Merge pull request #21 from mrmcwethy/examples

Added examples folder and example .py

Author: ladyada

examples/strip.py

@@ -0,0 +1,61 @@
+# CircuitPython demo - NeoPixel
+
+import time
+import board
+import neopixel
+
+
+# On CircuitPlayground Express -> Board.NEOPIXEL
+# Otherwise choose an open pin connected to the Data In of the NeoPixel strip,
+# such as board.D1
+pixpin = board.NEOPIXEL
+
+# The number of pixels in the strip
+numpix = 10
+
+# number of colors in each pixel, =3 for RGB, =4 for RGB plus white
+BPP = 3
+
+strip = neopixel.NeoPixel(pixpin, numpix, bpp=BPP, brightness=0.3, auto_write=False)
+
+def format_tuple(r, g, b):
+    if BPP == 3:
+        return (r, g, b)
+    return (r, g, b, 0)
+
+def wheel(pos):
+    # Input a value 0 to 255 to get a color value.
+    # The colours are a transition r - g - b - back to r.
+    if (pos < 0) or (pos > 255):
+        return format_tuple(0, 0, 0)
+    if pos < 85:
+        return format_tuple(int(pos * 3), int(255 - (pos*3)), 0)
+    elif pos < 170:
+        pos -= 85
+        return format_tuple(int(255 - pos*3), 0, int(pos*3))
+    #else:
+    pos -= 170
+    return format_tuple(0, int(pos*3), int(255 - pos*3))
+
+def rainbow_cycle(wait):
+    for j in range(255):
+        for i in range(strip.n):
+            idx = int((i * 256 / len(strip)) + j)
+            strip[i] = wheel(idx & 255)
+        strip.show()
+        time.sleep(wait)
+
+while True:
+    strip.fill(format_tuple(255, 0, 0))
+    strip.show()
+    time.sleep(1)
+
+    strip.fill(format_tuple(0, 255, 0))
+    strip.show()
+    time.sleep(1)
+
+    strip.fill(format_tuple(0, 0, 255))
+    strip.show()
+    time.sleep(1)
+
+    rainbow_cycle(0.001)    # rainbowcycle with 1ms delay per step