Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!princeton!njsmu!mccc!pjh
From: pjh@mccc.edu (Pete Holsberg)
Newsgroups: comp.unix.sysv386
Subject: Re: RTS/CTS (was re: Help Telebit and SCO RTS/CTS Setup)
Keywords: RTS/CTS Hardware Flow Telebit RS-232 Unix 386 SCO
Message-ID: <1991Apr10.125258.16719@mccc.edu>
Date: 10 Apr 91 12:52:58 GMT
References: <1991Apr7.024322.4465@netcom.COM> <1991Apr8.173125.22219@mccc.edu> <21301@ists.ists.ca>
Organization: The College On The Other Side Of Route One
Lines: 25

In article <21301@ists.ists.ca> aronb@gkcl.UUCP (Aron Burns) writes:
=In article <1991Apr8.173125.22219@mccc.edu> pjh@mccc.edu (Pete Holsberg) writes:
=>at various speeds and published the results.  They said that at higher
=>transfer rates (57.6K and 115.2K), they used RTS/CTS handshaking because
=>(I'm paraphrasing) that's what you had to use when you had high speed
=
=Many devices don't respond quickley to an XOFF request, so the 
=buffer on the requesting device overflows with resultant data loss.
=This is particularly true of the UART built in to microcomputers.
=
=Some smart i/o cards respond to XOFF quickly enough to 
=do software flow control at high data rates.  The modem 
=also has to respond quickly.  If it all works, you can save
=some money on cabling :-).

They did their tests with null modems, and several of the comm programs
that choked with RTS/CTS turned on had excellent data transfer rates
with RTS/CTS turned off.  What does this tell us?

Pete
-- 
Prof. Peter J. Holsberg      Mercer County Community College
Voice: 609-586-4800          Engineering Technology, Computers and Math
UUCP:...!princeton!mccc!pjh  1200 Old Trenton Road, Trenton, NJ 08690
Internet: pjh@mccc.edu	     Trenton Computer Festival -- 4/20-21/91