Path: utzoo!attcan!uunet!husc6!uwvax!oddjob!ncar!noao!bull
From: bull@noao.arizona.edu (Frank Bull   CCS)
Newsgroups: comp.periphs
Subject: Re: Helical-Scan Query
Message-ID: <748@noao.UUCP>
Date: 14 Jun 88 16:58:52 GMT
References: <2648@usceast.UUCP> <9807@oberon.USC.EDU>
Reply-To: bull@noao.arizona.edu.UUCP (Frank Bull   CCS)
Organization: National Optical Astronomy Observatories, Tucson AZ
Lines: 19


In article <2648@usceast.UUCP> baldwin@usceast.UUCP (Chuck Baldwin) writes:
>     The following reply, from David Lesher:
>>there is NO way to
>>verify (read after write) on a vcr [besides stopping the tape,
>>going back to the beginning, reading and comparing, etc]

From the Product Specification manual, EXB-8200 8MM Cartridge Tape
Subsystem, Exabyte Corp.

"During WRITE operations, the EXB-8200 CTS records servo information and
formatted user data blocks on the same track and performs a read-after-
write check of the recorded user data.  In the event of an error during 
the read-back check for a WRITE error condition, error recovery procedures
are performed without host intervention, and without the need to reposition
the tape."

The "Read" head is positioned 180 degrees from the "Write" head and
does a read-back-check during the 2nd 180 degrees of head rotation.