Meadow.Foundation.Audio.PiezoSpeaker

PiezoSpeaker
Status
Source code	GitHub
NuGet package

The PiezoSpeaker class represents a piezoelectric speaker that can be used to generate tones across a range of frequencies. They typically perform well between 1-5kHz but may go as high as 100kHz. PiezoSpeaker Implements IToneGenerator.

The positive pin of the piezo speaker connects to a pulse width modulation (PWM) capable pin on the Meadow and the negative pin connects to common/ground. A resistor can be placed in-line to reduce volume.

Code Example

protected PiezoSpeaker piezoSpeaker;

public override Task Initialize()
{
    Resolver.Log.Info("Initializing...");

    piezoSpeaker = new PiezoSpeaker(Device.CreatePwmPort(Device.Pins.D05, new Frequency(100, Frequency.UnitType.Hertz)));

    return Task.CompletedTask;
}

public override async Task Run()
{
    for (int i = 0; i < 5; i++)
    {
        Resolver.Log.Info("Playing A major triad starting at A4");
        await piezoSpeaker.PlayTone(new Frequency(440, Frequency.UnitType.Hertz), TimeSpan.FromMilliseconds(500)); //A
        await piezoSpeaker.PlayTone(new Frequency(554.37f, Frequency.UnitType.Hertz), TimeSpan.FromMilliseconds(500)); //C#
        await piezoSpeaker.PlayTone(new Frequency(659.25f, Frequency.UnitType.Hertz), TimeSpan.FromMilliseconds(500)); //E

        await Task.Delay(2500);
    }
}

Sample project(s) available on GitHub

Wiring Example