[net.micro.pc] Speedup using INT 27H

jec (11/15/82)

	There is one program that I know of that uses the INT 27H
and actually works (although it defines another interrupt for some
reason I can't figure out).  Have you looked at SPEEDUP.COM?  I think
it was originally published in PC Magazine in either issue 3 or 4.
	I received another letter from someone else that had gotten
INT 27H to work for a screen printer (that spooled to the printer), but
he's had trouble with disk time-outs, but I suspect that was due
to the clock interrupt being foobared.
	The code for SPEEDUP.COM is thus:

			MOV	DX,12H
			MOV	AX,251E
			INT	21H		;CREATE INT 1E AT DS:12H
			MOV	DI,DX		;DI = 12H
			MOV	SI,DLOCH	;MOVE DATA INTO THE
			MOV	CX,0BH		; RESERVED PORTION OF
			REPZ			; THE PROGRAM SEGMENT
			MOVB			; PREFIX BLOCK.
			XOR	AX,AX
			INT	13H		;RESET DISK
			MOV	DX,DI		;SET LOWMEM AT END
			INT	27H		; OF THIS PROGRAM
		DLOC:	DB	DF,02,25,02,08
			DB	2A,FF,50,F6,00
			DB	04


	This is a nifty little program even aside from showing how to
use INT 27H.  If you have DOS 1.0 this will speed up your disk access
time by almost 100%.  All you have to do is run it.  

	Now, anyone out there with a working spooler?


			Mike (...devax!pur-ee!iuvax!isrnix!jec)