TakwayBoard/tools/orangepi_spi_ws2812.py

import time
import spidev
import wiringpi
 
# 0码 t0H 220ns~380ns
# （python 中GPIO口无法翻转这么快，python 可能执行一行代码需要800ns）
# ws2812 波特率如果设置为800kHZ, 1/0.8M=1.25us (0码或者1码所需要的时间)
 
# 使用SPI产生ws2812时序，产生1码和0码，则可以使用传输一个byte 来代表一个0码或者1码，如下：
# 1111 1000 0xF8  #1码 高电平时间长，低电平时间短
# 1100 0000 0xC0  #0码 高电平时间短，低电平时间长
# 则得出SPI 波特率应该设置为800K*8
 
sig_1 = 0xf8
sig_0 = 0xc0
 
 
def flatten_arrays(arrays):
    return [element for sublist in arrays for element in sublist]
 
 
class WS2812:
    def __init__(self, led_num=1):
        self.led_num = led_num
        self.ws2812_data = [[sig_0 for _ in range(24)] for _ in range(led_num)]
        spi = spidev.SpiDev()
 
        # 设置一下下拉，否则第一盏灯的时序可能不正确
        wiringpi.wiringPiSetup()
        wiringpi.pullUpDnControl(11, 1)
        spi.open(0, 0)
        spi.max_speed_hz = 6400000
        spi.mode = 0
 
        self.spi = spi
 
    def ws2812_send_data(self):
        default_tx = self.ws2812_data
        self.spi.xfer2(bytes(flatten_arrays(default_tx)))
 
    def ws2812_light_led(self, red, green, blue, pix_led):
        default_tx = self.ws2812_data
        color = green << 16 | red << 8 | blue
        for i in range(24):
            if color >> (24 - i - 1) & 1:
                default_tx[pix_led][i] = sig_1
            else:
                default_tx[pix_led][i] = sig_0
 
    def ws2812_light_one_led(self, red, green, blue, pix_led):
        self.ws2812_light_led(red, green, blue, pix_led)
        self.ws2812_send_data()
 
    def ws2812_light_all_led(self, red, green, blue):
        for i in range(self.led_num):
            self.ws2812_light_led(red, green, blue, i)
 
        self.ws2812_send_data()
 
    def ws2812_rainbow(self):
        colors = [[0xff, 0, 0], [0, 0xff, 0], [0, 0, 0xff]]
        for i in range(self.led_num):
            cur_color = colors[i % 3]
            self.ws2812_light_led(cur_color[0], cur_color[1], cur_color[2], i)
        self.ws2812_send_data()
 
    def ws2812_water_lamp(self, red, green, blue, interval_time):
        self.ws2812_shutoff_all()
 
        for i in range(self.led_num):
            self.ws2812_light_one_led(red, green, blue, i)
            time.sleep(interval_time)
 
        self.ws2812_shutoff_all()
 
    def ws2812_shutoff_led(self, n):
        self.ws2812_light_led(0, 0, 0, n)
        self.ws2812_send_data()
 
    def ws2812_shutoff_all(self):
        for i in range(self.led_num):
            self.ws2812_light_led(0, 0, 0, i)
 
        self.ws2812_send_data()
 
 
if __name__ == '__main__':
    ws2812 = WS2812(8)
 
    while True:
        ws2812.ws2812_light_all_led(0, 0, 0xff)
        time.sleep(0.5)
        ws2812.ws2812_light_all_led(0xff, 0, 0)
        time.sleep(0.5)
        ws2812.ws2812_light_all_led(0, 0xff, 0)
        time.sleep(0.5)
        # ws2812.ws2812_water_lamp(0xff, 0, 0, 0.2)
        # time.sleep(0.5)