Update README.rst

Added Simple Test Example

Author: bwshockley

README.rst

@@ -60,7 +60,92 @@ To install in a virtual environment in your current project:
 Usage Example
 =============
 
-.. todo:: Add a quick, simple example. It and other examples should live in the examples folder and be included in docs/examples.rst.
+.. code-block:: shell
+
+        # Simple test for an RGB encoder.  This tests incrementing, decrementing, button presses, RGB value changes, Fade setup, etc.
+
+        # Author: Ben Shockley
+
+        # imports
+        import i2cEncoderLibV21
+        import busio
+        import board
+        import time
+        import digitalio
+        import struct
+
+        # Setup the Inturrpt Pin from the encoder.  
+        INT = digitalio.DigitalInOut(board.A3)
+        INT.direction = digitalio.Direction.INPUT
+        INT.pull = digitalio.Pull.UP
+
+        # Initialize the device.
+        i2c = busio.I2C(board.SCL, board.SDA)
+        encoder = i2cEncoderLibV21.i2cEncoderLibV21(i2c, 0x21)
+
+        def EncoderChange():
+            encoder.writeRGBCode(0x00FF00)
+            valBytes = struct.unpack('>i', encoder.readCounter32())
+            print ('Changed: {}'.format(valBytes[0]))
+
+        def EncoderPush():
+            encoder.writeRGBCode(0x0000FF)
+            print ('Encoder Pushed!')
+
+        def EncoderRelease():
+            encoder.writeRGBCode(0x00FFFF)
+            print ('Encoder Released!')
+
+        def EncoderDoublePush():
+            encoder.writeRGBCode(0xFF00FF)
+            print ('Encoder Double Push!')
+
+        def EncoderMax():
+            encoder.writeRGBCode(0xFF0000)
+            print ('Encoder max!')
+
+        def EncoderMin():
+            encoder.writeRGBCode(0xFF0000)
+            print ('Encoder min!')
+
+        def EncoderFade():
+            encoder.writeRGBCode(0x000000)
+
+        def Encoder_INT(self):
+            encoder.updateStatus()
+
+        # Start by resetting the encoder. Reset takes 400us , so let us give it time to settle.
+        encoder.reset()
+        time.sleep(.1)
+
+        # When the board was initialized, the default config was loaded.  Here we can override that config if we want.
+        encconfig = (i2cEncoderLibV21.INT_DATA | i2cEncoderLibV21.WRAP_DISABLE | i2cEncoderLibV21.DIRE_RIGHT | i2cEncoderLibV21.IPUP_ENABLE | i2cEncoderLibV21.RMOD_X1 | i2cEncoderLibV21.RGB_ENCODER)
+        encoder.begin(encconfig)
+
+        # Setup other varibles
+        encoder.writeCounter(0)
+        encoder.writeMax(10)
+        encoder.writeMin(-10)
+        encoder.writeStep(1)
+        encoder.writeAntiBouncePeriod(25)
+        encoder.writeDoublePushPeriod(50)
+        encoder.writeFadeRGB(2)
+
+        # Declare callbacks
+        encoder.onChange = EncoderChange
+        encoder.onButtonRelease = EncoderRelease
+        encoder.onButtonPush = EncoderPush
+        encoder.onButtonDoublePush = EncoderDoublePush
+        encoder.onMax = EncoderMax
+        encoder.onMin = EncoderMin
+        encoder.onFadeProcess = EncoderFade
+
+        # Autoconfigure the interrupt register according to the callbacks declared.
+        encoder.autoconfigInterrupt()
+
+        while True:
+            if not INT.value:       #If INT pin goes LOW - we know the encoder status changed.
+                Encoder_INT(encoder)
 
 Contributing
 ============