Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!gatech!ukma!husc6!ogccse!verdix!sbq
From: sbq@verdix.com (Sam Quiring)
Newsgroups: comp.arch
Subject: Re: 8086 design goals
Message-ID: <362@verdix.verdix.com>
Date: 10 May 89 07:05:36 GMT
References: <912@aber-cs.UUCP> <3312@bd.sei.cmu.edu>
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Reply-To: sbq@verdix.com (Sam Quiring)
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Organization: Verdix Western Operations; Aloha, OR
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In article <3312@bd.sei.cmu.edu> firth@sei.cmu.edu (Robert Firth) writes:
>In article <912@aber-cs.UUCP> pcg@cs.aber.ac.uk (Piercarlo Grandi) writes:
>
>>Well, the problem with the Intel architecture is that it was designed for
>>Pascal, whose pointers can only point to heap allocated objects (and no
>>arithmetic on them is allowed).
>
>Leaving aside the question whether the Intel 8086 architecture was
>"designed" for anything, let alone Pascal ...

The Intel 8086 was definitely *not* designed with Pascal in mind (I did get
a good belly laugh out of that statement).  It was designed to provide an
upgrade path for 8080/8085 assembly language software (see note below), to
have 16-bit arithmetic (the 8080 had 8-bit arithmetic), and to be able to
address one megabyte of memory.  The 8085 gave Intel a lot of problems in
production, so they were very conservative with how much silicon the 8086
was permitted.  I believe it has about 29,000 transistor equivalents (the
486 has 1.2M!).  The 8086 was announced and available with PL/M-86 support
in June 1978.

Above all else, the 8086 was designed to make Intel a lot of money.  You may
not like the architecture, but I'd say it met all it's design goals.

Note: Intel provided an asm80 -> asm86 converter program, written by
John Crawford, architect of the 386/486.

Sam Quiring
Verdix Western Operations
uunet!vrdxhq!verdix!sbq

PS: I joined Intel in July of 1977 and worked on ASM86 (just the assembler,
not the assembly language!).