单片机C51定时器实验扩展用开关控制加减方向源程序

ID:847253 · 发表于 2020-11-24 16:13

#include "reg51.h"
data unsigned char y _at_ 0x40;
unsigned char i=100;
void main()
{
  TMOD=0x01;
TH0=0xee;
TL0=0x00;
y=0xff;
P1=0x00;
EA=1;
ET0=1;
TR0=1;
while(1);
{;}

}

void timer0() interrupt 1
{
  TH0=0xee;
TL0=0x00;
i--;
if(i<=0)
{
if((P3&0x80)==0x00)  //判断P3.7口按钮按下
{
   --y;
                  P1=y;
   i=100;
}
else
               {
++y;
                              P1=y;
                              i=100;
}
}
}