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From: dg@lakart.UUCP (David Goodenough)
Newsgroups: comp.mail.uucp,comp.dcom.modems
Subject: Re: UUCP Protocols, "efGxd" ... and a Telebit Trailblazer Question.
Message-ID: <747@lakart.UUCP>
Date: 9 Nov 89 16:15:44 GMT
References: <1014@icus.islp.ny.us>
Followup-To: comp.dcom.modems
Organization: Lakart Corporation, Newton, MA
Lines: 21

lenny@icus.islp.ny.us (Lenny Tropiano) sez:
> What if one assumes they have RTS/CTS hardware flow control on both 
> end-points?  Wouldn't that prevent against serial port overrun
> problems with the modem sending too much to the system?

That will only help the modems from being overrun. One problem with
RS232 is that it is not symmetrical: the terminal doesn't have a CTS
equivalent to tell the modem to wait a while. Sure, you could drop DTR,
but most modems will stop sending with extreme prejudice if you do that:
they hang up :-(

It is always assumed that DTE can accept data as fast as the modem
can send it. Why else did I have my 19th. nervous breakdown writing
an interrupt driven serial I/O driver for my CP/M machine, so that it
could do nice things with a V.32 MNP 9 modem at 19.2 KBPS, and the
system at work? (And you should see those two swapping mail :-) )
-- 
	dg@lakart.UUCP - David Goodenough		+---+
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