Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!think!bradley From: bradley@think.COM (Bradley Kuszmaul) Newsgroups: comp.unix.wizards,comp.arch Subject: Re: *Why* do modern machines mostly have 8-bit bytes? Message-ID: <6724@think.UUCP> Date: Wed, 22-Jul-87 09:57:45 EDT Article-I.D.: think.6724 Posted: Wed Jul 22 09:57:45 1987 Date-Received: Fri, 24-Jul-87 04:15:41 EDT References: <142700010@tiger.UUCP> <2792@phri.UUCP> <8315@utzoo.UUCP> <2807@phri.UUCP> Sender: news@think.UUCP Reply-To: bradley@godot.think.com.UUCP (Bradley Kuszmaul) Organization: Thinking Machines Corporation, Cambridge, MA Lines: 18 Xref: mnetor comp.unix.wizards:3355 comp.arch:1658 In article <2807@phri.UUCP> roy@phri.UUCP (Roy Smith) writes: >... > Anybody for a bit-aligned processor with variable word size (in the >same way the pdp-10 had variable byte size)? You could do "ADD X, Y, I" >where X and Y are the operands and I is the number of bits of precision >wanted. I should really mark that with a :-), but I'm partly serious (a >small part). The Connection Machine has 64K processors and the instruction set does include exactly the ADD instruction you describe. (Except of course, it is a "vector add"). It can be argued that many applications gain a lot by not having to do 32 bit operations when the data only has 6 bits of precision (e.g. vision algorithms). -Brad Bradley C. Kuszmaul, Thinking Machines Corporation, Cambridge, MA bradley@think.com bradley@think.uucp (i.e. seismo!think!bradley)