Controlling Buzzer using Analog input

Ok, so I try out your code and it didn't work. It said something about the buzzer not being declared. I went ahead and declared with "int buzzer = 11" but still didn't work.

I've then tried to put the part of your code that made sense to me to be altered and finally managed to make it work. Success.

The next phase of my project is having a second alarm for a different distance / voltage. For example from 1st Alarm - from 3v to 1.5v, 2nd Alarm - everything below 1.5V. How would you code this condition?

Thank you so much for your help

Here's the code that made it happen:

int buzzer = 11;
// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
  pinMode(buzzer, OUTPUT);
}




// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0:
  int sensorValue = analogRead(A0);
  // print out the value you read:
  float voltage = sensorValue * (3.3 / 1023.0);
  if  (voltage < 1.5)
       { 
        tone(buzzer, 700);
        delay(150);
       }    
  //delay(500);  
  noTone(buzzer); 
  delay(150);  
  Serial.println(voltage); 
  //delay(1);        // delay in between reads for stability 
}

Thanks so much for your input. I’ll test the code tomorrow and will give you the feedback of how it went. Fingers crossed    

rictrajano

Thanks for the code, and I've now discovered the tone command.

Tone drives the appropriate pin (buzzer) with a 50% duty cycle at the desired frequency.

You wish to generate this tone when the analogue reading is greater than 2 (line 16), but you're also driving the pin into a state as an output.

I suggest trying this code instead.

// the loop routine runs over and over again forever:  
void loop() {  
// read the input on analog pin 0:  
int sensorValue = analogRead(A0);  
// print out the value you read:  
float voltage = sensorValue * (3.3 / 1023.0);  
if  (voltage > 2) 
     {
         tone(buzzer, 700, 500); 
     }  
   //delay(500);  
  noTone(buzzer); 
  delay(500);  
  Serial.println(voltage); 
  //delay(1);        // delay in between reads for stability 
}

I've removed the 500 mS delay and used it for the tone duration instead.

I also removed the delay(1) as you already have a 500 mS delay in the loop at Line13.

Note that with the 500mS tone and the delay the loop runs at 1 second, so you'll need to change your methods to suit this

at 5m would start to buzz every half a second in a certain frequency (700Hz) and when it would reach 2m would buzz every 1/8 of a second

However lets get it playing a note as you expect before we tackle the next part.

I haven't tried the code and I haven't got an Arduino in front of me, but this should help you to sort out what you are after.

Cheers

Mark

So this is the code that I've been working on. I got some of it in the Arduino examples and the other in a schematics for a buzzer on youtube. I then tried to put it together using some conditions but apparently I'm not the code genius that I thought I was after watching some youtube videos on coding

Please don't be too harsh on me

int buzzer = 11;
// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
  pinMode(buzzer, OUTPUT);
}


// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0:
  int sensorValue = analogRead(A0);
  // print out the value you read:
  float voltage = sensorValue * (3.3 / 1023.0);
  if  (voltage > 2) digitalWrite(buzzer, HIGH);
  else digitalWrite(buzzer, LOW);
  tone(buzzer, 700);
  delay(500);
  noTone(buzzer);
  delay(500);
  Serial.println(voltage);
  delay(1);        // delay in between reads for stability 
}

@

Post the code (select it in the post, then use the >> symbol and choose Syntax Highlighting and then C++)

It will give us a better idea of what might be causing it.

Mark