From: Jim Gillogly <jim@ACM.ORG>
Date: Sat, 13 Apr 1996 11:14:56 +0800
To: cypherpunks@toad.com
Subject: Answer about bits and bytes
In-Reply-To: <m0u7lBY-0008yHC@pacifier.com>
Message-ID: <199604122104.OAA01053@mycroft.rand.org>
MIME-Version: 1.0
Content-Type: text/plain



jim bell <jimbell@pacifier.com> writes:
>See, I do not challenge the fact that there were plenty of data objects of 
>length other than 8-bits.  The issue is whether or not the people back then 
>actually believed that a correct, official usage of the term "byte" included 
>lengths other than 8.

Reading from the PDP-10 Reference Handbook (DEC, 1971) page 2-30, we read:

	To conserve memory, it is useful to store data in less than full
	36-bit words.  Bytes of any length, from 1 to 36 bits, may be
	entered using a BYTE statement.

		BYTE (N) X,X,X

	The first operand is the byte size in bits.  It is a decimal number
	in the range 1-36, and must be enclosed in parentheses.
	...
	In the following statement, three 12-bit bytes are entered:

	  LABEL: BYTE (12)56,177,N

	This assembles as...

and so on.  The PDP-8 "Introduction to programming" (1970) has similar
remarks, though not as explicit.  On page v in the introduction it says

	o A six-bit byte swap instruction that provides much faster...

and in the description of special periph ops on page D 1-15:

	VBA     6534    BYTE ADVANCE command requsts next twelve bits, data
			ready flag is set.

I suggest you gracefully back off, if it's still possible.

	Jim Gillogly
	Sterday, 22 Astron S.R. 1996, 21:04