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writePWMDutyCycle

Writes PWM duty cycle to PWM pin

    Add-On Required: This feature requires the MATLAB Support Package for Raspberry Pi Hardware add-on.

    Description

    writePWMDutyCycle(mypi, pinNumber, dutyCycle) writes the duty cycle of the output square wave to the output pin.

    The PWM uses a software implementation allowing all GPIO pins on the Raspberry Pi® hardware board to operate as a PWM pin. Each PWM pin outputs a square waveform with variable frequency, duty cycle, or average voltage. A duty cycle of 0 means the waveform is always low and a duty cycle of 1 means the waveform is always high.

    To use a PWM pin, reconfigure one of the multiple-use GPIO pins as a PWM pin.

    Examples

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    Enable PWM pin 12 and set the frequency and duty cycle.

    mypi = raspi();
    configurePin(mypi, 12, 'PWM');
    writePWMDutyCycle(mypi, 12, 0.5);
    writePWMFrequency(mypi, 12, 2000);
    

    The result is a square wave with a 50.0% duty cycle, frequency of 2000 hertz, and average voltage of 1.65 V.

    Input Arguments

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    Connection to the Raspberry Pi hardware board, specified as a raspi object.

    GPIO pin number, specified as a scalar. This argument does not accept vectors because the hardware cannot access multiple pins simultaneously.

    To get a list of valid pin numbers, enter mypi.AvailableDigitalPins.

    Example: 12

    Data Types: double

    Duty cycle of output waveform, specified as a numeric scalar between 0 and 1. This value is assigned to output pin.

    Data Types: single | double

    Extended Capabilities

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    Version History

    Introduced in R2016b