# Example using PIO to drive a set of WS2812 LEDs. import array, time from machine import Pin import rp2 from time import sleep import dma # Configure the number of WS2812 LEDs. NUM_LEDS = 256 PIN_NUM = 0 brightness = 0.2 @rp2.asm_pio(sideset_init=rp2.PIO.OUT_LOW, out_shiftdir=rp2.PIO.SHIFT_RIGHT, 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, pin_num, brightness, state_machine): # Create the StateMachine with the ws2812 program, outputting on pin self.sm = rp2.StateMachine(state_machine, ws2812, freq=8_000_000, sideset_base=Pin(pin_num)) # Start the StateMachine, it will wait for data on its FIFO. self.sm.active(1) # Display a pattern on the LEDs via an array of LED RGB values. self.ar = array.array("I", [0 for _ in range(num_leds)]) self.num_leds = num_leds self.brightness = brightness self.pio_dma = dma.PIO_DMA_Transfer(state_machine+4, state_machine, 32, num_leds) def show(self): #self.sm.put(self.ar) self.pio_dma.start_transfer(self.ar) def set(self, i, color): self.ar[i] = int((color[1]<<16)*self.brightness) + int((color[0]<<8)*self.brightness) + int(color[2]*self.brightness) def fill(self, color): for i in range(len(self.ar)): self.set(i, color) def wait(self): return self.pio_dma.busy() def color_chase(self, color, wait): for i in range(self.num_leds): self.set(i, color) time.sleep(wait) self.show() time.sleep(0.2) def wheel(self, 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 (0, 0, 0) if pos < 85: return (255 - pos * 3, pos * 3, 0) if pos < 170: pos -= 85 return (0, 255 - pos * 3, pos * 3) pos -= 170 return (pos * 3, 0, 255 - pos * 3) def rainbow_cycle(self, wait): for j in range(255): for i in range(self.num_leds): rc_index = (i * 256 // self.num_leds) + j self.set(i, self.wheel(rc_index & 255)) self.show() time.sleep(wait) BLACK = (0, 0, 0) RED = (255, 0, 0) YELLOW = (255, 150, 0) GREEN = (0, 255, 0) CYAN = (0, 255, 255) BLUE = (0, 0, 255) PURPLE = (180, 0, 255) WHITE = (255, 255, 255) COLORS = (BLACK, RED, YELLOW, GREEN, CYAN, BLUE, PURPLE, WHITE) if __name__ == "__main__": ws0 = WS2812B(256, 1, 1, 1) ws1 = WS2812B(256, 2, 1, 5) ws2 = WS2812B(256, 3, 1, 6) while True: for color in ws0.COLORS: ws0.fill(color) ws0.show() ws1.fill(color) ws1.show() ws2.fill(color) ws2.show() time.sleep(1)