#include #include"XT2.h" #define uint unsigned int #define uchar unsigned char void initsys()//XT2时钟初始化 { uchar k; P5SEL |= BIT2+BIT3; // P5.2和P5.3是 XT2 脚,24MHz晶振 UCSCTL6 &= ~(XT2OFF);//开启XT2晶振 UCSCTL3 |= SELREF_。