智能车制作

标题: mc9s12xs128的外部中断例子 [打印本页]

作者: 转角over 时间: 2013-9-9 21:24
标题: mc9s12xs128的外部中断例子
mc9s12xs128的外部中断的例子

#include <hidef.h>    /* common defines and macros */
#include "derivative.h"    /* derivative-specific definitions */

#pragma CODE_SEG __NEAR_SEG NON_BANKED
void interrupt 24 PORTJ_ISR(void)
{
   PORTB_PB0=~PORTB_PB0;
   PIFJ_PIFJ0=1; //清除中断标志位
}
#pragma CODE_SEG __NEAR_SEG NON_BANKED

void interrupt 25 PORTH_ISR(void)
{
  PORTB_PB2=~PORTB_PB2;
  PIFH_PIFH7=1; //清除中断标志位
}

void SetBusCLK_32M(void)
{
   CLKSEL=0X00; // disengage PLL to system
   PLLCTL_PLLON=1; // turn on PLL
   SYNR =0x40 | 0x03;  // pllclock=2*osc*(1+SYNR)/(1+REFDV)=64MHz;
   REFDV=0xc0 | 0x01;
   POSTDIV=0x00;
   _asm(nop);       // BUS CLOCK=32M
   _asm(nop);
   while(!(CRGFLG_LOCK==1)); //when pll is steady ,then use it;
   CLKSEL_PLLSEL =1;       //engage PLL to system;
  }

void Dly_ms(int ms)
{
int ii,jj;
if (ms<1) ms=1;
for(ii=0;ii<ms;ii++)
//for(jj=0;jj<1335;jj++);  //16MHz--1ms
for(jj=0;jj<2770;jj++);  //32MHz--1ms
//for(jj=0;jj<4006;jj++);  //48MHz--1ms
//for(jj=0;jj<5341;jj++); //64MHz--1ms
}

static void Port_Init(void)
{

DDRB = 0xff; //LED  PTB0--7,
PORTB= 0xff; //LEDs on

DDRH = 0x00; // PORTH input
PTIH = 0X00; // KEY,PH0--5
PERH = 0xff; // PORTH pull up
PPSH = 0x00; // Port H Polarity Select Register-falling edge
PIEH = 0x80; // PORTH interrut disable,
               // PH7判断奇偶场换场信号

DDRJ = 0X00; // PJ0判断行同步脉冲到达
//PPSJ = 0x01; // Port J Polarity Select Register-rising EDGE
PPSJ = 0x00; // Port J Polarity Select Register-falling EDGE
PIEJ = 0X01; // VIDEO SYNC INTERRUPT DISABLED,BUT NOT IN MAIN()
PERJ = 0xff;
}

void main(void)
{ /* put your own code here */
byte i=0;
Port_Init();          // initial board
SetBusCLK_32M();
PORTB=0XFF;
EnableInterrupts;
for(;;)
{
   Dly_ms(500);
   PORTB_PB1=~PORTB_PB1;
} /* please make sure that you never leave this */

}

问一下，什么样的外部信号才能产生中断啊？？？？
跪求答案

补充内容 (2013-9-9 22:07):
具体一点，向H7口上输入一个下降沿脉冲，就会进入中断函数吗？？

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