Playing melodies with tone() in Arduino - Step-by-Step Execution

Concept Flow - Playing melodies with tone()

Start

↓

Define notes and durations

↓

Loop through each note

↓

Call tone() to play note

↓

Delay for note duration

↓

Stop tone()

↓

Next note or End

↓

Repeat or Stop

The program defines notes and durations, then plays each note using tone(), waits, stops the tone, and moves to the next note.

Execution Sample

Arduino

int melody[] = {262, 294, 330};
int duration[] = {500, 500, 500};
for (int i=0; i<3; i++) {
  tone(8, melody[i]);
  delay(duration[i]);
  noTone(8);
}

This code plays three notes (C4, D4, E4) on pin 8, each for 500 milliseconds.

Execution Table

Step	i	melody[i]	Action	Output/Effect
1	0	262	tone(8, 262)	Pin 8 plays note C4 (262 Hz)
2	0	262	delay(500)	Wait 500 ms while note plays
3	0	262	noTone(8)	Stop tone on pin 8
4	1	294	tone(8, 294)	Pin 8 plays note D4 (294 Hz)
5	1	294	delay(500)	Wait 500 ms while note plays
6	1	294	noTone(8)	Stop tone on pin 8
7	2	330	tone(8, 330)	Pin 8 plays note E4 (330 Hz)
8	2	330	delay(500)	Wait 500 ms while note plays
9	2	330	noTone(8)	Stop tone on pin 8
10	3	N/A	Loop ends	All notes played, melody finished

💡 i reaches 3, loop condition i<3 is false, melody playback ends

Variable Tracker

Variable	Start	After 1	After 2	After 3	Final
i	undefined	0	1	2	3
melody[i]	N/A	262	294	330	N/A

Key Moments - 3 Insights

Why do we call noTone() after delay()?

Because tone() starts playing the note and keeps playing until stopped. delay() waits while the note plays, then noTone() stops the sound. See execution_table rows 2 and 3.

What happens if we forget noTone()?

The last note will keep playing continuously because tone() never stops. The program won't move on properly. This is why noTone() is important after each note.

Why do we use a loop to play the melody?

The loop lets us play each note in order without repeating code. It goes through melody[] and duration[] arrays step by step, as shown in execution_table steps 1 to 9.

Visual Quiz - 3 Questions

Look at the execution_table, what is the frequency played at step 4?

A 262 Hz

B 330 Hz

C 294 Hz

D No frequency played

💡 Hint

Check the 'melody[i]' value at step 4 in the execution_table.

At which step does the program stop playing the last note?

A Step 9

B Step 8

C Step 10

D Step 7

💡 Hint

Look for noTone(8) call for the last note in execution_table.

If we increase delay duration to 1000 ms, how does execution_table change?

A Tone frequencies change

B Delay steps show 1000 ms instead of 500 ms

C Loop runs fewer times

D noTone() calls are removed

💡 Hint

Check the 'Action' and 'Output/Effect' columns for delay() steps in execution_table.

Concept Snapshot

Use tone(pin, frequency) to play a note on a pin.
Use delay(duration) to wait while note plays.
Use noTone(pin) to stop the note.
Loop through arrays of notes and durations to play melodies.
Each note plays until noTone() stops it.
This creates simple melodies on Arduino.

Full Transcript

This example shows how to play a melody on Arduino using tone(). We define arrays for notes and durations. A loop goes through each note, calls tone() to start playing, waits with delay(), then calls noTone() to stop. This repeats for all notes. The execution table shows each step: playing a note, waiting, stopping, then moving to the next. Variables i and melody[i] change as the loop runs. Key points: noTone() stops the sound, delay() controls note length, and looping plays all notes in order. The quiz checks understanding of frequencies played, when notes stop, and effects of changing delay.