嵌入式工程师的520表白

点灯，嵌入式工程师难以割舍的独有情怀。也只有他们才能这么大胆，用耀眼绿光在温馨霓虹中跳脱闪现，变幻中演绎与众不同的浪漫爱意。

520点灯表白，为爱发光——今晚就脱单！快来~

本教程示例采用合宙LuatOS-SoC系列Air105开发板、WS2812系列LED光源演示

1

LuatOS-SoC驱动WS2812的三种方式

WS2812是一款比较常用的外控集成LED光源，控制简单，应用领域极广——包括但不限于表白。

具有低电压驱动、环保节能、亮度高、散射角度大、一致性好、低功率及超长寿命等优点。

驱动WS2812需要满足如下条件，显然不是所有MCU都能支持的：

LuatOS-SoC三种驱动方式

合宙LuatOS-SoC在支持GPIO直驱的情况下，加入了PWM和SPI驱动的方法：

sensor.ws2812b_pwm(pin,data)

sensor.ws2812b_spi(pin,data)

下面看看这两个函数对硬件要求：

sensor.ws2812b_pwm(pin,data)：
800k的PWM输出频率

sensor.ws2812b_spi(pin,data)：
5Mbps的SPI输出速率

显然，这要求就很低了。三种驱动方式，总有一款适合你：

Air101/Air103系列：

推荐使用SPI驱动方式；

Air105系列：

推荐使用PWM驱动方式，也可使用SPI驱动方式；GPIO直驱也可以，但实际有点勉强。

2

520表白程序开发/demo下载

接下来，我们正式编写表白程序。

01

首先将我们要显示的内容，换算成GBR颜色数组：

local show_520 = {
{0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff},
{0x0000ff,0x00ff00,0x00ff00,0x0000ff,0x0000ff,0x00ff00,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff},
{0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff},
{0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x00ff00,0x0000ff,0x00ff00,0x0000ff,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff},
{0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x0000ff,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff},
{0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x00ff00,0x0000ff,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x00ff00,0x0000ff,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff},
{0x0000ff,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x00ff00,0x00ff00,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff},
{0x0000ff,0x0000ff,0x0000ff,0x00ff00,0x00ff00,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff,0x0000ff},

}local show_520_w = 24local show_520_h = 8

02之后，申请一个8*8的zbuff空间：

local ws2812_w = 8local ws2812_h = 8
local buff = zbuff.create({ws2812_w,ws2812_h,24},0x000000)

03然后，我们做一个简单的滚动显示函数就可以了：

local function ws2812_roll_show(show_data,data_w)
local m = 0
while 1 do
for j=0,ws2812_w-1 do
if j%2==0 then
for i=ws2812_w-1,0,-1 do
if m+ws2812_w-i>data_w then
buff:pixel(i,j,show_data[j+1][m+ws2812_w-i-data_w]) else
buff:pixel(i,j,show_data[j+1][m+ws2812_w-i]) end
end
else
for i=0,ws2812_w-1 do
if m+i+1>data_w then
buff:pixel(i,j,show_data[j+1][m+i+1-data_w]) else
buff:pixel(i,j,show_data[j+1][m+i+1]) end
end
end
end
m = m+1
if m==data_w then m=0 end
sensor.ws2812b_pwm(5,buff)--此处使用pwm方法驱动,当然也可以用gpio,spi方式,API详情查看wiki https://wiki.luatos.com/api/sensor.html
-- sensor.ws2812b_spi(0,buff)

sys.wait(300)
end
end

好，我们的点灯表白程序写好了。前面没看视频的同学，来看一下点灯效果吧：

每个闪耀的LED，都是满满爱意

你学会了吗？

快来试试看！

发挥你的点灯创意为爱发光吧