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From: casey@gauss.llnl.gov (Casey Leedom)
Newsgroups: comp.dcom.modems
Subject: Re: Modems & CTS
Message-ID: <42123@lll-winken.LLNL.GOV>
Date: 21 Dec 89 01:21:45 GMT
References: <25213@cup.portal.com> <1989Dec20.185317.19518@dlb.uucp>
Sender: usenet@lll-winken.LLNL.GOV
Reply-To: casey@gauss.llnl.gov (Casey Leedom)
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Organization: Lawrence Livermore National Laboratory
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| From: dave@dlb.UUCP (Dave Buck)
| 
| [Long description of how RTS/CTS are supposed to be used ``officially'']

Dave,
  I believe that Lance was referring to the popular, but non-standard,
use of RTS/CTS for FULL DUPLEX flow control.  In this scheme, the DTE
(terminal or computer) raises RTS when it is able to receive data and the
DCE (modem) raises CTS when it is able to receive data.  This scheme has
become so popular it has become a de facto industry standard.

  Note again that this is non-standard, but I don't believe that it
causes many problems with the definitions of the signals as you stated
them because, as far as I know, RTS and CTS are for HALF DUPLEX
communications.  Thus all that has been done is to define meanings to RTS
and CTS for FULL DUPLEX communications.

  If I'm talking out of my hat, someone please correct me.  Flames
welcome.  This is something I should have a sounder base in.

Casey