Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!ingr!b11!mcconnel
From: mcconnel@b11.ingr.com (Guy McConnell)
Newsgroups: comp.sys.dec
Subject: Re: DEC to go with 4mm DAT technology ...
Summary: It's just their "line"
Message-ID: <6595@b11.ingr.com>
Date: 16 Nov 89 19:44:12 GMT
References: <12646@cit-vax.Caltech.Edu> <13310019@acf4.NYU.EDU>
Organization: Intergraph Corp. Huntsville, AL
Lines: 19

In article <13310019@acf4.NYU.EDU>, tihor@acf4.NYU.EDU (Stephen Tihor) writes:
> I talk to the product managers at DECUS and the DEC line is that the
> 8mm tapes suffer too many errors and can not be used in a seek and
> access mode like magnetic tapes.  Specifically they do not have good
> error behavoir if you streat them like normal tapes write files then
> EOF and EOV and tape marks then backspacing to the EOV and rewriting it
> with the next HDR label, etc.

  That is just DEC's line.  The error correction code in the 8mm drive is very
  sophisticated and quite good.  They can do file skips and record skips at
  10 times the R/W speed as well.  Specifically, the problem with using them
  on a DEC system is the extreme inefficiency of the TMSCP protocol period,
  which is amplified when using a helical scan device.  You'll find much the
  same thing on the 4mm products.  The good news is that, if they bless the
  4mm devices, they'll have to do something to increase driver efficiency and
  this will benefit the 8mm drives as well.


  Guy D. McConnell