Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!dg!rec
From: rec@dg.dg.com (Robert Cousins)
Newsgroups: comp.arch
Subject: Re: IBM PC prehistory
Message-ID: <250@dg.dg.com>
Date: 4 Jan 90 13:58:56 GMT
References: <1546@aber-cs.UUCP> <33896@mips.mips.COM> <21559@uflorida.cis.ufl.EDU> <1989Dec30.235854.14254@world.std.com> <10131@microsoft.UUCP>
Reply-To: uunet!dg!rec (Robert Cousins)
Organization: Data General, Westboro, MA.
Lines: 53

In article <10131@microsoft.UUCP> gordonl@microsoft.UUCP (Gordon LETWIN) writes:
>In article <1989Dec30.235854.14254@world.std.com>, bzs@world.std.com (Barry Shein) writes:
>> >> I think that IBM choose Intel for largely business reasons...
>> >At the time, IBM owned a large percentage of Intel stock (> 20%). Because
>> >of this, It is unlikely they would have gone to another chip maker.
>This is wrong... IBM bought a piece of Intel long after they chose the
>8088 for the IBM Pc.  I seem to recall that they've since sold their
>stake, as well.
>Although I'm not an authority on the subject, I'm pretty sure that the
>reason IBM used the 8088 is because of Intels clever marketing policy.
>They designed the 8086 first, and then produced an 8 bit version, the 8088.
>The 8088 is actually slightly more complex than the 8086 because of the
>add on circuitry to "narrow" the bus interface, but they sold it much
>cheaper in the theory that once the low price gets people "tied in" to the
>instruction set then they'll upgrade to the much higher profit margin 8086.
>I think that IBM used the 8088 because it was very much cheaper than
>the other 16 bit chips at the time (IBM originally was thinking of something
>like an 8085 - an 8 bit machine) and it also reduced system cost with
>it's 8 bit bus.
>	gordon letwin
>	microsoft

Actually, the options available at the time were:

	Z80 (IBM marketed an S100 Z80 CP/M machine in Europe for 4 months)
	808[05] (No real advantage over the Z80 and some real disadvantages)
	808[68] (Could address more memory, had no real installed base)
	68000   (Not really very solid yet as I recall)
	Z8000   (Not shipping in quantity for larger address space)
	TI 9900 (Not really an option)
	6809	(Fast, ready, but not that much better than the Z80)

One mistake which will go down in history is that Motorola chose
to pitch the 6809 over the 68k to IBM.  This whole slice of
computer history which will probably be viewed in the future as
a turning point which altered the entire industry forever would
have been changed had any one of a list of things been different:

	Motorola pitched the 68K instead of the 6809.
	The Z800 had been ready on schedule.
	The Z8000 had been a real product at that time.
	The NSC 16000 been ready 2 years earlier.
	The 808[68] had been buggier.
	Compupro had not chosen to support both the 8088 and 8085 on a 
		single system.

This is obviously my personal optionion (pronounced blithering).

Robert Cousins.
Dept. Mgr, Workstation Dev't.
Data General Corp.

Speaking for myself alone.