Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!rutgers!im4u!milano!baxter From: baxter@milano.UUCP Newsgroups: comp.arch Subject: Re: *Why* do modern machines mostly have 8-bit bytes? Message-ID: <4957@milano.UUCP> Date: Wed, 22-Jul-87 09:40:51 EDT Article-I.D.: milano.4957 Posted: Wed Jul 22 09:40:51 1987 Date-Received: Fri, 24-Jul-87 04:23:41 EDT References: <142700010@tiger.UUCP> <2792@phri.UUCP> <8315@utzoo.UUCP> <2807@phri.UUCP> Sender: baxter@milano.UUCP Organization: MCC, Austin, TX Lines: 16 Summary: Variable bit size machines I agree, there doesn't seem to be anything magic about 8 bits. If I remember right, the Burroughs 1700 was a microprogrammed machine in which the macroinstruction set (there were several, one per programming language) treated the memory as if it had different bit sizes. The sizes chosen were based pretty much on the expected size of data operands, and on what was effectively a Huffman encoding of the particular macroinstruction set. The microarchitecture did have a fixed size word, with a fancy field extractor used by the microcode to get a the size chunks it wanted. -- -- Ira Baxter Microelectronics and Computer Technology Corporation (512) 338-3795 3500 West Balcones Center Drive, Austin, Texas 78759