Create ws2812b.py

ws2812b.py

@@ -0,0 +1,32 @@
+import array, time
+from machine import Pin
+import rp2
+
+@rp2.asm_pio(sideset_init=rp2.PIO.OUT_LOW, out_shiftdir=rp2.PIO.SHIFT_LEFT, autopull=True, pull_thresh=24)
+def ws2812():
+    T1 = 2
+    T2 = 5
+    T3 = 3
+    wrap_target()
+    label("bitloop")
+    out(x, 1)               .side(0)    [T3 - 1]
+    jmp(not_x, "do_zero")   .side(1)    [T1 - 1]
+    jmp("bitloop")          .side(1)    [T2 - 1]
+    label("do_zero")
+    nop()                   .side(0)    [T2 - 1]
+    wrap()
+    
+class ws2812b:
+    def __init__(self, num_leds, state_machine, pin):
+        self.pixels = array.array("I", [0 for _ in range(num_leds)])
+        self.sm = rp2.StateMachine(state_machine, ws2812, freq=8000000, sideset_base=Pin(pin))
+        self.sm.active(1)
+        self.num_leds = num_leds
+
+    def set_pixel(self, pixel_num, red, green, blue):
+        self.pixels[pixel_num] = blue | red << 8 | green << 16
+        
+    def show(self):
+        for i in range(self.num_leds):
+            self.sm.put(self.pixels[i],8)
+