Development, round II - test-drb@ccmp.vtda.org

29 Jan 1998

If I remember correctly, IBM released the XT 286 when the second generation
PC/AT (with a faster clock - wasn't it 8 MHz?) came out. It was my
impression then that the XT286 was an XT case with the older original AT
motherboard inside.

-----Original Message-----
From: Mike Allison &lt;mallison(a)konnections.com&gt;
To: Discussion re-collecting of classic computers
&lt;classiccmp(a)u.washington.edu&gt;
Date: Thursday, January 29, 1998 10:04 PM
Subject: Re: Development, round II

...
 Tony:

I just seem to remember _something_ about the XT286 that made me avoid
it for true 286 stuff.  Maybe it was the memory.  Most after market AT
boards had room for a meg or two.  Maybe it was the 640...

-Mike

Tony Duell wrote:

  I've not got the XT-286 techref to hand, so I
can't look at the
 schematics. But I seem to remember that it's _very_ similar to the PC/AT
 - it's a lot closer to that machine than to the XT. There are 2 DMA
 controllers, 2 interrupt controllers, the 8042 keyboard controller (so it
 takes an AT keyboard), etc. My thoughts when I looked at the schematics
 were that it was a repackaged AT. Of course they could have missed out
 the extra reset logic, but I doubt it.

 It does use a non-standard motherboard, though. The memory is a little
 odd - 128K in DIPs (4 off 64K*4, 2 off 64K*1 for the parrity) and 2 256K
 SIMMs for a total of 640K.

 I guess....

 -Mike 
 -tony 