Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!cs.utexas.edu!rutgers!faatcrl!jprad
From: jprad@faatcrl.UUCP (Jack Radigan)
Newsgroups: comp.sys.amiga
Subject: Re: Send ZModem and JRComm
Message-ID: <1420@faatcrl.UUCP>
Date: 31 May 90 22:08:21 GMT
References: <4926@daffy.cs.wisc.edu>
Distribution: usa
Organization: FAA Technical Center, Atlantic City NJ
Lines: 17

upl@gumby.cs.wisc.edu (Undergrad Projects Lab) writes:

>Anyway, using JRComm's and the Unix's (yeah, the VAX is running UNIX), everything
>goes fine until I get to 2048 characters.  Then, I get a "Data Sub Packet too
>long" message (ALWAYS!), and the machines kind of dink around until they
>become re synchronized.  Generally, this results in a net time of about half
>an hour to transfers a 50K file!  (ARGH!)  

ZMODEM is a full-flow or streaming protocol, which requires some sort of
flow control if the sender is able to transmit data faster than the modem or
receiver can accept it.  Otherwise, you will need to use a window size to
prevent ZMODEM from overflowing the modem and/or receiver.

I'm not a UNIX head, much less so with VAX, you'll need help from someone
else for that.

  -jack-