Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!xanth!nic.MR.NET!umn-d-ub!rutgers!mcdchg!ddsw1!karl
From: karl@ddsw1.MCS.COM (Karl Denninger)
Newsgroups: comp.dcom.modems
Subject: Re: help - Courier HST doesn't connect to us at 1200 bps
Summary: Grrrrr... The HST has some FATAL design problems for us.
Message-ID: <2460@ddsw1.MCS.COM>
Date: 14 Dec 88 15:47:47 GMT
References: <3630@crash.cts.com>
Reply-To: karl@ddsw1.MCS.COM(Karl Denninger)
Organization: Macro Computer Solutions, Inc., Mundelein, IL
Lines: 35

In article <3630@crash.cts.com> jbritain@pnet01.cts.com (Jim Britain) writes:
>The Courier 9600HST, at times can be rather touchy connecting at lower speeds
>if set to full "automatic" speed and protocol sensing, when calling other
>modems.

This doesn't work in the following scenario:

o Modem connected to Unix machine, which both dials out and receives calls
  inbound.  Calls inbound come from all different speed classes.

Now, with this scenario, you either have a (1) 9600-baud HST which can talk
to a 2400 or 1200 baud MNP unit, and _SOME_ non-MNP modems, or (2) a 2400
baud modem which will NOT take a high-speed call!

U.S. Robotics, this stinks! 

I agree that you should set parameters appropriately for outgoing
connections, but this simply doesn't work for incoming callers.  With the
behavior I've seen, 3b1 systems CANNOT call us with the OBM at all, many
other 1200-baud modems immediately disconnect (yikes!), and SOME others can
connect through after 4-6 second delay.

MNP units calling us work fine; this jives with the manual which claims that
the /ARQ protocol is a MNP-type thing and is interoperable with MNP.

Contrast this with our Telebit, which can connect with ANYTHING on an
inbound call -- PEP _OR_ any and all 300-2400 baud modems.  (It is true that
you have to present PEP tones LAST to do this reliably, but at least you
_CAN_ accomplish it!)

The HST is a much poorer design for the real world given this problem.

---
Karl Denninger (karl@ddsw1.MCS.COM, ddsw1!karl)
Data: [+1 312 566-8912], Voice: [+1 312 566-8910]
Macro Computer Solutions, Inc.    	"Quality solutions at a fair price"