Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!mintaka!geech.gnu.ai.mit.edu!dbert
From: dbert@geech.gnu.ai.mit.edu (Douglas Siebert)
Newsgroups: comp.sys.mac.comm
Subject: Re: Problems using ZTerm and sz/rz
Message-ID: <1991Mar24.201920.20823@mintaka.lcs.mit.edu>
Date: 24 Mar 91 20:19:20 GMT
References: <1970001@hpcc01.HP.COM>
Sender: daemon@mintaka.lcs.mit.edu (Lucifer Maleficius)
Organization: The Internet
Lines: 63

In article <1970001@hpcc01.HP.COM> okamoto@hpcc01.HP.COM (Jeff Okamoto) writes:
>I'm having a strange problem with ZMODEM file transfers and am
>wondering if anyone can help.
>
>I'm using ZTerm 0.85 on a Mac II running 6.0.5 with a fair number of
>INIT's.  I have a Racal-Vadic 9600 baud modem which speaks V.32
>connected to the modem port.  On the Unix machine at work, I'm using
>sz version 3.03 5-09-89 and rz version 3.00 4-19-89.  The bank of
>modems that eventually connect to the Unix machine are connected
>via a dialback system.
>
>The symptom: when uploading both text and binary files, I will get
>ZRPOS errors which will eventually cause the file transfer to fail.
>For a while, these consistently occurred after 1024 bytes had been
>transferred, but recently, the transfer went as far as 20K before
>the ZRPOS's started.  The weird part is that downloading text and
>binary files has never failed (yet).
>
>I have tried forcing the mode of the transfer with options to rz and
>options in ZTerm.  I believe I have also tried escaping control
>characters (-e option to rz).  I have tried cutting down the packet
>size in ZTerm to 256 characters.  None of these seems to make any
>difference.
>
>The ROM in my modem WAS recently upgraded, and the time of the change
>vaguely corresponds to the difficulties I'm having.  I do not believe
>any of the non-volatile settings were changed.  I also don't quite
>understand why, if this is the true cause of my problem, I should
>still be able to download, but not upload.
>
>To add to the craziness, just last night, I managed to upload a small
>binary file and it came through okay.
>
>My first question is: what would cause rz to begin issuing ZRPOS's?
>My second question is: why is this happening?
>
>The EC (error correction) LED on the modem is on while I am connected.
>I believe the modems are using MNP5.  The cable connecting my modem to
>the Mac is a standard cable (ie, it isn't a hardware handshake-capable
>cable).
>
>I would appreciate any help or suggestions that you might have to
>offer.


I had this problem before also the first time I ever tried to upload a file
using Zmodem.  The fix I used was to simply use "rz -e" at the unix end to
escape all control characters.  In Zterm I think in the Zmodem settings part
you can change the receive command it sends, so just add a "-e" before the
carriage return and you *should* have no problems.  But I won't guarantee that,
because once doing that didn't fix that problem when I routed through a couple
of machines before my eventual destination, which is strange because the route
(the *shortest* one I can take) involves going through a Gandalf modem server
thingy and then through an annex and on to my destination.  With all that in
between the unix system and myself I can't figure out why another machine or
two in between would muck things up.  Oh well, just try the -e and see if that
works.

--
________________________________________________________________________
Doug Siebert                                     dbert@gnu.ai.mit.edu
MBA Student (2nd year)
The University of Iowa