《C语言程序设计实训》第九章

				/*9-2.c*/
				#include
				main()    /* music */
				{
				   int note,length;
				length=10;
				do {
						note=getchar( );
						play(note,length);
				}while (note!='q');
				}
				play(int note, int l)
				  {
					 int tone;
						l=l+1000/note;
				   for( ;l ;l--) {
					   tone=note;
				outportb(0x61,2);  /* turn on speaken */
				outportb(0x61,0);  /* turn off speaker */
				for( ;tone;--tone);
				}
				}