Xref: utzoo misc.wanted:1688 comp.dcom.lans:954
Path: utzoo!utgpu!water!watmath!clyde!rutgers!mit-eddie!uw-beaver!tektronix!reed!percival!gary
From: gary@percival.UUCP (Gary Wells)
Newsgroups: misc.wanted,comp.dcom.lans
Subject: Re: PC as RS232 Data Analyzer
Message-ID: <1063@percival.UUCP>
Date: 26 Jan 88 00:06:51 GMT
References: <2473@emory.uucp>
Reply-To: gary@percival.UUCP (Gary Wells)
Organization: Percy's UNIX, Portland, OR.
Lines: 33


In article 2600 of misc.wanted Ken Mandelberg asks:

>In the serial RS232 world, I have seen a number of special purpose data
>analyzers, which seem quite expensive. Although I suppose they do other
>things, a big piece of their functions is just accurately logging the
>traffic in both directions, and triggering on certain sequences. It
>seems to me that a PC with two serial interfaces could do much the same
>thing, and that the software is not especially tricky.

>Has anyone seen a product of this sort?

You don't even need 2 ports, just one.  Most EIA (RS-232) drivers will handle
a "bridged" connection, that is, will source multiple recievers.  Just build
yourself a Y cable, and run your PC communications program in capture mode.
If possible, have it display, not act upon, control sequences.  

If you wanted to get fancy, you could build a little repeater, using line driver
chips (4888, 4889).  Various companies make these (both repeaters and Y's) under various names (like password grabber, Y, slave terminal driver, etc).  I find 
this method more reliable ( not to mention cheaper) than the Spectron 601 Line
Analsyer we have at work.

What you don't get this way, is the abiltiy to trigger events from selected
character sequences in the monitored stream, or the ability to translate one
set of control codes into another.  Most data analysers do these things, and 
more.  On the other hand, I've never needed that ability.


-- 
--------------------------------------------------------------------------------
Still working on _natural_ intelligence.

gary@percival