差别

这里会显示出您选择的修订版和当前版本之间的差别。

--- mp_ws2812 [2021/09/30 12:37]
gongyusu
+++ mp_ws2812 [2021/10/16 15:29] (当前版本)
gongyusu [1. 连线图]
@@ 行 1: / 行 1: @@
 ## WS2812B RGB三色灯的控制
-[[https://makersportal.com/blog/ws2812-ring-light-with-raspberry-pi-pico|ws2812的控制]]
+  - [[https://makersportal.com/blog/ws2812-ring-light-with-raspberry-pi-pico|ws2812的控制]]
-[[https://github.com/makerportal/rpi-pico-ws2812|Github上的资源整理]]
+  - [[https://github.com/makerportal/rpi-pico-ws2812|Github上的资源整理]]
+{{ :ws2812timing.png |}}
-- Wiring Diagram -
+### WS2812B教程内容
+[[mp_ws2812b|]]
+### 1. 连线图
 The wiring diagram between the Raspberry Pi Pico and a 16-pixel RGB LED ring light is shown below:
@@ 行 17: / 行 22: @@
 -	GND	GND
 Most of the GPIO pins can be used to control the WS2812 LED array, thus, the specification of GPIO13 for controlling the light is arbitrary. Be sure to change the pin in the codes as well, if using another pin for wiring.
+{{::WS2812_Pin.png|}}
+### 2. ws2812的使用示例
-- MicroPython State Machine -
 The 16-Pixel RGB LED ring light array will be controlled using the scheme outlined in the Raspberry Pi Pico MicroPython getting started document, where we can get started with the tutorial entitled “Using PIO to drive a set of NeoPixel Ring (WS2812 LEDs).” The tutorial contains a script that will be used to create a state machine on the RPi Pico. The state machine will be used to control the LEDs on the ring light using a single pin on the Pico (GPIO13 in the wiring above). The full MicroPython example script can also be found at the Raspberry Pi Pico’s NeoPixel Ring repository.
-The code to start the state machine on the Pico's GPIO pin #13 is given below:
+The code to start the state machine on the Pico's GPIO pin #20 is given below:
+<code python>
+# Example using PIO to drive a set of WS2812 LEDs.
 import array, time
 from machine import Pin
 import rp2
-#
-############################################
-# RP2040 PIO and Pin Configurations
-############################################
-#
-# WS2812 LED Ring Configuration
-led_count = 16 # number of LEDs in ring light
-PIN_NUM = 13 # pin connected to ring light
-brightness = 0.5 # 0.1 = darker, 1.0 = brightest
-@rp2.asm_pio(sideset_init=rp2.PIO.OUT_LOW, out_shiftdir=rp2.PIO.SHIFT_LEFT,
+# Configure the number of WS2812 LEDs.
-             autopull=True, pull_thresh=24) # PIO configuration
+NUM_LEDS = 16
+PIN_NUM = 6
+brightness = 0.2
-# define WS2812 parameters
+@rp2.asm_pio(sideset_init=rp2.PIO.OUT_LOW, out_shiftdir=rp2.PIO.SHIFT_LEFT, autopull=True, pull_thresh=24)
 def ws2812():
     T1 = 2
@@ 行 55: / 行 55: @@
-# Create the StateMachine with the ws2812 program, outputting on pre-defined pin
+# Create the StateMachine with the ws2812 program, outputting on pin
-# at the 8MHz frequency
+sm = rp2.StateMachine(0, ws2812, freq=8_000_000, sideset_base=Pin(PIN_NUM))
-state_mach = rp2.StateMachine(0, ws2812, freq=8_000_000, sideset_base=Pin(PIN_NUM))
+# Start the StateMachine, it will wait for data on its FIFO.
+sm.active(1)
+# Display a pattern on the LEDs via an array of LED RGB values.
+ar = array.array("I", [0 for _ in range(NUM_LEDS)])
+##########################################################################
+def pixels_show():
+    dimmer_ar = array.array("I", [0 for _ in range(NUM_LEDS)])
+    for i,c in enumerate(ar):
+        r = int(((c >> 8) & 0xFF) * brightness)
+        g = int(((c >> 16) & 0xFF) * brightness)
+        b = int((c & 0xFF) * brightness)
+        dimmer_ar[i] = (g<<16) + (r<<8) + b
+    sm.put(dimmer_ar, 8)
+    time.sleep_ms(10)
+def pixels_set(i, color):
+    ar[i] = (color[1]<<16) + (color[0]<<8) + color[2]
+def pixels_fill(color):
+    for i in range(len(ar)):
+        pixels_set(i, color)
+def color_chase(color, wait):
+    for i in range(NUM_LEDS):
+        pixels_set(i, color)
+        time.sleep(wait)
+        pixels_show()
+    time.sleep(0.2)
+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 (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(wait):
+    for j in range(255):
+        for i in range(NUM_LEDS):
+            rc_index = (i * 256 // NUM_LEDS) + j
+            pixels_set(i, wheel(rc_index & 255))
+        pixels_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)
-# Activate the state machine
+print("fills")
-state_mach.active(1)
+for color in COLORS:
-The snippet of code given above will be used for each algorithm used to test the 16-pixel WS2812 LED ring light.
+    pixels_fill(color)
+    pixels_show()
+    time.sleep(0.2)
+print("chases")
+for color in COLORS:
+    color_chase(color, 0.01)
+print("rainbow")
+rainbow_cycle(0)
+</code>