writePWMFrequency

Writes PWM frequency to a GPIO pin

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

    Syntax

    writePWMFrequency(mypi, pinNumber, frequency)

    Description

    writePWMFrequency(mypi, pinNumber, frequency) writes the frequency 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 output a PWM signal. 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

    Frequency to assign to output pin, in Hz. The value is constrained to the minimum and maximum values that the PWM hardware can support.

    Example: 8000

    Extended Capabilities

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    Version History

    Introduced in R2016b

    See Also

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