures, the old code works now too, even better than the new code haha :blush:

Clearly I had something wrong yesterday and repeatedly missed it.

EDIT:
This code works, mostly, and buzzes AND flashes an LED though it could be tweaked to be more accurate I think.

/*
 HC-SR04 Ping distance sensor]
 VCC to arduino 5v GND to arduino GND
 Echo to Arduino pin 13 Trig to Arduino pin 12
 More info at: http://goo.gl/kJ8Gl
***  edited by LarryD and KalELonRedKryptonite ***
 */


#define trigPin 12
#define echoPin 13

  int duration, distance;
  int hysteresis = 5;       // minimum acceptable change
  boolean buzzState = false;  // false = buzzer is off
  unsigned long buzzDelay;  //Time the buzzer will be On
  unsigned long buzzMilli;  //Time the buzzer went On
  int lastDistance;  // = the last read distance value


void setup() {

  Serial.begin (9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(4,OUTPUT);
  pinMode(6,OUTPUT);
  
}

void loop() {
  
  
	digitalWrite(trigPin, HIGH);
	delayMicroseconds(1000);
	digitalWrite(trigPin, LOW);
	duration = pulseIn(echoPin, HIGH);
	distance = (duration/2) / 29.1;
  
  
  
  if (distance >= 200 || distance <= 0)
  {
    Serial.println("Out of range");
  }
  else
  {
    Serial.print(distance);
    Serial.println(" cm");
  }

  // Has the distance changed significantly?
  if ((lastDistance + hysteresis) < distance || (lastDistance - hysteresis) > distance)
  {
    lastDistance = distance;
    buzzDelay = distance;
    buzzMilli = millis();
    buzzState = true; // indicate the buzzer is now on
    digitalWrite(4,HIGH);  //turn on the buzzer
    digitalWrite(6,HIGH);  //turn on the LED
  }

  if (buzzState == true && (millis() - buzzMilli >= buzzDelay))    //is time left and is the buzzer ON?
  {
    digitalWrite(4,LOW); //turn off the buzzer
    digitalWrite(6,LOW); //turn off the LED
    buzzState = false;  //indicate the buzzer is now off
  }
  

}   
   // END of loop()

I haven't done functions yet, so I'm going to read up on them first before I attempt to do the same with the newer code.