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[color=rgba(0, 0, 0, 0.87)]等成功用串口或者ADB连接开发板之后，就可以通过终端命令对开发板进行控制了。 [color=rgba(0, 0, 0, 0.87)]接下来会介绍Tina Linux系统封装几个模块，您可以通过命令启动这几个模块的demo，操控终端几个模块的软硬件。首先是我们大学单片机课程中的必修课：点灯 [color=rgba(0, 0, 0, 0.87)]R329支持LEDC，LEDC全称 “Light Emitting Diode Controller”，是借助Linux LED标准子系统实现的LED控制模块，可以对LED灯进行点亮、亮度调节、闪烁、阵列控制等操作。LEDC模块在无屏幕智能音箱上用得很多，比如在等待配对、唤醒、音乐播放等场景，LED灯会以不同的效果表示当前状态。 [color=rgba(0, 0, 0, 0.87)]内置固件已经编译好了LEDC模块，可以直接对LED节点进行控制从而点亮LED灯。 进入LED灯路径[color=rgba(0, 0, 0, 0.87)]首先，我们可以进入LED节点的位置查看一个LED灯三个颜色的节点（R G B）： code" style="box-sizing: inherit; -webkit-tap-highlight-color: transparent; font-size: inherit; font-family: inherit; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial; border-width: 0px; border-style: initial; border-color: initial; position: absolute; top: 0.5em; right: 0.5em; z-index: 1; width: 1.5em; height: 1.5em; border-radius: 0.1rem; outline: none; outline-offset: 0.1rem; cursor: pointer; transition: color 0.25s ease 0s;">root@TinaLinux:/# cd /sys/class/leds/root@TinaLinux:/sys/class/leds# lssunxi_led0b sunxi_led0g sunxi_led0r[color=rgba(0, 0, 0, 0.87)] [color=var(--md-typeset-a-color)] [color=rgba(0, 0, 0, 0.87)]三个节点分别代三个颜色，我们可以进入一个颜色节点，比如红色（R）： code" style="box-sizing: inherit; -webkit-tap-highlight-color: transparent; font-size: inherit; font-family: inherit; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial; border-width: 0px; border-style: initial; border-color: initial; position: absolute; top: 0.5em; right: 0.5em; z-index: 1; width: 1.5em; height: 1.5em; border-radius: 0.1rem; outline: none; outline-offset: 0.1rem; cursor: pointer; transition: color 0.25s ease 0s;">root@TinaLinux:/sys/class/leds# cd sunxi_led0r/root@TinaLinux:/sys/devices/platform/soc/ledc/leds/sunxi_led0r# lsbrightness device subsystemdelay_off max_brightness triggerdelay_on power uevent[color=rgba(0, 0, 0, 0.87)] [color=var(--md-typeset-a-color)] [color=rgba(0, 0, 0, 0.87)]可以看到LEDC已经做好了很多LEDC的基本操作，包括亮度调节、闪烁、延时等。 点亮一个灯[color=rgba(0, 0, 0, 0.87)]如果我们要点亮其中一个颜色，可以把亮度值写到 brightness 里，亮度值最高为255： code" style="box-sizing: inherit; -webkit-tap-highlight-color: transparent; font-size: inherit; font-family: inherit; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial; border-width: 0px; border-style: initial; border-color: initial; position: absolute; top: 0.5em; right: 0.5em; z-index: 1; width: 1.5em; height: 1.5em; border-radius: 0.1rem; outline: none; outline-offset: 0.1rem; cursor: pointer; transition: color 0.25s ease 0s;">root@TinaLinux:/sys/devices/platform/soc/ledc/leds/sunxi_led0r# echo 255 > brightness[color=rgba(0, 0, 0, 0.87)]此时LED灯会被点亮 [color=rgba(0, 0, 0, 0.87)] [color=var(--md-typeset-a-color)] [color=rgba(0, 0, 0, 0.87)]如果要调节亮度值的话，只需调节写到 brightness 的值即可，亮度值范围为0~255，0代表熄灭，255代表最亮： code" style="box-sizing: inherit; -webkit-tap-highlight-color: transparent; font-size: inherit; font-family: inherit; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial; border-width: 0px; border-style: initial; border-color: initial; position: absolute; top: 0.5em; right: 0.5em; z-index: 1; width: 1.5em; height: 1.5em; border-radius: 0.1rem; outline: none; outline-offset: 0.1rem; cursor: pointer; transition: color 0.25s ease 0s;">root@TinaLinux:/sys/devices/platform/soc/ledc/leds/sunxi_led0r# echo 255 > brightnessroot@TinaLinux:/sys/devices/platform/soc/ledc/leds/sunxi_led0r# echo 100 > brightnessroot@TinaLinux:/sys/devices/platform/soc/ledc/leds/sunxi_led0r# echo 10 > brightnessroot@TinaLinux:/sys/devices/platform/soc/ledc/leds/sunxi_led0r# echo 0 > brightness[color=rgba(0, 0, 0, 0.87)] [color=var(--md-typeset-a-color)] [color=rgba(0, 0, 0, 0.87)] [color=var(--md-typeset-a-color)] [color=rgba(0, 0, 0, 0.87)]如果要点亮其它颜色的灯 ，只需要参照红灯，将亮度值写到绿灯和蓝灯的 brightness 里即可： code" style="box-sizing: inherit; -webkit-tap-highlight-color: transparent; font-size: inherit; font-family: inherit; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial; border-width: 0px; border-style: initial; border-color: initial; position: absolute; top: 0.5em; right: 0.5em; z-index: 1; width: 1.5em; height: 1.5em; border-radius: 0.1rem; outline: none; outline-offset: 0.1rem; cursor: pointer; transition: color 0.25s ease 0s;">root@TinaLinux:/sys/class/leds# echo 255 > sunxi_led0g/brightnessroot@TinaLinux:/sys/class/leds# echo 0 > sunxi_led0g/brightnessroot@TinaLinux:/sys/class/leds# echo 255 > sunxi_led0b/brightnessroot@TinaLinux:/sys/class/leds# echo 0 > sunxi_led0b/brightness[color=rgba(0, 0, 0, 0.87)] [color=var(--md-typeset-a-color)] [color=rgba(0, 0, 0, 0.87)] [color=var(--md-typeset-a-color)] [color=rgba(0, 0, 0, 0.87)]如果要实现LED灯闪烁的效果，把 timer 写到 trigger 即可： code" style="box-sizing: inherit; -webkit-tap-highlight-color: transparent; font-size: inherit; font-family: inherit; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial; border-width: 0px; border-style: initial; border-color: initial; position: absolute; top: 0.5em; right: 0.5em; z-index: 1; width: 1.5em; height: 1.5em; border-radius: 0.1rem; outline: none; outline-offset: 0.1rem; cursor: pointer; transition: color 0.25s ease 0s;">root@TinaLinux:/sys/class/leds# echo timer > sunxi_led0r/trigger[color=rgba(0, 0, 0, 0.87)]如果你看到灯亮了，那么恭喜你，它将照亮你嵌入式开发学习的路。 [color=rgba(0, 0, 0, 0.87)]LED灯阵列操作、模块配置、源码结构、内外部接口等进阶操作请见开发文档《Tina Linux LED开发指南》：[color=var(--md-typeset-a-color)]《Tina Linux LED开发指南》下载 [color=rgba(0, 0, 0, 0.87)]同时，还可以使用三个PWM接口对LED的三色灯进行控制，但需要占用较多的引脚和资源。
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