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- Path: sparky!uunet!zaphod.mps.ohio-state.edu!cs.utexas.edu!sun-barr!sh.wide!wnoc-kyo!kuis!aegis!davidg
- From: davidg@aegis.or.jp (Dave McLane)
- Newsgroups: comp.dcom.modems
- Subject: Re: V.42bis/LAP-M questions
- Message-ID: <3592@aegis.or.jp>
- Date: 8 Jan 93 23:53:55 GMT
- References: <1993Jan5.213939.11393@uts.uni-c.dk>
- Sender: daemon@aegis.or.jp
- Lines: 35
-
- povlphp@uts.uni-c.dk (Povl H. Pedersen) writes:
-
- >How come that I sometimes have to get retries from Z-modem when
- >using a modem with MNP-5 or V.42bis/LAP-M ? Both include error
- >correction, and I thought that would ensure that all packages
- >would be transfered as sent. I also thought that the RE or TE
- >messages I see on very noisy lines on my Supra V.32bis would
- >mean that the modems resent the packages.
-
- As far as I know Z-modem errors are telling you that something is
- amiss between the modem and your PC. I won't try and guess what's
- happening with your setup but there was one person here who was
- having the same problem and it turned out to be the UART not being
- able to handle the speed (which you didn't specify). It could be
- the software+CPU not being able to handle the data or perhaps the
- cable.
-
- >So, is error correction in modems good ? Or is it something
- >that helps a little on quality ?
-
- Depends what you mean by 'good'. Under plain ASCII transfers error
- correction will eliminate the rubbish but IMO when you get up
- against the wall sometimes it's better to accept a little rubbish
- and get the data instead of having the modems sit there resending
- and resending or giving up and dropping the link entirely.
-
- Dave
-
- --
- Dave McLane
- JUNET: davidg@aegis.or.jp (ONLY within Japan: post otherwise)
- Nagaokakyoshi, Kyoto Japan Tel: +81-75-951-1168 Fax: +81-75-957-1087
-
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-