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From: Terry Lambert <terry@lambert.org>
Message-Id: <199604070029.RAA28711@phaeton.artisoft.com>
Subject: Re: BROKEN_KBD still doesnt work
To: dennis@etinc.com (dennis)
Date: Sat, 6 Apr 1996 17:29:02 -0700 (MST)
Cc: hackers@FreeBSD.ORG
In-Reply-To: <199604061641.LAA13367@etinc.com> from "dennis" at Apr 6, 96 11:41:37 am
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> Running 2.1R, I have a MB that give me a "keyboard reset fails" message
> when I attempt to reboot. Configuring BROKEN_KEYBOARD_RESET
> gets rid of the message, but the machine still doesn't reboot.
> 
> What else can I try?

The first reset attempt is the keyboard reset.  This can fail because
of gate A20 wrap being assumed by the BIOS, or the segment being
assumed by the BIOS so it won't work from protected mode, etc..

The second reset attempt is to cause a triple fault.

The BROKEN_KEYBOARD_RESET flag says "don't do the keyboard reset",
which causes yu to go right to the triple fault.

If your motherboard hardware causes a soft instead of a hard reset on
a triple fault, technically it's broken.

If both the keyboard and the triple fault are broken, welcome to
Big Red Switchville, population 15% of all 386 and above computers.


Potential fixes:

1)	Detect if you have an EISA bus; if you do, use the EISA
	hardware reset instead of the keyboard or triple fault.

2)	Detect if you have an PCI bus; if you do, use the PCI
	hardware reset instead of the keyboard or triple fault.

3)	Get a fixed BIOS that doesn't depend on gate A20 or
	segment selectors.

4)	Get a fixed motherboard that hardresets when it is uspposed
	to.  This will fix the 3c509 PnP card recognition-on-cold-boot
	problem at the same time.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.