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From: HAL/MISSLINKS/MikeB%Traveling_Software;_Inc.@MCIMAIL.COM (MikeB)
Newsgroups: comp.dcom.modems
Subject: Hardware Flow Control
Message-ID: <42910619180524.0004025717NB2EM@mcimail.com>
Date: 19 Jun 91 18:05:00 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Organization: The Internet
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I'm curious how exactly the RTS/CTS handshaking flow control works between a 
PC and a modem. From what I've seen the following is true:

o The CTS is asserted when the modem buffer is full (256 bytes?).
o If a PC asserts RTS, it causes the *remote* modem to stop sending data 
although a few bytes still get through.
o There is no way to signal the local modem to stop sending data.

Are these statements true in general? Are there modems that do the RTS/CTS 
handshaking differently? Why is RTS implemented that way? For a programmer 
writing a modem interface protocol, what is the best to way to handle 
hardware flow control?

I anxiously await any responses...