PWM波控制直流电机

#include"at89x51.h"

int count0=0,count1=0,count2=0,fg1,fg2,fg3,k,l; sbit add=P1^4;

sbit dec=P1^5;

sbit PWM1=P3^6;

sbit PWM2=P3^7;

void delay(unsigned int tt)

{

while(tt--);

}

void high()

{

if(!add) fg1=1;

if(add &&fg1)

{

fg1=0;

count0=count0+5;

if(count0>=100)

count0=100;

}

}

void low()

{

if(!dec) fg2=1;

if(dec && fg2)

{

fg2=0;

count0-=5;

if(count0<=0)

count0=0;

}

void main()

{

EA=1;

TH0=(65536-1000)/256; TL0=(65536-1000)%256; TR0=1; ET0=1;

for(;;)

{

PWM1=0;

high();

low();

}

}

void fx() interrupt 1

{

TH0=(65536-1000)/256; TL0=(65536-1000)%256; count1++;

if(count1

{

PWM2=1;

}

else PWM2=0;

if(count1>=100)

{

count1=0;

}

}