Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!njin!spcvxb.spc.edu!terry
From: terry@spcvxb.spc.edu (Terry Kennedy, Operations Mgr.)
Newsgroups: comp.sys.dec
Subject: Re: VAX 730 stuff
Message-ID: <1991Feb8.045950.1087@spcvxb.spc.edu>
Date: 8 Feb 91 04:59:49 GMT
References: <38976@cup.portal.com>
Distribution: na
Organization: St. Peter's College, US
Lines: 34

In article <38976@cup.portal.com>, Azog-Thoth@cup.portal.com (William Thomas Daugustine) writes:
> Next, I thought that 'compatability mode' was built into all the VAX
> 700 processors? Only on some of the later models (6000, etc) is it a
> layered product... If thats the case, the perhaps I am missing some
> files, such as SYS$SYSTEM:RSX.EXE. (doing anything that uses it 
> complains that the file is missing. I searched the drive but couldnt
> find it) Is there anyway I can get a replacement (or whatever one would
> call it), and how? Ive a bunch of software that runs under compatability
> mode, and right now, its rather useless to me...

  Funny, I believe I'm the perpetrator of that compatibility-mode software 8-)

  There are two pieces to being able to run that stuff on a VAX:

  1) Some way of executing PDP-11 instructions.

  2) Some software that pretends to be an RSX-11 operating system.

  The 7xx-series VAXen and the 86x0 have #1 implemented in hardware. VMS
versions prior to V4.0 gave you #2 (you needed it to run some of the VMS
utilities that hadn't been ported to native mode).

  After VMS V4 came out, the RSX compatibility mode software became a
layered product (meaning, send DEC more money). This software product is
called VAX RSX, and the current version is V2.5. Somewhere in the not-so-
distant past, this software was changed to provide a PDP-11 instruction
emulator so it could be used on the newer VAX CPU's.

  So, at the moment you have item #1, but not #2. I don't believe a V3
RSX.EXE will work on V4 of VMS, way too much changed inside VMS.

	Terry Kennedy		Operations Manager, Academic Computing
	terry@spcvxa.bitnet	St. Peter's College, US
	terry@spcvxa.spc.edu	(201) 915-9381