INT 48 - TI Professional PCIBM PC - SPEAKER DEVICE - SOUND SPEAKER
	AH = 00h
	AL = number of 25ms ticks sound should last
Return: nothing
Desc:	sound the speaker at the current frequency setting (see AH=02h) for
	  the indicated duration
Notes:	this function returns immediately; the sound is terminated by the
	  timer interrupt handler
	if a new sound is requested while one is already in progress, the
	  previous sound is terminated immediately and the new sound takes
	  its place
SeeAlso: AH=01h,AH=02h,AH=03h,AH=04h,AH=06h,AH=08h,AH=0Ah,AH=0Bh
SeeAlso: INT 40"TI Professional",INT 49/AH=01h"TI"
SeeAlso: INT 4A/AH=00h"TI",INT 4C"TI Professional",INT 4D/AH=00h