Merge pull request #70 from geekguy-wy/constructor_brighness_parameter

Constructor brightness parameter

adafruit_ht16k33/ht16k33.py

@@ -47,8 +47,9 @@ class HT16K33:
     :param int address: The I2C addess of the HT16K33.
     :param bool auto_write: True if the display should immediately change when
         set. If False, `show` must be called explicitly.
+    :param float brightness: 0.0 - 1.0 default brightness level.
     """
-    def __init__(self, i2c, address=0x70, auto_write=True):
+    def __init__(self, i2c, address=0x70, auto_write=True, brightness=1.0):
         self.i2c_device = i2c_device.I2CDevice(i2c, address)
         self._temp = bytearray(1)
         self._buffer = bytearray(17)
@@ -58,7 +59,7 @@ def __init__(self, i2c, address=0x70, auto_write=True):
         self._blink_rate = None
         self._brightness = None
         self.blink_rate = 0
-        self.brightness = 15
+        self.brightness = brightness
 
     def _write_cmd(self, byte):
         self._temp[0] = byte
@@ -81,16 +82,18 @@ def blink_rate(self, rate=None):
 
     @property
     def brightness(self):
-        """The brightness. Range 0-15."""
+        """The brightness. Range 0.0-1.0"""
         return self._brightness
 
     @brightness.setter
     def brightness(self, brightness):
-        if not 0 <= brightness <= 15:
-            raise ValueError('Brightness must be an integer in the range: 0-15')
-        brightness = brightness & 0x0F
+        if not 0.0 <= brightness <= 1.0:
+            raise ValueError('Brightness must be a decimal number in the range: 0.0-1.0')
+
         self._brightness = brightness
-        self._write_cmd(_HT16K33_CMD_BRIGHTNESS | brightness)
+        xbright = round(15 * brightness)
+        xbright = xbright & 0x0F
+        self._write_cmd(_HT16K33_CMD_BRIGHTNESS | xbright)
 
     @property
     def auto_write(self):

examples/ht16k33_animation_demo.py

@@ -38,7 +38,7 @@
 DEFAULT_CYCLES = 5
 
 #   Brightness of the display (0 to 15)
-DEFAULT_DISPLAY_BRIGHTNESS = 2
+DEFAULT_DISPLAY_BRIGHTNESS = 0.3
 
 #   Initialize the I2C bus
 i2c = busio.I2C(board.SCL, board.SDA)