Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site genrad.UUCP
Path: utzoo!linus!vaxine!wjh12!genrad!john
From: john@genrad.UUCP (John Nelson)
Newsgroups: net.unix
Subject: Re: transmitting BREAK
Message-ID: <3864@genrad.UUCP>
Date: Tue, 21-Feb-84 09:00:44 EST
Article-I.D.: genrad.3864
Posted: Tue Feb 21 09:00:44 1984
Date-Received: Wed, 22-Feb-84 04:01:14 EST
References: <16800@sri-arpa.UUCP>
Organization: GenRad, Bolton, Mass.
Lines: 2

You could always try setting the baud rate as low as possible
(50 baud?) and transmitting a NULL