Playing melodies with tone() in Arduino - Mini Project: Build & Apply

Playing melodies with tone()

📖 Scenario: You have a small buzzer connected to your Arduino. You want to play a simple melody by making the buzzer beep at different notes.

🎯 Goal: Build a program that plays a short melody using the tone() function on a buzzer connected to pin 8.

📋 What You'll Learn

Create an array called notes with the frequencies of the melody notes

Create an array called durations with the length of each note in milliseconds

Use a for loop with variable i to play each note using tone()

Use noTone() to stop the buzzer between notes

Print "Melody finished!" after playing all notes

💡 Why This Matters

🌍 Real World

Playing melodies with a buzzer is common in alarms, toys, and simple music projects.

💼 Career

Understanding how to control hardware like buzzers with code is useful for embedded systems and electronics jobs.

1

Set up the melody notes

Create an integer array called notes with these exact frequencies: 262, 294, 330, 349, 392.

Arduino

# Create the notes array with the given frequencies
// Your code here

Hint

Use int notes[] = { ... }; to create the array with the exact frequencies.

2

Set up the note durations

Create an integer array called durations with these exact values: 500, 500, 500, 500, 500.

Arduino

int notes[] = {262, 294, 330, 349, 392};
// Create the durations array with the given values
// Your code here

Hint

Use int durations[] = { ... }; to create the array with the exact durations.

3

Play the melody using tone()

Write a for loop with variable i from 0 to 4 to play each note on pin 8 using tone(8, notes[i], durations[i]). After each note, add a delay of durations[i] plus 50 milliseconds. Then call noTone(8) to stop the buzzer.

Arduino

int notes[] = {262, 294, 330, 349, 392};
int durations[] = {500, 500, 500, 500, 500};

// Play each note using a for loop
// Your code here

Hint

Use a for loop from 0 to 4. Inside, call tone(8, notes[i], durations[i]), then delay(durations[i] + 50), then noTone(8).

4

Print a message after the melody

Add a Serial.begin(9600) in setup() before the loop. After the for loop, add Serial.println("Melody finished!") to print the message.

Arduino

int notes[] = {262, 294, 330, 349, 392};
int durations[] = {500, 500, 500, 500, 500};

void setup() {
  // Start serial communication
  // Your code here

  for (int i = 0; i < 5; i++) {
    tone(8, notes[i], durations[i]);
    delay(durations[i] + 50);
    noTone(8);
  }

  // Print the message
  // Your code here
}

void loop() {
  // no code needed here
}

Hint

Call Serial.begin(9600) at the start of setup(). After the loop, call Serial.println("Melody finished!").

Practice

1. What does the tone() function do in Arduino?

easy

A. It reads the value from a sensor.

B. It controls the brightness of an LED.

C. It plays a sound at a specific frequency on a speaker.

D. It sends data over the serial port.

Solution

1. Step 1: Understand the purpose of tone()

   The tone() function generates a square wave of the specified frequency on a pin, producing sound through a speaker.

2. Step 2: Compare options with function behavior

   Only It plays a sound at a specific frequency on a speaker. describes playing sound at a frequency, which matches tone() usage.

3. Final Answer:

   It plays a sound at a specific frequency on a speaker. -> Option C

4. Quick Check:

   tone() = plays sound [OK]

Hint: Remember: tone() controls sound frequency, not LEDs or sensors [OK]

Common Mistakes:

• Confusing tone() with analogWrite() for LEDs
• Thinking tone() reads sensor data
• Assuming tone() sends serial data

2. Which of the following is the correct syntax to play a 440 Hz tone on pin 8 for 500 milliseconds?

easy

A. tone(8, 440); delay(500);

B. tone(440, 8, 500);

C. tone(8, 500, 440);

D. tone(8, 440, 500);

Solution

1. Step 1: Recall tone() function parameters

   The correct order is tone(pin, frequency, duration). So pin 8, frequency 440 Hz, duration 500 ms.

2. Step 2: Check each option's parameter order

   tone(8, 440, 500); matches the correct order. tone(8, 440); delay(500); plays tone without duration, relying on delay, which is valid but not the asked syntax.

3. Final Answer:

   tone(8, 440, 500); -> Option D

4. Quick Check:

   tone(pin, freq, duration) = tone(8, 440, 500) [OK]

Hint: Remember tone(pin, frequency, duration) order [OK]

Common Mistakes:

• Swapping frequency and pin parameters
• Confusing duration with frequency
• Omitting duration but expecting timed tone

3. What will the following Arduino code do?

void setup() {
  tone(9, 262, 250);
  delay(300);
  tone(9, 294, 250);
  delay(300);
  noTone(9);
}
void loop() {}

medium

A. Play two notes (C4 and D4) on pin 9 with pauses, then stop sound.

B. Play one continuous note at 262 Hz for 800 ms.

C. Play no sound because noTone() stops all tones immediately.

D. Cause a compile error due to missing loop content.

Solution

1. Step 1: Analyze tone() and delay() calls

   The code plays 262 Hz tone for 250 ms, waits 300 ms, then plays 294 Hz tone for 250 ms, waits 300 ms.

2. Step 2: Understand noTone() effect

   noTone(9) stops any tone on pin 9 after the notes play. The loop is empty, so no repetition.

3. Final Answer:

   Play two notes (C4 and D4) on pin 9 with pauses, then stop sound. -> Option A

4. Quick Check:

   tone + delay + noTone = two notes then stop [OK]

Hint: Check tone frequency and delays to predict sound timing [OK]

Common Mistakes:

• Assuming tones play simultaneously
• Thinking noTone() stops before notes play
• Believing empty loop causes error

4. Which statement correctly describes the behavior of this code snippet:

void setup() {
  tone(7, 330);
  delay(500);
  tone(7, 349);
  delay(500);
  noTone(7);
}
void loop() {}

medium

A. The delay() calls are too short to hear the notes.

B. The second tone replaces the first (which continues until replaced), resulting in sequential notes without overlap.

C. noTone() is called too early, stopping the melody immediately.

D. tone() requires a duration parameter to work correctly.

Solution

1. Step 1: Understand tone() without duration

   Calling tone(pin, freq) plays the tone continuously until stopped or replaced by another tone() on the same pin.

2. Step 2: Analyze timing of tones and delays

   The first tone starts and plays for 500 ms during delay(). The second tone replaces it immediately, playing the new frequency for the next 500 ms. No overlap occurs.

3. Final Answer:

   The second tone replaces the first (which continues until replaced), resulting in sequential notes without overlap. -> Option B

4. Quick Check:

   tone without duration replaced by next tone() = sequential notes [OK]

Hint: tone() without duration continues until next tone() or noTone() [OK]

Common Mistakes:

• Assuming tone() stops automatically after delay
• Thinking tone() calls on same pin cause overlap
• Believing delay controls tone length without duration

5. You want to play a melody of 3 notes (262 Hz, 294 Hz, 330 Hz) each lasting 300 ms on pin 10 with 100 ms pause between notes. Which code snippet correctly achieves this?

hard

A. for (int i = 0; i < 3; i++) {
int notes[] = {262, 294, 330};
tone(10, notes[i], 300);
delay(400);
}
noTone(10);

B. int notes[] = {262, 294, 330};
for (int i = 0; i < 3; i++) {
tone(10, notes[i]);
delay(250);
noTone(10);
delay(100);
}

C. int notes[] = {262, 294, 330};
for (int i = 0; i < 3; i++) {
tone(10, notes[i], 300);
delay(250);
noTone(10);
delay(100);
}

D. int notes[] = {262, 294, 330};
for (int i = 0; i < 3; i++) {
tone(10, notes[i]);
delay(400);
}
noTone(10);

Solution

1. Step 1: Understand timing requirements

   Each note plays 300 ms, plus 100 ms pause, total 400 ms delay between notes.

2. Step 2: Check code for correct tone duration and delay

   for (int i = 0; i < 3; i++) { int notes[] = {262, 294, 330}; tone(10, notes[i], 300); delay(400); } noTone(10); uses tone with duration 300 ms and delay 400 ms, matching timing. noTone(10) after loop stops sound.

3. Step 3: Verify other options

   int notes[] = {262, 294, 330}; for (int i = 0; i < 3; i++) { tone(10, notes[i]); delay(250); noTone(10); delay(100); } calls noTone inside loop, cutting notes short. int notes[] = {262, 294, 330}; for (int i = 0; i < 3; i++) { tone(10, notes[i], 300); delay(250); noTone(10); delay(100); } delays only 250 ms, missing pause. int notes[] = {262, 294, 330}; for (int i = 0; i < 3; i++) { tone(10, notes[i]); delay(400); } noTone(10); plays tone without duration, causing overlap.

4. Final Answer:

   for (int i = 0; i < 3; i++) { int notes[] = {262, 294, 330}; tone(10, notes[i], 300); delay(400); } noTone(10); -> Option A

5. Quick Check:

   tone(duration) + delay(total note+pause) = for (int i = 0; i < 3; i++) { int notes[] = {262, 294, 330}; tone(10, notes[i], 300); delay(400); } noTone(10); [OK]

Hint: Use tone(duration) plus delay(total note+pause) for melody timing [OK]

Common Mistakes:

• Calling noTone() inside loop too early
• Using delay shorter than note+pause
• Omitting duration causing overlapping notes