Article View: comp.sys.dec
Article #467Re: PDP-11 movb instruction
From: John T. Coburn
Date: Thu, 29 Jun 1989 01:59
Date: Thu, 29 Jun 1989 01:59
16 lines
942 bytes
942 bytes
In article <2592@blake.acs.washington.edu>, erf@blake.acs.washington.edu (John Firestone) writes... >I am designing a Q-bus controller and have come upon a PDP-11 >architecture question which I hope someone can answer. If >a MOVB instruction writes the low byte of a word-oriented device >register, what does the high byte get set to? > >Thanks in advance for your help. > The high byte would be unchanged if the device register allows byte access. Otherwise the result would be undefined. -- John Employed by, but not representing Digital Equipment Corp.
Technical Details
Message-ID:
<377@mountn.dec.com>Path:
arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!ames!haven!decuac!mountn.dec.com!clo.dec.comShow Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!ames!haven!decuac!mountn.dec.com!clo.dec.com From: coburn@clo.dec.com (John T. Coburn) Newsgroups: comp.sys.dec Subject: Re: PDP-11 movb instruction Message-ID: <377@mountn.dec.com> Date: 29 Jun 89 01:59:52 GMT Sender: news@mountn.dec.com Organization: Digital Equipment Corporation Lines: 16