GPIO Manager

Enums

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

• InternPullResistorState

• PinState

• LogicLevel

• TriggerEdge

GPIOManager Class

The GPIOManager class provides methods to manage GPIO pins, register callbacks, and handle PWM signals.

Methods

• Constructor:

  Initializes the GPIOManager class. The GPIO will be in an unknown state until a pin is set up.

  Example:

  GPIO_manager = gpio_manager.GPIOManager()
  

• add_input_pin:

  Sets a pin as an input pin.

  Parameters:

  • pin_num (int): The GPIO pin to configure as input.

  • pull_resistor_state (InternPullResistorState): Pull resistor state (PULLUP, PULLDOWN, EXTERNAL, AUTO). Default: AUTO.

  • logic_level (LogicLevel): The logic level of the pin (HIGH, LOW). Default: HIGH.

  • reset_on_exit (bool): Whether to reset the pin on exit. Default: True. Calling cleanup() or reset() will also ensure that the pin is reset to its default state.

  Example:

  GPIO_manager.add_input_pin(pin_num=17, pull_resistor_state=gpio_manager.InternPullResistorState.PULLUP, logic_level=gpio_manager.LogicLevel.HIGH)
  GPIO_manager.add_input_pin(pin_num=18)
  

• assign_callback:

  Assigns a callback function to an input pin. If enabled, TriggerTime is a float representing the time the trigger occurred since unix time epoch. TriggerEdge is an enum representing the edge that triggered the callback (gpio_manager.TriggerEdge.[RISING, FALLING]). You can assign multiple callbacks to the same pin. (Note) The debounce time is

  only assigned the first time a callback is assigned to a pin. If you want to change the debounce time, you must unassign the callback and reassign it with the new debounce time.

  Parameters:

  • pin_num (int): The GPIO pin.

  • callback (Callable): The function to invoke on pin change.

  • trigger_edge (Optional[TriggerEdge]): The edge trigger (RISING, FALLING, BOTH). Default: BOTH.

  • debounce_time_ms (Optional[float]): Debounce time in milliseconds. Default: 2.

  • args (Optional[Tuple]): Arguments to pass to the callback function. Default: None.

  • include_trigger_time (Optional[bool]): Whether to include the trigger time in the callback arguments. Default: False. (Note: parameter will be the first one passed to the function.)

  • include_previous_state (Optional[bool]): Whether to include the previous state in the callback arguments. Default: False. (Note: parameter will be the second one passed to the function if include_trigger_time is true. Otherwise, it will be the first parameter.)

  Example:

  GPIO_manager.assign_callback(pin_num=15, callback=button_callback, trigger_edge=gpio_manager.TriggerEdge.FALLING, args=(15,), debounce_time_ms=50)
  GPIO_manager.assign_callback(pin_num=16, callback=button_callback, trigger_edge=gpio_manager.TriggerEdge.RISING)
  

  Example Callback:

  def button_callback(trigger_time: float, edge: gpio_manager.TriggerEdge, pin_num: int):
      if edge == gpio_manager.TriggerEdge.RISING:
          print(f"Button {pin_num} triggered at {trigger_time} on a rising edge")
      else:
          print(f"Button {pin_num} triggered at {trigger_time} on a falling edge")
  

  This callback was setup with the following function call to trigger on pin 15:

  GPIO_manager.assign_callback(15, button_callback, gpio_manager.TriggerEdge.BOTH, args=(15,), include_trigger_time=True, include_trigger_edge=True)
  

• add_output_pin:

  Sets up an output pin.

  Parameters:

  • pin_num (int): The GPIO pin to configure as output.

  • pin_state (PinState): Initial state of the pin (HIGH, LOW). Default: LOW.

  • logic_level (LogicLevel): Logic level of the pin (HIGH, LOW). Default: HIGH.

  • reset_on_exit (bool): Whether to reset the pin on exit. Default: True. Calling cleanup() or reset() will also ensure that the pin is reset to its default state.

  Example:

  GPIO_manager.add_output_pin(pin_num=12, pin_state=gpio_manager.PinState.LOW, logic_level=gpio_manager.LogicLevel.HIGH)
  GPIO_manager.add_output_pin(pin_num=11)
  

• set_reset_on_exit:

  Sets the reset_on_exit flag for the given pin. If set the pin will be reset to its default state when the pin is no longer in use. Calling cleanup() or reset() will also ensure that the pin is reset to its default state.

  Parameters:

  • pin_num (int): The GPIO pin.

  • reset_on_exit (bool): Whether to reset the pin to its default state when it is no longer in use.

  Example:

  GPIO_manager.set_reset_on_exit(pin_num=12, reset_on_exit=False)
  

• set_output_pin:

  Sets the state of an output pin.

  Parameters:

  • pin_num (int): The GPIO pin.

  • pin_state (PinState): Desired pin state (HIGH, LOW).

  Example:

  GPIO_manager.set_output_pin(pin_num=12, pin_state=gpio_manager.PinState.HIGH)
  

• get_pin:

  Polls the current state of an input pin.

  Parameters:

  • pin_num (int): The GPIO pin to get.

  Returns: - (PinState): The current state of the pin.

  Example:

  current_state = GPIO_manager.get_pin(pin_num=12)
  

• unassign_callback:

  Unassigns the provided callback from an input pin.

  Parameters:

  • pin_num (int): The GPIO pin whose callback is to be reset.

  • callback (Callable): The function to remove from the pin.

  Example:

  GPIO_manager.unassign_callback(pin_num=15, callback=button_callback)
  

• unassign_callbacks:

  Unassigns all callbacks from an input pin.

  Parameters:

  • pin_num (int): The GPIO pin whose callback is to be reset.

  Example:

  GPIO_manager.unassign_callback(pin_num=15)
  

• wait_for_edge:

  Waits for an edge trigger on an input pin.

  Parameters:

  • pin_num (int): The GPIO pin.

  • trigger_edge (Optional[TriggerEdge]): Trigger type (RISING, FALLING, BOTH). Default: BOTH.

  • timeout_ms (Optional[float]): Timeout in milliseconds. Default: None.

  • debounce_ms (Optional[float]): Debounce time in milliseconds. Default: 2.

  Example:

  GPIO_manager.wait_for_edge(pin_num=15, trigger_edge=gpio_manager.TriggerEdge.FALLING, timeout_ms=1000)
  GPIO_manager.wait_for_edge(pin_num=16, trigger_edge=gpio_manager.TriggerEdge.RISING)
  

• setup_pwm:

  Sets up a PWM signal on the given pin. The pin must be set up as an output pin before calling this function.

  (Note) frequency_hz and period_ms are mutually exclusive. duty_cycle and pulse_width_ms are also mutually exclusive. If frequency_hz is set, period_ms will be ignored. If duty_cycle is set, pulse_width_ms will be ignored.

  Parameters:

  • pin_num (int): The GPIO pin.

  • frequency_hz (Optional[float]): Frequency of the PWM signal in Hertz. Default: 1000.

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

  • period_ms (Optional[float]): PWM period in milliseconds. Default: 1.

  • pulse_width_ms (Optional[float]): Pulse width in milliseconds. Default: 0.

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

  Example:

  GPIO_manager.setup_pwm(pin_num=12, frequency_hz=1000, duty_cycle=50)
  GPIO_manager.setup_pwm(pin_num=11, period_ms=1000, pulse_width_ms=500)
  

• set_pwm_duty_cycle:

  Sets the PWM signal’s duty cycle.

  Parameters:

  • pin_num (int): The GPIO pin.

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

  Example:

  GPIO_manager.set_pwm_duty_cycle(pin_num=12, duty_cycle=75)
  

• set_pwm_frequency:

  Sets the PWM signal’s frequency.

  Parameters:

  • pin_num (int): The GPIO pin.

  • frequency_hz (float): Frequency in Hertz.

  Example:

  GPIO_manager.set_pwm_frequency(pin_num=12, frequency_hz=1000)
  

• start_pwm:

  Starts the PWM signal on the specified pin.

  Parameters:

  • pin_num (int): The GPIO pin.

  Example:

  GPIO_manager.start_pwm(pin_num=12)
  

• stop_pwm:

  Stops the PWM signal.

  Parameters:

  • pin_num (int): The GPIO pin.

  Example:

  GPIO_manager.stop_pwm(pin_num=12)
  

• reset_pin:

  Resets the given pin.

  Parameters:

  • pin_num (int): The GPIO pin.

  Example:

  GPIO_manager.reset_pin(pin_num=12)
  

• cleanup:

  Cleans up the GPIO pins by setting all output pins to low and clearing all interrupts.

  Example:

  GPIO_manager.cleanup()