-# SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries
-#
-# SPDX-License-Identifier: MIT
-
-""" PWMOut Class for lgpio lg library tx_pwm library """
-
-import lgpio
-from adafruit_blinka.microcontroller.bcm283x.pin import CHIP
-
-
-class PWMError(IOError):
- """Base class for PWM errors."""
-
-
-class PWMOut:
- """Pulse Width Modulation Output Class"""
-
- def __init__(self, pin, *, frequency=500, duty_cycle=0, variable_frequency=False):
- if variable_frequency:
- print("Variable Frequency is not supported, ignoring...")
- self._pin = pin
- result = lgpio.gpio_claim_output(CHIP, self._pin.id, lFlags=lgpio.SET_PULL_NONE)
- if result < 0:
- raise RuntimeError(lgpio.error_text(result))
- self._enabled = False
- self._deinited = False
- self._period = 0
- # set frequency
- self._frequency = frequency
- # set duty
- self.duty_cycle = duty_cycle
- self.enabled = True
-
- def __del__(self):
- self.deinit()
-
- def __enter__(self):
- return self
-
- def __exit__(self, _exc_type, _exc_val, _exc_tb):
- self.deinit()
-
- def deinit(self):
- """Deinit the PWM."""
- if not self._deinited:
- if self.enabled:
- self._enabled = False # turn off the pwm
- self._deinited = True
-
- def _is_deinited(self):
- """raise Value error if the object has been de-inited"""
- if self._deinited:
- raise ValueError(
- "Object has been deinitialize and can no longer "
- "be used. Create a new object."
- )
-
- @property
- def period(self):
- """Get or set the PWM's output period in seconds.
-
- Raises:
- PWMError: if an I/O or OS error occurs.
- TypeError: if value type is not int or float.
-
- :type: int, float
- """
- return 1.0 / self.frequency
-
- @period.setter
- def period(self, period):
- if not isinstance(period, (int, float)):
- raise TypeError("Invalid period type, should be int or float.")
-
- self.frequency = 1.0 / period
-
- @property
- def duty_cycle(self):
- """Get or set the PWM's output duty cycle which is the fraction of
- each pulse which is high. 16-bit
-
- Raises:
- PWMError: if an I/O or OS error occurs.
- TypeError: if value type is not int or float.
- ValueError: if value is out of bounds of 0.0 to 1.0.
-
- :type: int, float
- """
- return int(self._duty_cycle * 65535)
-
- @duty_cycle.setter
- def duty_cycle(self, duty_cycle):
- if not isinstance(duty_cycle, (int, float)):
- raise TypeError("Invalid duty cycle type, should be int or float.")
-
- if not 0 <= duty_cycle <= 65535:
- raise ValueError("Invalid duty cycle value, should be between 0 and 65535")
-
- # convert from 16-bit
- duty_cycle /= 65535.0
-
- self._duty_cycle = duty_cycle
- if self._enabled:
- self.enabled = True # turn on with new values
-
- @property
- def frequency(self):
- """Get or set the PWM's output frequency in Hertz.
-
- Raises:
- PWMError: if an I/O or OS error occurs.
- TypeError: if value type is not int or float.
-
- :type: int, float
- """
-
- return self._frequency
-
- @frequency.setter
- def frequency(self, frequency):
- if not isinstance(frequency, (int, float)):
- raise TypeError("Invalid frequency type, should be int or float.")
-
- self._frequency = frequency
- if self.enabled:
- self.enabled = True # turn on with new values
-
- @property
- def enabled(self):
- """Get or set the PWM's output enabled state.
-
- Raises:
- PWMError: if an I/O or OS error occurs.
- TypeError: if value type is not bool.
-
- :type: bool
- """
- return self._enabled
-
- @enabled.setter
- def enabled(self, value):
- if not isinstance(value, bool):
- raise TypeError("Invalid enabled type, should be bool.")
-
- frequency = self._frequency if value else 0
- duty_cycle = round(self._duty_cycle * 100)
- self._enabled = value
- result = lgpio.tx_pwm(CHIP, self._pin.id, frequency, duty_cycle)
- if result < 0:
- raise RuntimeError(lgpio.error_text(result))
- return result
-
- # String representation
- def __str__(self):
- return (
- f"pin {self._pin} (freq={self.frequency:f} Hz, duty_cycle="
- f"{self.duty_cycle}({round(self.duty_cycle / 655.35)}%)"
- )