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diff --git a/Adafruit_Python_CharLCD/examples/char_lcd_rgb_pwm.py b/Adafruit_Python_CharLCD/examples/char_lcd_rgb_pwm.py
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+#!/usr/bin/python
+# Example using an RGB character LCD with PWM control of the backlight.
+import math
+import time
+
+import Adafruit_CharLCD as LCD
+
+
+def hsv_to_rgb(hsv):
+    """Converts a tuple of hue, saturation, value to a tuple of red, green blue.
+    Hue should be an angle from 0.0 to 359.0.  Saturation and value should be a
+    value from 0.0 to 1.0, where saturation controls the intensity of the hue and
+    value controls the brightness.
+    """
+    # Algorithm adapted from http://www.cs.rit.edu/~ncs/color/t_convert.html
+    h, s, v = hsv
+    if s == 0:
+        return (v, v, v)
+    h /= 60.0
+    i = math.floor(h)
+    f = h-i
+    p = v*(1.0-s)
+    q = v*(1.0-s*f)
+    t = v*(1.0-s*(1.0-f))
+    if i == 0:
+        return (v, t, p)
+    elif i == 1:
+        return (q, v, p)
+    elif i == 2:
+        return (p, v, t)
+    elif i == 3:
+        return (p, q, v)
+    elif i == 4:
+        return (t, p, v)
+    else:
+        return (v, p, q)
+
+# Raspberry Pi configuration:
+lcd_rs = 27  # Change this to pin 21 on older revision Raspberry Pi's
+lcd_en = 22
+lcd_d4 = 25
+lcd_d5 = 24
+lcd_d6 = 23
+lcd_d7 = 18
+lcd_red   = 4
+lcd_green = 17
+lcd_blue  = 7  # Pin 7 is CE1
+
+# BeagleBone Black configuration:
+# lcd_rs = 'P8_8'
+# lcd_en = 'P8_10'
+# lcd_d4 = 'P8_18'
+# lcd_d5 = 'P8_16'
+# lcd_d6 = 'P8_14'
+# lcd_d7 = 'P8_12'
+# lcd_red   = 'P9_16'
+# lcd_green = 'P9_14'
+# lcd_blue  = 'P8_13'
+
+# Define LCD column and row size for 16x2 LCD.
+lcd_columns = 16
+lcd_rows    = 2
+
+# Alternatively specify a 20x4 LCD.
+# lcd_columns = 20
+# lcd_rows    = 4
+
+# Initialize the LCD using the pins
+lcd = LCD.Adafruit_RGBCharLCD(lcd_rs, lcd_en, lcd_d4, lcd_d5, lcd_d6, lcd_d7,
+                              lcd_columns, lcd_rows, lcd_red, lcd_green, lcd_blue,
+                              enable_pwm=True)
+
+# Show some basic colors.
+lcd.set_color(1.0, 0.0, 0.0)
+lcd.clear()
+lcd.message('RED')
+time.sleep(3.0)
+
+lcd.set_color(0.0, 1.0, 0.0)
+lcd.clear()
+lcd.message('GREEN')
+time.sleep(3.0)
+
+lcd.set_color(0.0, 0.0, 1.0)
+lcd.clear()
+lcd.message('BLUE')
+time.sleep(3.0)
+
+lcd.set_color(1.0, 1.0, 0.0)
+lcd.clear()
+lcd.message('YELLOW')
+time.sleep(3.0)
+
+lcd.set_color(0.0, 1.0, 1.0)
+lcd.clear()
+lcd.message('CYAN')
+time.sleep(3.0)
+
+lcd.set_color(1.0, 0.0, 1.0)
+lcd.clear()
+lcd.message('MAGENTA')
+time.sleep(3.0)
+
+lcd.set_color(1.0, 1.0, 1.0)
+lcd.clear()
+lcd.message('WHITE')
+time.sleep(3.0)
+
+# Use HSV color space so the hue can be adjusted to see a nice gradient of colors.
+# Hue ranges from 0.0 to 359.0, saturation from 0.0 to 1.0, and value from 0.0 to 1.0.
+hue = 0.0
+saturation = 1.0
+value = 1.0
+
+# Loop through all RGB colors.
+lcd.clear()
+print('Press Ctrl-C to quit.')
+while True:
+    # Convert HSV to RGB colors.
+    red, green, blue = hsv_to_rgb((hue, saturation, value))
+    # Set backlight color.
+    lcd.set_color(red, green, blue)
+    # Print message with RGB values to display.
+    lcd.set_cursor(0, 0)
+    lcd.message('RED  GREEN  BLUE\n{0:0.2f}  {1:0.2f}  {2:0.2f}'.format(red, green, blue))
+    # Increment hue (wrapping around at 360 degrees).
+    hue += 1.0
+    if hue > 359.0:
+        hue = 0.0