Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!rutgers!uwm.edu!zaphod.mps.ohio-state.edu!swrinde!ucsd!ames!eos!data.nas.nasa.gov!mustang!nntp-server.caltech.edu!tybalt.caltech.edu!toddpw
From: toddpw@tybalt.caltech.edu (Todd P. Whitesel)
Newsgroups: comp.sys.apple2
Subject: Re: hardware handshaking through a modem
Message-ID: <1990Oct6.122802.28306@nntp-server.caltech.edu>
Date: 6 Oct 90 12:28:02 GMT
References: <2092@unsvax.NEVADA.EDU>
Sender: news@nntp-server.caltech.edu
Organization: California Institute of Technology, Pasadena
Lines: 14
Nntp-Posting-Host: tybalt.caltech.edu

When you use the hardware handshake lines, you are telling the modem that
it is ok/not ok to send, but the modem has no way to communicate this fact
to the other end of the phone line. This means that your modem will quit
sending characters, but the modem itself will still be recieving them --
so when the modem's own internal buffer (assuming it has one) overflows,
you lose gobs of characters.

My suggestion would be to have your drivers be able to turn XON/XOFF mode
on or off, so the higher-ups can inform the driver whether or not to use
XON/XOFF. A bigger buffer than 256 characters would also be a good idea if
you are not really tight on memory.

Todd Whitesel
toddpw @ tybalt.caltech.edu