fengmingqi.zip_蜂鸣器

#include"reg52.h" #define led P2 typedef unsigned char u8; typedef unsigned int u16; sbit beep=P1^5; void delay(u16 i) { while(i--); } void main() { u16 i,j; while(1) { for(i=110;i>0;i-=1) { beep=1; delay(i); beep=0; delay(20); } delay(1000); for(j=0;j<110;j+=1) { beep=1; delay(j); beep=0; delay(20); } } }