]> Repositories - Adafruit_Blinka-hackapet.git/blobdiff - src/adafruit_blinka/microcontroller/generic_linux/lgpio_pwmout.py
Restructure and move pins to generic linux
[Adafruit_Blinka-hackapet.git] / src / adafruit_blinka / microcontroller / generic_linux / lgpio_pwmout.py
diff --git a/src/adafruit_blinka/microcontroller/generic_linux/lgpio_pwmout.py b/src/adafruit_blinka/microcontroller/generic_linux/lgpio_pwmout.py
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+# 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.generic_linux.lgpio_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)}%)"
+        )