樹莓派---GPIO應用詳解

https://www.jianshu.com/p/f31b90cc756f

https://www.jianshu.com/p/e93e2fe3f66a

http://wiki.jikexueyuan.com/project/raspberry-pi/gpio.html

https://blog.csdn.net/xdw1985829/article/details/39580401