noTone() to stop sound in Arduino - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to stop the sound on pin 8 using noTone().

Arduino

noTone([1]);

Drag options to blanks, or click blank then click option'

A8

B7

C5

D9

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different pin number than the one where the sound is playing.

Forgetting to call noTone() to stop the sound.

The noTone() function stops the sound on the specified pin. Here, pin 8 is used.

2fill in blank

medium

Complete the code to start a tone on pin 6 at 1000 Hz.

Arduino

tone([1], 1000);

Drag options to blanks, or click blank then click option'

A8

B6

C7

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong pin number.

Confusing tone() with noTone().

The tone() function starts a sound on the specified pin at the given frequency. Here, pin 6 is used.

3fill in blank

hard

Fix the error in stopping the tone on pin 9.

Arduino

noTone([1]);

Drag options to blanks, or click blank then click option'

A8

B10

C9

D7

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different pin number than 9.

Not calling noTone() at all.

To stop the tone on pin 9, you must call noTone(9);.

4fill in blank

hard

Fill both blanks to play a 500 Hz tone on pin 4 and then stop it.

Arduino

tone([1], [2]);
noTone(4);

Drag options to blanks, or click blank then click option'

A4

B500

C1000

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping pin number and frequency.

Using the wrong pin number.

Use tone(4, 500); to play a 500 Hz tone on pin 4, then noTone(4); stops it.

5fill in blank

hard

Fill all three blanks to start a 750 Hz tone on pin 3, wait 1 second, then stop the tone.

Arduino

tone([1], [2]);
delay([3]);
noTone(3);

Drag options to blanks, or click blank then click option'

A3

B750

C1000

D500

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong delay time units.

Mixing up pin number and frequency.

Start the tone on pin 3 at 750 Hz, wait 1000 milliseconds (1 second), then stop the tone.

Practice

1. What does the Arduino function noTone(pin) do?

easy

A. Changes the volume of the sound on the specified pin

B. Starts playing a tone on the specified pin

C. Stops any sound currently playing on the specified pin

D. Sets the pin as an output pin

Solution

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

   The function noTone(pin) is designed to stop any sound that is currently playing on the given pin.

2. Step 2: Differentiate from tone()

   Unlike tone(pin, frequency) which starts a sound, noTone(pin) stops it.

3. Final Answer:

   Stops any sound currently playing on the specified pin -> Option C

4. Quick Check:

   noTone() stops sound = A [OK]

Hint: Remember: noTone() always stops sound on the pin [OK]

Common Mistakes:

• Confusing noTone() with tone()
• Thinking noTone() changes volume
• Assuming noTone() starts sound

2. Which of the following is the correct syntax to stop a tone on pin 8?

easy

A. noTone8();

B. noTone();

C. noTone(pin=8);

D. noTone(8);

Solution

1. Step 1: Recall the function syntax

   The correct syntax for stopping a tone on a specific pin is noTone(pin); where pin is the pin number.

2. Step 2: Check each option

   noTone8(); uses invalid function name. noTone(pin=8); uses invalid named parameter syntax. noTone(); omits the pin number. noTone(8); is correct.

3. Final Answer:

   noTone(8); -> Option D

4. Quick Check:

   Correct syntax = B [OK]

Hint: Use noTone(pin) with pin number inside parentheses [OK]

Common Mistakes:

• Omitting the pin number
• Using incorrect function names
• Passing pin as named argument

3. What will be the output behavior of this Arduino code snippet?

tone(9, 1000);
delay(500);
noTone(9);
delay(500);

medium

A. A 1000 Hz tone plays continuously without stopping

B. A 1000 Hz tone plays for 500 ms, then stops

C. No sound plays at all

D. The tone plays for 1000 ms then stops automatically

Solution

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

   The tone(9, 1000); starts a 1000 Hz sound on pin 9. The delay(500); pauses the program for 500 milliseconds while the tone plays.

2. Step 2: Analyze noTone() and second delay()

   The noTone(9); stops the sound on pin 9. The following delay(500); pauses for another 500 ms with no sound.

3. Final Answer:

   A 1000 Hz tone plays for 500 ms, then stops -> Option B

4. Quick Check:

   tone + delay + noTone = sound stops after 500 ms [OK]

Hint: noTone(pin) stops sound immediately after delay [OK]

Common Mistakes:

• Assuming tone stops automatically after delay
• Thinking noTone restarts sound
• Ignoring delay effects

4. Identify the error in this Arduino code snippet:

tone(7, 500);
noTone();
delay(1000);

medium

A. noTone() is missing the pin number argument

B. tone() frequency 500 is invalid

C. delay() cannot be used after noTone()

D. tone() must be called after noTone()

Solution

1. Step 1: Check noTone() usage

   The function noTone() requires the pin number to specify which pin to stop sound on. Here, it is called without any argument, which is incorrect.

2. Step 2: Verify other function calls

   The tone(7, 500); is valid, and delay(1000); is allowed after noTone(). The error is only the missing pin argument in noTone().

3. Final Answer:

   noTone() is missing the pin number argument -> Option A

4. Quick Check:

   noTone() needs pin argument = C [OK]

Hint: Always pass pin number to noTone() [OK]

Common Mistakes:

• Calling noTone() without pin
• Thinking delay() is disallowed after noTone()
• Misunderstanding tone() frequency limits

5. You want to play a 440 Hz tone on pin 6 for 2 seconds, then stop the sound immediately. Which code snippet correctly achieves this?

hard

A. tone(6, 440);
delay(2000);
noTone(6);

B. noTone(6);
tone(6, 440);
delay(2000);

C. tone(6, 440);
noTone(6);
delay(2000);

D. tone(6, 440, 2000);
noTone(6);

Solution

1. Step 1: Understand tone() with duration

   tone(6, 440, 2000); plays tone for 2 seconds automatically, so calling noTone(6); immediately after stops it early, which is unnecessary.

2. Step 2: Analyze each option's order

   tone(6, 440); delay(2000); noTone(6); plays tone on pin 6 at 440 Hz, waits 2 seconds, then stops the tone with noTone(6);. This correctly plays sound for 2 seconds then stops.

3. Step 3: Check incorrect options

   noTone(6); tone(6, 440); delay(2000); stops tone before playing it. tone(6, 440); noTone(6); delay(2000); stops tone immediately after starting, so no sound lasts. tone(6, 440, 2000); noTone(6); stops tone immediately after starting with duration, which is redundant.

4. Final Answer:

   tone(6, 440); delay(2000); noTone(6); -> Option A

5. Quick Check:

   Play tone, delay, then noTone = D [OK]

Hint: Play tone, delay for duration, then call noTone(pin) [OK]

Common Mistakes:

• Calling noTone() before delay
• Stopping tone immediately after starting
• Using tone() duration with noTone() redundantly