1、c有2组LED：D3和D4，每组LED都有蓝，绿，红三种颜色。
LED位置如下图所示：
2、JN-mini5728 LED位置与操作方式
3、点亮LED
root@am57xx-evm:~# echo 1 > /sys/class/leds/status_usr0/brightness
root@am57xx-evm:~# echo 1 > /sys/class/leds/status_usr1/brightness
root@am57xx-evm:~# echo 1 > /sys/class/leds/status_usr2/brightness
root@am57xx-evm:~# echo 1 > /sys/class/leds/status_usr3/brightness
root@am57xx-evm:~# echo 1 > /sys/class/leds/status_usr4/brightness
root@am57xx-evm:~# echo 1 > /sys/class/leds/status_usr5/brightness
4、关闭LED
root@am57xx-evm:~# echo 0 > /sys/class/leds/status_usr0/brightness
root@am57xx-evm:~# echo 0 > /sys/class/leds/status_usr1/brightness
root@am57xx-evm:~# echo 0 > /sys/class/leds/status_usr2/brightness
root@am57xx-evm:~# echo 0 > /sys/class/leds/status_usr3/brightness
root@am57xx-evm:~# echo 0 > /sys/class/leds/status_usr4/brightness
root@am57xx-evm:~# echo 0 > /sys/class/leds/status_usr5/brightness
