资料介绍
PIT代码#include /* common defines and macros */
#include /* derivative information */
#pragma LINK_INFO DERIVATIVE "mc9s12xs128"
//==================================================
//定时中断函数
//定时中断 0 实现 500MS 定时
//author:yangtze
//time:2009/5/2
//==================================================
#define PITTIME 5000//设定为 50MS 定时
unsigned int vTmpPIT=0;
void pllclk(void)//24MHz ,外部时钟为 16MHz
{
CLKSEL=0X00;
PLLCTL=0xe1;
SYNR=2;//PLLCL K =2*OSCCLK*(SYNR + 1)/(REFDV + 1)
REFDV=1;
PLLCTL=0X60;
asm NOP;
asm NOP;
asm NOP;
while((CRGFLG&0X08)==0);//时钟校正同步
CLKSEL=0X80;
}
void initIOBoutput(void)//IO 口初始化,B 口为输出
{
DDRB=0XFF;
PORTB=0XFF;
}
void initPIT(void)//