Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!rutgers!cs.utexas.edu!usc!ucsd!telesoft!rlk
From: rlk@telesoft.com (Bob Kitzberger @sation)
Newsgroups: comp.misc
Subject: Re: PC Process Control Info Needed
Summary: Opto-22
Message-ID: <635@telesoft.com>
Date: 21 Dec 89 02:27:37 GMT
References: <4324@rtech.rtech.com>
Distribution: na
Organization: TeleSoft, San Diego, CA.
Lines: 33

In some article, Fred Buechler writes:
>
>      My uncle is looking for a way to get his PC to monitor a number of analog
> inputs (temperature, pressure, flow rate, etc.) and make adjustments to the 
> devices that control these variables to keep them within specified tolerances.
> 
>      I don't even know where to start looking for hardware/software solutions
> to this problem. 

I've used remote sensing equipment from Opto-22 with very good results (can
someone else provide an address or phone number for Opto-22?)  Their boards
consist of up to 16 devices on a board.  The devices can be selected from a
wide variety of relays, analog to digital converters, event counters, etc.
Each board connects to your PC via an RS-422 line (or RS-232C with a
convertor), and each board is assigned an address so that multiple boards can
hang on the same RS-422 port.  Use of RS-422 allows reliable operation over
much longer distances than RS-232C.  

The boards are programmable, including watchdog timers, checksum verification
before executing a command, etc.  

If the PC will be *controlling* equipment, you'll want to take steps to
increase reliability.  Drop me e-mail for ideas along those lines.

	.Bob.
-- 
Bob Kitzberger                  Internet : rlk@telesoft.com
TeleSoft AB                     uucp :     ...!ucsd.ucsd.edu!telesoft!rlk
5959 Cornerstone Ct. West       at&t :     (619) 457-2700 x163
San Diego, CA 92121-9891        

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