drivers/led/neopixel: Add brightness control.

micropython/drivers/led/neopixel/manifest.py

@@ -1,3 +1,3 @@
-metadata(description="WS2812/NeoPixel driver.", version="0.1.0")
+metadata(description="WS2812/NeoPixel driver.", version="0.2.0")
 
 module("neopixel.py", opt=3)

micropython/drivers/led/neopixel/neopixel.py

@@ -8,10 +8,11 @@ class NeoPixel:
     # G R B W
     ORDER = (1, 0, 2, 3)
 
-    def __init__(self, pin, n, bpp=3, timing=1):
+    def __init__(self, pin, n, bpp=3, timing=1, brightness=None):
         self.pin = pin
         self.n = n
         self.bpp = bpp
+        self.b = None if brightness is None else min(max(brightness, 0), 1)
         self.buf = bytearray(n * bpp)
         self.pin.init(pin.OUT)
         # Timing arg can either be 1 for 800kHz or 0 for 400kHz,
@@ -22,11 +23,17 @@ def __init__(self, pin, n, bpp=3, timing=1):
             else timing
         )
 
+    def _b(self, v):
+        if self.b is not None:
+            return tuple(round(c * self.b) for c in v)
+        return v
+
     def __len__(self):
         return self.n
 
     def __setitem__(self, i, v):
         offset = i * self.bpp
+        v = self._b(v)
         for i in range(self.bpp):
             self.buf[offset + self.ORDER[i]] = v[i]
 
@@ -35,6 +42,7 @@ def __getitem__(self, i):
         return tuple(self.buf[offset + self.ORDER[i]] for i in range(self.bpp))
 
     def fill(self, v):
+        v = self._b(v)
         b = self.buf
         l = len(self.buf)
         bpp = self.bpp
@@ -45,6 +53,13 @@ def fill(self, v):
                 b[j] = c
                 j += bpp
 
+    def brightness(self, b=None):
+        if b is None:
+            return self.b
+        self.b = min(max(b, 0), 1)
+        for i in range(self.n * self.bpp):
+            self.buf[i] = round(self.buf[i] * self.b)
+
     def write(self):
         # BITSTREAM_TYPE_HIGH_LOW = 0
         bitstream(self.pin, 0, self.timing, self.buf)

micropython/drivers/led/neopixel/neopixel_test.py

@@ -0,0 +1,29 @@
+import machine
+import neopixel
+
+
+def neopixel_test():
+    np = neopixel.NeoPixel(machine.Pin(1), 3)
+    print("Fill with a color.")
+    np.fill((255, 128, 64))
+    print("Verify the bytes to be written")
+    expected = bytearray([255, 128, 64, 255, 128, 64, 255, 128, 64])
+    actual = np.buf
+    passed = "passed" if expected == actual else "failed"
+    print(f"Initial fill: {passed}.")
+    print()
+
+    print("Change brightness of all pixels.")
+    np.brightness(0.5)
+    expected = bytearray([127, 64, 32, 127, 64, 32, 127, 64, 32])
+    actual = np.buf
+    passed = "passed" if expected == actual else "failed"
+    print(f"Brightness change: {passed}.")
+    print()
+
+    print("Get current brightness.")
+    expected = 0.5
+    actual = np.brightness()
+    passed = "passed" if expected == actual else "failed"
+    print(f"Brightness get: {passed}.")
+    print()