《C语言程序设计实训》源代码

				/*8-1.c*/
				#include 
				#include 
				#include 
				#include 
				#include 
				#define INTR 0x1c
				void interrupt ( *oldhandler) ();
				int fre[]={523,659,587,659,587,494,587,523,440,440,440,330,392,440,494,494,330,415,494,523,523,523};
				
				void interrupt handler(){
				unsigned i;
				static int flag;
				static int k=0;
				union{
					long divisor;
					unsigned char c[2];
					}music;
				unsigned char port;
				flag++;
				if (flag>=4){
				flag=0;
				music.divisor=1190000/fre[k];
				outportb(67,182);
				outportb(66,music.c[0]);
				outportb(66,music.c[1]);
				port=inportb(97);
				outport(97,port|3);
				k++;
				if(k>=22) k=1;
				}
				oldhandler();
				}
				
				int main(void)
				{
					int gdriver=DETECT,gmode,errorcode;
					int midx,midy,i;
					oldhandler=getvect(INTR);
					setvect(INTR,handler);
					initgraph(&gdriver,&gmode,"c:\\bc\\bin");
					errorcode=graphresult();
					if(errorcode!=grOk)
						{
						printf("graphic error:%s\n",grapherrormsg(errorcode));
						printf("press any key to halt");
						getch();
						exit(1);
						}
						midx=getmaxx()/2;
						midy=getmaxy()/2;
						for(i=SOLID_FILL;i						 {
						 setfillstyle(i,getmaxcolor());
						 bar(midx-50,midy-50,midx+50,midy+50);
						 delay(2000);
						 }
						 getch();
						 closegraph();
						 setvect(INTR,oldhandler);
						 nosound();
						 return(0);
						 }