https://blog.youkuaiyun.com/longintchar/article/details/79439466
http://www.voidcn.com/article/p-bgnsvssb-sa.html
关于PIC(programmable interrupt controller)看上面的链接
https://blog.youkuaiyun.com/longintchar/article/details/79439466
http://www.voidcn.com/article/p-bgnsvssb-sa.html
关于PIC(programmable interrupt controller)看上面的链接