See also

You can find out more information using the following references:

• Examples of changing the frequency when calling the play_tone method can be found at https://learn.adafruit.com/circuitpython-made-easy-on-circuit-playground-express/play-tone.
• A microcontroller project that makes a siren alarm sound can be found at https://www.instructables.com/id/How-to-Make-a-Siren-Using-Arduino/.