Path: utzoo!mnetor!uunet!husc6!cmcl2!rutgers!cbmvax!grr
From: grr@cbmvax.UUCP (George Robbins)
Newsgroups: comp.dcom.modems
Subject: Re: 'Blazers and slow response
Message-ID: <3277@cbmvax.UUCP>
Date: 6 Feb 88 20:42:32 GMT
References: <188@mccc.UUCP>
Reply-To: grr@cbmvax.UUCP (George Robbins)
Distribution: na
Organization: Commodore Technology, West Chester, PA
Lines: 49

In article <188@mccc.UUCP> pjh@mccc.UUCP (Peter J. Holsberg) writes:
> I have a Telebit TRailblazer on my 3B2/400 and one on my XT clone.
> Whenever, I call the 3b2 from the XT, I experience a strange phenomenum:
> I can type faster than the 'blazers echo the characters to my screen.

The Trailblazers "packetize" that data resulting in some echo delay.
This is something one can usually adapt to in exchange for the overall
improved thruput.

> I use Pro-YAM on the clone with the Blazer at default settings.  The
> Blazer on the 3b2 is set up as per MIchael Ballard's recent postings.
> Anyone have any idea what's happening and how to correct it?
 
> Other symptoms: the screen scroll is quite jerky; ^C is (frequently)
> ignored; ^S stop sthe scroll but ^Q will not restart it, nor does
> sending a BREAK have any effect.

Using flow control and a higher interface rate, may result in some
jerkyness and delay in responding to control/c and other controls that
require action from the remote system, since the modem is buffering
data and doesn't know when to "dump" unwanted output data.  In "text"
mode, you might want to try using S68=4 to enable both hardware and
control/S - control/Q.  Also make sure that you're control/Q isn't
being eaten by the BIOS or communications programs.

What are your flow control settings on the modem on each end?  It is
possible that telebit is doing something nasty...  Having the modem
"pass" control/S's after the first one to the host system, but "eating"
all control/Q's in the modem would be fatal.

TELEBIT:

	You should add a mode S56=0 which means that *any* character
received from the host reenables transmission.  This mode is used by
many interactive systems in place of the strict control/Q - control/S
discipline.

In general:

Remember folks, control/S - control/Q isn't a line discipline, it is
a control sequence for running paper-tape readers on model 33 teletypes.
There are a lot of potential problems where more than one agent in a
communications linkage is trying to interpret and correctly process
control/S - control/Q.

-- 
George Robbins - now working for,	uucp: {uunet|ihnp4|rutgers}!cbmvax!grr
but no way officially representing	arpa: cbmvax!grr@uunet.uu.net
Commodore, Engineering Department	fone: 215-431-9255 (only by moonlite)