Meadow.Foundation.Leds.RgbPwmLed

RgbPwmLed
Status
Source code	GitHub
NuGet package

RgbPwmLed represents an RGB LED whose color is controlled by the duty-cycle of three PWM signals. Can be used both with LEDs that have been current limited with in-series resistors, or LEDs without resistors.

Controlling an RGB LED via a PWM signal is more power efficient than using a current-limiting resistor, and it provides more control; allowing thousands of different colors, as opposed to the 8 colors of non-PWM powered RGB LED.

To use without resistors, pass in the forward voltages (voltage drop) of each of the LED components to the redLedForwardVoltage, greenLedForwardVoltage, and blueLedForwardVoltage, constructor parameters, and the class will limit its output to the maximum forward voltage rating for those LEDs.

To use with an LED that has a resistor in series, pass 0.0 or TypicalForwardVoltage.ResistorLimited for the forwardVoltage parameter.

Code Example

RgbPwmLed onboardLed;

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

    onboardLed = new RgbPwmLed(
        Device.Pins.OnboardLedRed,
        Device.Pins.OnboardLedGreen,
        Device.Pins.OnboardLedBlue);

    return Task.CompletedTask;
}

public override Task Run()
{
    return TestColors();
}

public async Task TestColors()
{
    while (true)
    {
        Resolver.Log.Info("SetColor(RgbLedColors.Red);");
        onboardLed.SetColor(Color.Red);
        await Task.Delay(3000);

        Resolver.Log.Info("StartPulse();");
        await onboardLed.StartPulse();
        await Task.Delay(3000);

        Resolver.Log.Info("StartPulse(RgbLedColors.Green);");
        await onboardLed.StartPulse(Color.Green);
        await Task.Delay(3000);

        Resolver.Log.Info("SetColor(RgbLedColors.Yellow);");
        onboardLed.SetColor(Color.Yellow);
        await Task.Delay(3000);

        Resolver.Log.Info("StartPulse(RgbLedColors.Cyan, 200, 200);");
        await onboardLed.StartPulse(Color.Cyan, TimeSpan.FromMilliseconds(400));
        await Task.Delay(3000);

        await onboardLed.StopAnimation();
    }
}

Sample project(s) available on GitHub

Wiring Example