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From: harry@demon.co.uk (Harry Broomhall)
Newsgroups: comp.dcom.telecom
Subject: Re: RS484 Data Link Protocol
Message-ID: <16260@accuvax.nwu.edu>
Date: 21 Jan 91 00:46:34 GMT
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X-Telecom-Digest: Volume 11, Issue 44, Message 7 of 11


In article <16005@accuvax.nwu.edu> Dave Price <dap@cs.aber.ac.uk>
writes:

>A research group here has come up against a possible (likely?)
>requirement to implement RS484 data Link protocol.

>Has anyone got experience of this protocol, what it entails and how
>long (man days etc) it might take to implement. I have checked several
>text books in my possession and I cant yet find any references to it.

>In our circumstance it will need to be implemented over a point to
>point link.

    I have found reference to this in my indexes.

1)  All RS numbers are now refered to as EIA numbers.

2)  EIA484 can be got from American Technical Publishers,
    Hitchen, Herts  (tel 0462-37933) in the UK.

3) It is described as: 'Electrical and Mechanical Interface
characteristics and Link Control protocol using communication control
characters for serial data link between a direct numerical control
system and numerical control equipment employing asynchronous full
duplex transmission'
  
     The price in my 1988 catalogue is 17 pounds, which means that it
is not very big, so should not be too difficult for a comms guru to
implement!


Regards,

Harry