Re: Detecting an 80486

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#1901

From: Sidney Markowitz
Date: Thu, 16 Aug 1990 18:16

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In article <3827@altos86.Altos.COM> rcollins@altos86.UUCP (Robert Collins) writes:
>
>In article <1990Aug14.025550.17669@esegue.segue.boston.ma.us>
>johnl@esegue.segue.boston.ma.us (John R. Levine) writes:
>>  The Intel 486 Programmer's manual has sample code to tell the difference
>>  among the 8086, 286, 386, and 486 without any trapping at all.
>
>The code being referenced is on page 22-12 of the Intel "i486 Microprocessor
>Programmer's Reference Manual" (PRM) PN 240486.  The code on this page does
>NOT detect the difference between '386 and '486.

The code to detect the difference between the '386 and '486 is hidden away
on page 3-42. It uses bit 18 of EFLAGS. The code that I posted that is derived
from that worked in real mode and in virtual 8086 mode (for the latter, at
least it worked under QEMM 5.0, which I assume means it was in VM 8086 mode).
I don't know why the code you tried didn't work in real mode. You might compare
the two to find out why. I have not tried mine out in protected mode.

-- sidney markowitz <sidney@saturn.ucsc.edu>

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From: sidney@saturn.ucsc.edu (Sidney Markowitz )
Newsgroups: comp.os.msdos.programmer
Subject: Re: Detecting an 80486
Message-ID: <6077@darkstar.ucsc.edu>
Date: 16 Aug 90 18:16:45 GMT
References: <1990Aug14.025550.17669@esegue.segue.boston.ma.us> <OTTO.90Aug15022916@tukki.jyu.fi> <3827@altos86.Altos.COM>
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