Path: utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!hayes!tnixon
From: tnixon@hayes.uucp
Newsgroups: comp.dcom.modems
Subject: Re: Clarification on MNP4 and Everex 24+
Message-ID: <3782.27bf04ac@hayes.uucp>
Date: 17 Feb 91 22:33:15 GMT
References: <6819.27BE119B@zswamp.fidonet.org>
Organization: Hayes Microcomputer Products, Norcross, GA
Lines: 32

In article <6819.27BE119B@zswamp.fidonet.org>,
root@zswamp.fidonet.org (Geoffrey Welsh) writes: 

>    Worst case scenario: computer-modem interface locked at 19,200 (or 
> 38,400); menu is a full screen long (2K), and the modem can hold that much in 
> a buffer.  A user calls at 1200 bps.  The menu is sent to the modem (for all 
> intents instantly).  The user, familiar with the system, hits a key as soon 
> as he sees the menu start.  However, the computer has already sent the menu 
> out and is now proceding to act on the user's command... while the user 
> watches 2K of menu stream out at 120 CPS, resulting in an annoying delay.

Ahh!  Now I understand!  Since I never use a BBS with a low speed 
modem (heck, I get Ultra 96's for free, why should I?  :-)  it never 
struck me that this cancellation of a display would be a frequent 
occurrence.  I generally think of ^C'ing something coming from a 
Vax, rather than interrupting a menu display.  Now that you've 
explained it, it makes perfectly good sense -- and now I understand 
why it is such a concern!  Yes, it _would_ be very frustrating, if 
you _knew_ that the menu display was _supposed_ to be interrupted 
when you pressed a key, but it didn't.

Alas, there's nothing I can do about other people's modems but 
advise users to contact the manufacturers are suggest an S-register 
to control the flow-off threshold.  I guess this is one more 
argument in favor of using Hayes modems, since we've kept the 
buffers small (256 bytes, with 192-byte high water mark) all along.

-- 
Toby Nixon, Principal Engineer    | Voice   +1-404-449-8791  Telex 151243420
Hayes Microcomputer Products Inc. | Fax     +1-404-447-0178  CIS   70271,404
P.O. Box 105203                   | UUCP uunet!hayes!tnixon  AT&T    !tnixon
Atlanta, Georgia  30348  USA      | Internet       hayes!tnixon@uunet.uu.net