Scroll Lock status & LED ?

Article View: comp.os.msdos.programmer

Article #2749

Back to comp.os.msdos.programmer Previous Next

#2749

From: Bob Davis
Date: Mon, 22 Oct 1990 19:17

20 lines
1596 bytes

	On my AT clone, when I zero the weight-16 bit in the
Keyboard Status byte at memory location 0040:0017, I also turn
off the LED Scroll Lock indicator. 
	Is this always true, or do some 
BIOSes require you also to twiddle things at OUT port 60h in order 
to turn the LED off? Some stuff I read seems to say so. I was
surprised when zero-ing the Status bit also did the LED on my AT.
	If I leave
the software only manipulating the Keyboard Status byte Scroll Lock
bit, then when I run it on different machines, is the Scroll Lock
LED indicator likely not to toggle in sync with the status bit?
	Thanks.

______________________________________________________________________________
Bob Davis, UofALA'66   \\ INTERNET : sonny@trantor.harris-atd.com  |  _   _  |
Harris Corporation, ESS \\    UUCP : ...!uunet!x102a!trantor!sonny |_| |_| | |
Advanced Technology Dept.\\ AETHER : K4VNO          |==============|_/\/\/\|_|
PO Box 37, MS 3A/1912     \\ VOICE : (407) 727-5886 | I SPEAK ONLY | |_| |_| |
Melbourne, FL 32902        \\  FAX : (407) 729-2537 | FOR MYSELF.  |_________|

Technical Details

Message-ID: <4624@trantor.harris-atd.com>

Path:

arc1-ca.pugleaf.net!utzoo!attcan!uunet!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!trantor.harris-atd.com!charybdis!sonny

Show Full Headers

Complete Article Headers

Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!trantor.harris-atd.com!charybdis!sonny
From: sonny@charybdis.harris-atd.com (Bob Davis)
Newsgroups: comp.os.msdos.programmer
Subject: Scroll Lock status & LED ?
Message-ID: <4624@trantor.harris-atd.com>
Date: 22 Oct 90 19:17:15 GMT
Sender: news@trantor.harris-atd.com
Reply-To: sonny@trantor.harris-atd.com (Bob Davis)
Distribution: na
Organization: Advanced Technology Dept., Harris ESS, Melbourne, FL
Lines: 20