PWM Manager

Reqirements

  • The PWMManager class requires pinctrl to be installed. To install the library, run the following command:

    curl -sSL https://raw.githubusercontent.com/Rylan-Meilutis/gpio_manager/refs/heads/main/install-utils.sh -o install-utils.sh && sudo bash install-utils.sh && rm install-utils.sh

    Without the library installed, the pin may not be setup for hardware PWM, and thus the PWM signal may not be generated.

Enums

The following enums are used in this class. See the Enums page for details:

  • LogicLevel

PWMManager Class

The PWMManager class provides methods to control PWM channels.

Methods

  • Constructor:

    Initializes the PWMManager class, the PWM pins are in an unknown state until they are setup.

    Example:

    PWM_manager = gpio_manager.PWMManager()
  • setup_pwm_channel:
    Sets up a PWM channel with the specified parameters.

    The value of frequency_hz and duty_cycle overwrites period_ms and pulse_width_ms if they are set. If neither frequency_hz and duty_cycle nor period_ms and pulse_width_ms are set, the default value of 1000 hz and a duty_cycle of 0 are used.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    • frequency_hz (Optional[float]): Frequency in Hertz.

    • duty_cycle (Optional[float]): Duty cycle as a percentage (0-100).

    • period_ms (Optional[float]): Period in milliseconds.

    • pulse_width_ms (Optional[float]): Pulse width in milliseconds.

    • logic_level (Optional[LogicLevel]): Logic level of the PWM signal (HIGH, LOW).

    Example:

    PWM_manager.setup_pwm_channel(channel_num=0, frequency_hz=1000, duty_cycle=50)
PWM_manager.setup_pwm_channel(channel_num=1, period_ms=1000, pulse_width_ms=500)
  • start_pwm_channel:

    Starts the PWM signal on the specified channel.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    Example:

    PWM_manager.start_pwm_channel(channel_num=0)
  • stop_pwm_channel:

    Stops the PWM signal.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    Example:

    PWM_manager.stop_pwm_channel(channel_num=0)
  • reset_pwm_channel:

    Resets the PWM channel.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    Example:

    PWM_manager.reset_pwm_channel(channel_num=0)
  • set_duty_cycle:

    Sets the duty cycle for the specified PWM channel.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    • duty_cycle (float): Duty cycle as a percentage (0-100).

    Example:

    PWM_manager.set_duty_cycle(channel_num=0, duty_cycle=75)
  • set_frequency:

    Sets the frequency for the specified PWM channel.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    • frequency_hz (float): Frequency in Hertz.

    Example:

    PWM_manager.set_frequency(channel_num=0, frequency_hz=2000)
  • get_frequency:

    Gets the current frequency of the specified PWM channel.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    Returns: - (float): The current frequency in Hertz.

    Example:

    current_frequency = PWM_manager.get_frequency(channel_num=0)
  • get_duty_cycle:

    Gets the current duty cycle of the specified PWM channel.

    Parameters:

    • channel_num (int): The PWM channel number (0 or 1).

    Returns: - (float): The current duty cycle as a percentage (0-100).

    Example:

    current_duty_cycle = PWM_manager.get_duty_cycle(channel_num=0)
  • cleanup:

    Cleans up all PWM channels.

    Example:

    PWM_manager.cleanup()