外部中断

中断

下降沿触发

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char
#define segN  4

uchar code segD[] = {
                                        0x3f,0x06,0x5b,0x4f,0x66,
                                        0x6d,0x7d,0x07,0x7f,0x6f,
                                        0x00,0xf3};
uchar code segW[] = {
                                        0xf7,0xfb,0xfd,0xfe
                                        };
uchar num[segN];
                                        
uint a=807;

void delay(uint timer)
{       
    uchar j = 124;
    while(timer--)
    {
        while(j--);
    }
}
                                                                        
void display(uint k)
{
    uchar i;
    for(i=0; i<segN; i++)
    {
        int result=1;
        num[segN-i-1]=k/result%10;
        result*=10;
        k/=10;
        P2 = segW[i];
        P0 = segD[num[segN-i-1]];
        delay(1);
    }   
}

void exit_init()
{
    EA=1;
    IT0=1;//下降沿触发
    IT1=1;
    EX0=1;
    EX1=1;
}

void main()
{       
        exit_init();
        while(1)
        {
            display(a);
        }
}

void int0_inter() interrupt 0
{
        a++;
}

void int1_inter() interrupt 2
{
    a=0;
}

低电平触发

void exit_init()
{
EA=1;
IT0=0;//低电平触发
IT1=1;
EX0=1;
EX1=1;
}

定时器

工作方式0

工作方式0

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char
   
sbit led = P2^0;
uchar num;

void int0_inter() interrupt 0
{
       num=0;
       TL0=0x18;
       TH0=0X63;
       TR0=1;
}

void int1_inter() interrupt 2
{
       TR0=0;
}

void timer0_inter() interrupt 1
{
       num++;
       TL0=0x18;
       TH0=0x63;
}

void exit_init()
{
       IT0=1;
       IT1=1;
       EX0=1;
       EX1=1;
       
       TMOD=0;
       TL0=0x18;
       TH0=0X63;
       ET0=1;
       EA=1;
}

void main()
{
       exit_init();
       num=0;
       P2=0xff;
       
       while(1)
       {
               if(num>=200)
               {
                       num=0;
                       led=~led;
               }
       }
}

工作方式1

工作方式1

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char
    
sbit out_pin = P2^0;

void timer0_inter() interrupt 1
{
        out_pin = ~ out_pin;
        TL0=0X78;
        TH0=0XEC;
}

void exit_init()
{
        TMOD=1;
        TL0=0x78;
        TH0=0XEC;
        ET0=1;
        EA=1;
        TR0=1;
}

void main()
{
        exit_init();
        P2=0xff;
        
        while(1)
        {
            ;
        }
}

示波器

工作方式2

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char
    
sbit out_pin = P2^0;

void timer0_inter() interrupt 1
{
        out_pin = ~ out_pin;
}

void exit_init()
{
        TMOD=2;
        TL0=0x06;
        TH0=0X06;
        ET0=1;
        EA=1;
        TR0=1;
}

void main()
{
        exit_init();
        P2=0xff;
        
        while(1)
        {
            ;
        }
}

工作方式2

工作方式3

工作方式3

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char
    
sbit out_A = P2^0;
sbit out_B = P2^1;

void timerTL0_inter() interrupt 1
{
        out_A = ~ out_A;
        TL0 =0;
}

void timerTH0_inter() interrupt 3
{
        out_B = ~ out_B;
        TH0=128;
}

void exit_init()
{
        TMOD=3;
        TL0=0;
        TH0=128;
        EA=1;
        ET0=1;
        ET1=1;
        TR0=1;
        TR1=1;
}

void main()
{
        exit_init();
        P2=0xff;
        
        while(1)
        {
            ;
        }
}

计数器

计数功能是对外部脉冲进行计数，捕捉输入脉冲的下降沿，从T0（P3.4）和T1（P3.5）两个引脚输入。

计数器

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char
#define segN  4

uchar code segD[] = {
                                        0x3f,0x06,0x5b,0x4f,0x66,
                                        0x6d,0x7d,0x07,0x7f,0x6f,
                                        0x00,0xf3};

void delay(uint timer)
{       
    uchar j = 124;
    while(timer--)
    {
        while(j--);
    }
}
                                        
void display(uint k)
{
    uchar a = k%10;
    uchar b = k/10%10;
    
    P2 = 0xfe;
    P0 = segD[b];
    delay(5);
    
    P2 = 0xfd;
    P0 = segD[a];
    delay(5);
}

                                        
void int0_inter() interrupt 0
{
        TL1 =0;
}

void timer_inter() interrupt 3
{
        TL1=0;
}

void exit_init()
{
    
        IT0=1;
        EX0=1;
        TMOD=0x60;
        TL1=0;
        TH1=0;
        EA=1;
        ET1=1;
        TR1=1;
}

void main()
{   
        uchar num;
        exit_init();
        P2=0xff;
        
        while(1)
        {
            num = TL1;
            display(num);
        }
}