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改這樣就可以了
/*************************************************
*實(shí)驗(yàn)名:定時器實(shí)驗(yàn)
*實(shí)驗(yàn)效果:第一個led燈以1000ms一次的精確頻率閃爍
*************************************************/
#include<reg52.h>
sbit led = P1^0;
int i = 1;
void timer1_init()
{
TMOD = 0x10; //定時器1選擇工作方式1
TH1 = 0x4C; //設(shè)置初始值,定時50ms
TL1 = 0x00;
EA = 1; //打開總中斷
ET1 = 1; //打開定時器1中斷
TR1 = 1; //啟動定時器1
}
void main()
{
led = 1;
timer1_init();
while(1)
{
if(i>=20)
{
i=0;
led = ~led;
}
}
}
void timer1() interrupt 3
{
TH1 = 0x4C; //設(shè)置初始值,定時50ms
TL1 = 0x00;
i++;
} |
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