1 files changed, 83 insertions, 0 deletions
diff --git a/orangepwm.py b/orangepwm.py
new file mode 100644
index 0000000..c874fcb
--- /dev/null
+++ b/orangepwm.py
@@ -0,0 +1,83 @@
+from pyA20.gpio import gpio as GPIO
+import threading
+import time
+
+
+class OrangePwm(threading.Thread):
+    def __init__(self, frequency, gpioPin, gpioScheme=0):
+        """
+        Init the OrangePwm instance. Expected parameters are :
+        - frequency : the frequency in Hz for the PWM pattern. A correct value may be 100.
+        - gpioPin : the gpio.port which will act as PWM ouput
+        - gpioScheme : saved for compatibility with PiZyPWM code
+        """
+        super().__init__()
+
+        self.baseTime = 1.0 / frequency
+        self.maxCycle = 100.0
+        self.sliceTime = self.baseTime / self.maxCycle
+        self.gpioPin = gpioPin
+        self.terminated = False
+        self.toTerminate = False
+        # GPIO.setmode(gpioScheme)
+
+    def start(self, dutyCycle):
+        """
+        Start PWM output. Expected parameter is :
+        - dutyCycle : percentage of a single pattern to set HIGH output on the GPIO pin
+
+        Example : with a frequency of 1 Hz, and a duty cycle set to 25, GPIO pin will
+        stay HIGH for 1*(25/100) seconds on HIGH output, and 1*(75/100) seconds on LOW output.
+        """
+        self.dutyCycle = dutyCycle
+        GPIO.setcfg(self.gpioPin, GPIO.OUTPUT)
+        self.thread = threading.Thread(None, self.run, None, (), {})
+        self.thread.start()
+
+    def run(self):
+        """
+        Run the PWM pattern into a background thread. This function should not be called outside of this class.
+        """
+        while self.toTerminate == False:
+            if self.dutyCycle > 0:
+                GPIO.output(self.gpioPin, GPIO.HIGH)
+                time.sleep(self.dutyCycle * self.sliceTime)
+
+            if self.dutyCycle < self.maxCycle:
+                GPIO.output(self.gpioPin, GPIO.LOW)
+                time.sleep((self.maxCycle - self.dutyCycle) * self.sliceTime)
+
+        self.terminated = True
+
+    def changeDutyCycle(self, dutyCycle):
+        """
+        Change the duration of HIGH output of the pattern. Expected parameter is :
+        - dutyCycle : percentage of a single pattern to set HIGH output on the GPIO pin
+
+        Example : with a frequency of 1 Hz, and a duty cycle set to 25, GPIO pin will
+        stay HIGH for 1*(25/100) seconds on HIGH output, and 1*(75/100) seconds on LOW output.
+        """
+        self.dutyCycle = dutyCycle
+
+    def changeFrequency(self, frequency):
+        """
+        Change the frequency of the PWM pattern. Expected parameter is :
+        - frequency : the frequency in Hz for the PWM pattern. A correct value may be 100.
+
+        Example : with a frequency of 1 Hz, and a duty cycle set to 25, GPIO pin will
+        stay HIGH for 1*(25/100) seconds on HIGH output, and 1*(75/100) seconds on LOW output.
+        """
+        self.baseTime = 1.0 / frequency
+        self.sliceTime = self.baseTime / self.maxCycle
+
+    def stop(self):
+        """
+        Stops PWM output.
+        """
+        self.toTerminate = True
+        while self.terminated == False:
+            # Just wait
+            time.sleep(0.01)
+
+        GPIO.output(self.gpioPin, GPIO.LOW)
+        GPIO.setcfg(self.gpioPin, GPIO.INPUT)