add LED-cycling to simpletest

Author: Brennen Bearnes

examples/tlc5947_simpletest.py

@@ -1,13 +1,13 @@
 # Simple demo of controlling the TLC5947 12-bit 24-channel PWM controller.
 # Will update channel values to different PWM duty cycles.
 # Author: Tony DiCola
+
 import board
 import busio
 import digitalio
 
 import adafruit_tlc5947
 
-
 # Define pins connected to the TLC5947
 SCK = board.SCK
 MOSI = board.MOSI
@@ -30,19 +30,36 @@
 # it is used in your code.  Change the duty_cycle property to a 16-bit value
 # (note this is NOT the 12-bit value supported by the chip natively) and the
 # PWM channel will be updated.
-pwm0 = tlc5947.create_pwm_out(0)
 
-# Set the channel 0 PWM to 50% (32767, or half of the max 65535):
-pwm0.duty_cycle = 32767
+# With an RGB LED hooked up to pins 0, 1, and 2, cycle the red, green, and
+# blue pins up and down:
+
+red = tlc5947.create_pwm_out(0)
+green = tlc5947.create_pwm_out(1)
+blue = tlc5947.create_pwm_out(2)
+
+step = 10
+start_pwm = 0
+end_pwm = 32767 # 50% (32767, or half of the maximum 65535):
+
+for pin in (red, green, blue):
+    # Brighten:
+    for pwm in range(start_pwm, end_pwm, step):
+        pin.duty_cycle = pwm
+
+    # Dim:
+    for pwm in range(end_pwm, start_pwm, 0 - step):
+        pin.duty_cycle = pwm
+
 # Note if auto_write was disabled you need to call write on the parent to
 # make sure the value is written (this is not common, if disabling auto_write
 # you probably want to use the direct 12-bit raw access instead shown below).
-#tlc5947.write()
+# tlc5947.write()
 
 # The other way to read and write channels is directly with each channel 12-bit
 # value and an item accessor syntax.  Index into the TLC5947 with the channel
 # number (0-23) and get or set its 12-bit value (0-4095).
 # For example set channel 1 to 50% duty cycle.
-tlc5947[1] = 2048
+# tlc5947[1] = 2048
 # Again be sure to call write if you disabled auto_write.
 #tlc5947.write()