Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!sdd.hp.com!decwrl!bacchus.pa.dec.com!shlump.nac.dec.com!star.enet.dec.com!parke
From: parke@star.enet.dec.com (Bill Parke)
Newsgroups: comp.arch
Subject: Re: PDP-10 (was: Looking for a really odd computer)
Message-ID: <1990Oct9.150740@star.enet.dec.com>
Date: 9 Oct 90 19:10:28 GMT
References: <1990Oct8.214604.25320@ns.network.com> <2721@crdos1.crd.ge.COM> <2515@ns-mx.uiowa.edu> <71383@sgi.sgi.com>
Sender: newsdaemon@shlump.nac.dec.com
Reply-To: parke@star.enet.dec.com (Bill Parke)
Organization: Digital Equipment Corporation, Nashua NH
Lines: 37

In article <1990Oct8.214604.25320@ns.network.com>, ddb@ns.network.com (David
Dyer-Bennet) writes:
|> From: ddb@ns.network.com (David Dyer-Bennet)
|> Newsgroups: comp.arch
|> Subject: PDP-10 (was: Looking for a really odd computer)
|> 
|> In article <71383@sgi.sgi.com> rpw3@sgi.com (Rob Warnock) writes:
|> [referring to the DEC PDP-10]
|> :I don't recall any production software that used 9-bit bytes, though at
least
|> :one attempt at an experimental C compiler used them.
|> 
|> I seem to recall that the COBOL compiler used them for some modes of
|> character data or character numeric data.  Can't figure out why
|> offhand, though.

	At the time, there was a lot of COBOL applications on some other
	vendors hardware with 4 bytes per word and eight bit encoding.
	9 Bits, holds 8 and works, evenly, 4 bytes per 36 bit word.

	Most ASCII was 5 7 bit bytes, with the bottom bit left over.
	Setting this bottom bit caused lots of things (SOS, compilers etc) to 
	ignore the "line number" (which just happened to be 5 digits).

|> -- 
|> David Dyer-Bennet, ddb@terrabit.fidonet.org
|> or ddb@network.com
|> or ddb@Lynx.MN.Org, ...{amdahl,hpda}!bungia!viper!ddb
|> or Fidonet 1:282/341.0, (612) 721-8967 9600hst/2400/1200/300
|> 
--
Bill Parke 			parke%star.enet.dec@decwrl.dec.com
VMS Development			decwrl!star.enet.dec.com!parke
Digital Equipment Corp		parke@star.enet.dec.com
110 Spit Brook Road ZK01-1/F22, Nashua NH 03063

The views expressed are my own.