🚀 go-pugleaf

>Can someone please tell me what the patents on Microchannel are?
>In fact, if you've got a PS/2, I'd like to know what all of the patent
>numbers are.  They should be listed on a label somewhere on the outside
>of the machine, probably in the back.

>Also, in a recent interview with Jones of Chips and Technologies, he said
>any potential cloner of the 386 processor would have to deal with a few
>Intel patents related to protected mode.  Can someone tell me what the
>patent numbers for the patents on the 386 are?

As far as I know, none of the PS/2 patents have been issued.  All of IBM's
talk about the need for clone vendors to license the Micro Channel technology
was based on patent _applications_.  Given the typical delay in granting
patents, it is possible that some have now been issued, but it is also possible
that they are still all pending.

IBM does have a wide variety of general computer patents, as well as a number
of specific patents on the PC and AT designs.

As for cloning the 386, I believe that the primary patent of concern is
#4,442,484, "Microprocessor memory management and protection mechanism",
filed 10/14/80 and granted 4/10/84.  This patent describes the memory
management structure of the 286, which is also embodied in the 386.  There
may be some 386-specific patents as well, but I haven't heard anything about
them.  There are also two patents on the 8086/88 that may apply:

4,363,091  Extended address, single and multiple bit microprocessor
4,449,184  same title, but different content

We've put together a reprint of these three patents, which we sell for $20.
We also have a collection of 17 PC and AT patents for $40, and the famous
(and massive) "Christiansen" patent for $50.

(You can get all of these more cheaply by going directly to the US patent
office, but it can take months.  We provide these reprints mostly as a
service to our subscribers; it costs us a significant fraction of our prices
to copy, bind, and mail them.)

Michael Slater, Microprocessor Report    mslater@cup.portal.com
550 California Ave., Suite 320, Palo Alto, CA 94306
415/494-2677   fax: 415/494-3718