Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!ut-sally!husc6!cmcl2!phri!roy From: roy@phri.UUCP (Roy Smith) Newsgroups: comp.arch Subject: Re: machine word sizes Message-ID: <2817@phri.UUCP> Date: Sat, 25-Jul-87 10:17:10 EDT Article-I.D.: phri.2817 Posted: Sat Jul 25 10:17:10 1987 Date-Received: Sun, 26-Jul-87 01:27:13 EDT References: <2807@phri.UUCP> <565@saturn.ucsc.edu> <1184@k.cs.cmu.edu> Reply-To: roy@phri.UUCP (Roy Smith) Organization: Public Health Research Inst. (NY, NY) Lines: 18 In article <1184@k.cs.cmu.edu> lindsay@k.cs.cmu.edu (Donald Lindsay) writes: > The PDP-5, 7, 9, and 15 were 18 bit machines ( 36/2 I'm sure ). The most > visible result of this is the silly tendency to use six-and-three characters > for filenames ( "myfile.bas" ). DEC didn't let the migration to 16-bit words sway them from 6+3 filenames. Au contrare, they simply invented the rad-50 character code so you could pack 3 characters into 16 bits. You got 26 upper-case letters, 10 digits, and 14 random pieces of punctuation. Blech! I don't remember the exact details of rad-50 to ascii conversion, but I seem to recall it being about as complex as 4.3's namei :-) If 4 bits is a nyble, and 8 bits is a byte, is the 5-1/3 bits need to hold a rad-50 character a baubyl? -- Roy Smith, {allegra,cmcl2,philabs}!phri!roy System Administrator, Public Health Research Institute 455 First Avenue, New York, NY 10016