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From: dave@westmark.WESTMARK.COM (Dave Levenson)
Newsgroups: comp.sys.att,comp.unix.sysv386
Subject: Hardware Flow Control on tty
Message-ID: <2173@westmark.WESTMARK.COM>
Date: 22 Dec 90 03:53:39 GMT
Organization: Westmark, Inc., Warren, NJ, USA
Lines: 20

I am trying to use a high speed V.32 modem on a tty port using AT&T
SysV/386r3.2.2.  The modem allows the DTE and DCE speeds to differ,
and then offers a choice of flow control methods.

The HARDWARE flow-control option causes the modem to assert CTS
until its buffer is nearly full, and then to drop CTS.  UNIX seems
to ignore the not-CTS state, and continues to send data. Is there
any way to get the UNIX tty device driver to recognize and react to
this signal?

The SOFTWARE flow-control option causes the modem to send X-OFF (^S)
to the the host when its buffer is nearly full, and then to send
X-ON (^Q) when it can again accept data.  In this mode, it is
incompatible with UUCP which wants to send binary data including
X-ON and X-OFF through the modem.
-- 
Dave Levenson			Internet: dave@westmark.com
Westmark, Inc.			UUCP: {uunet | rutgers | att}!westmark!dave
Warren, NJ, USA			AT&T Mail: !westmark!dave
[The Man in the Mooney]		Voice: 908 647 0900  Fax: 908 647 6857