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From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: comp.lang.c,comp.arch
Subject: Re: Was the 360 badly-designed?  (was Re: Compatibility with EBCDIC)
Message-ID: <8474@utzoo.UUCP>
Date: Mon, 24-Aug-87 15:40:17 EDT
Article-I.D.: utzoo.8474
Posted: Mon Aug 24 15:40:17 1987
Date-Received: Mon, 24-Aug-87 15:40:17 EDT
References: <855@tjalk.cs.vu.nl> <2683@hoptoad.uucp> <916@haddock.ISC.COM>
Organization: U of Toronto Zoology
Lines: 17

> 2. Small segments: 1 megabyte is not big enough?
>                    And the architecture transparently handles the transition
>                    from one segment to another...

I believe what was being referred to was not the way the MMU does segments,
but the 12-bit addressing offset, which effectively gives you 4096-byte
segments.  The management of the base registers needed to address things
within said segments is *not* transparent by a damn long sight.  Pointer
arithmetic, at least, uses a uniform address space, but ordinary addressing
doesn't.

> 4. BTW {:-)}, this message came from an Amdahl 5890-300 ...

Amdahl builds fine implementations of a truly scummy architecture.
-- 
Apollo was the doorway to the stars. |  Henry Spencer @ U of Toronto Zoology
Next time, we should open it.        | {allegra,ihnp4,decvax,utai}!utzoo!henry