C语言 计时器的实现（利用系统55ms中断计时）

//利用系统55ms中断，显示时间//作者：nuaazdh//时间：2011年11月30日#include <stdio.h>#include <dos.h>#include <bios.h>#include <ctype.h>#include <conio.h>#include <graphics.h>#include <math.h>unsigned long count=0;//每55ms中断，count+1int hour=0,minute=0,second=0,millisecond=0;char time[10];struct time t;void interrupt get();void interrupt (*old)();//中断程序void interrupt get(){count+=1;}//获取时间void Clock(){millisecond=(count*55)%1000;second=(count*55/1000)%60;minute=(count*55/60000%60)%60;hour=(count*55/3600000%24)%24;}//显示时间void PrintClock(){clrscr();printf("\n\n\n\n");printf("\t\tThe beginning time:  ");printf("%02d:%02d:%02d\n\n",t.ti_hour,t.ti_min,t.ti_sec);printf("\t\tThe current time is: \n\n");printf("\t\tInterrupt counts:   \n\n");printf("\t\tPress esc to exit!");}//更新显示void UpdateClock(){gotoxy(38,7);//定位屏幕指定位置printf("%02d:%02d:%02d\n\n",hour,minute,second);//更新显示gotoxy(37,9);//定位中断数目位置printf("%06d",count);}//获取用户输入，检测Esc退出void End(){long key;while(bioskey(1)!=0){key=bioskey(0);key=key&0x00FF;if(key==27){setvect(0x1C,old);exit(0);}}}void main(){old=getvect(0x1C);//得到中断向量setvect(0x1C,get);//设置中断向量gettime(&t);//获取时间PrintClock();//显示时间while(1){Clock();UpdateClock();//更新显示End();}}

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