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From: tnfw0@isuvax.iastate.edu
Newsgroups: comp.sys.atari.8bit
Subject: Re: Zmodem?
Message-ID: <1991Jun15.043136.11938@news.iastate.edu>
Date: 15 Jun 91 04:31:36 GMT
References: <6193@mindlink.bc.ca>
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In article <6193@mindlink.bc.ca>, Tom_Klok@mindlink.bc.ca (Tom Klok) writes:
>Zmodem, like all windowed protocols, requires that the computer can talk to the
>modem and talk to the drive at the same time.  That's possible under some
>circumstances, like using a MIO serial port or a ramdisk.  But for most people
>who have SIO modems and drives, it's pretty much impossible.

Actually, the Zmodem protocol had that possible limitation in mind and supports
systems that do not have modem/disk overlap capability. The zmodem protocol
specifications specifically mention that zmodem will work under this
limitation.

>Someone might write it, but it would be wierd.  Zmodem is a lot more complex to
>implement than, say, Ymodem, it gives only slightly better performance, and it
>would only work on a very small subset of Atari 8bit systems.  Who'd bother?

Yes, it is much more complex than other protocols, but a subset could be
implemented that would give enough flexibility to satisfy hobbyists. In my
case, performance is not the overriding factor, but rather the fact that Zmodem
does not require complete transparency over the transmission network. This
comes into play when transferring over Internet. Kermit suffices, but it
unbelieveably inefficient.

As for who would bother, I'm not really sure :) I _might_ bother, but I don't
know if I will. Bob Puff told me it was on his to do list for BobTerm, but that
he does not have the time to work on it now.

>Tom
>
>a344@mindlink.bc.ca

                            Steven Ourada