9-2.c

本书是单片机系列教材

/*9-2.c*/
#include<dos.h>
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);
}
}