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HP DDS DRIVES USER GUIDE

into the drive mechanism. A load sequence checks ambient
humidity, the tape format and data integrity. Unless the tape is
blank the tape log, which contains a history of usage of the tape,
is read into the drive’s memory.

The drive will automatically format a blank tape when data is
first written to it. Remember to allow time for the formatting
process when you use a new tape.

Removing a cassette

Before attempting to remove a cassette, ensure that the drive is
not currently in use (the amber Drive Busy indicator must be
unlit).

Press the 

EJECT

 button on the front of the drive (depending on

your operating environment, the 

EJECT

 button may be disabled

while the drive is in use). If the tape is write-enabled, a copy of
the tape log, held in the drive’s memory, is written back to tape.
The drive rewinds to the beginning of the tape, unthreads it,
and ejects the cassette. Several seconds may pass between the
button being pressed and the cassette being ejected, so be careful
not to turn off the computer before the operation is completed.

Write-protecting a cassette

A cassette can be write-protected by sliding the white tab on the
cassette so that the recess is revealed. In this position, data can
be read from the tape but not written to it.

The tape log, which includes a record of data integrity failures,
cannot be updated while the cassette is write-protected. It follows
that the tape log becomes inaccurate if a cassette is used while
write-protected, and the media warning LED status cannot be
relied upon to determine if the cassette needs to be copied and
replaced.

Summary of Contents for Apricot HP DDS DRIVES

Page 1: ...HP DDS DRIVES User Guide NATIONAL ACCREDITATION OFCERTIFICATION BODIES ...

Page 2: ...bject to specification change without notice No part of this manual may be reproduced or transmitted in any form or by any means electronic or mechanical including photocopying and recording for any purpose without the express written permission of the publishers Copyright Apricot Computers Limited 1997 All rights reserved Published by Apricot Computers Limited 3500 Parkside Birmingham Business Pa...

Page 3: ...not vice versa The drive automatically detects the format of the cassette when it is inserted into the drive It has the capability to read and write both DDS uncompressed and DDS DC compressed data and data cartridges The drive writes compressed data by default unless it finds uncompressed data already on the cassette The drive can also write uncompressed data under software control When reading a...

Page 4: ...idly Off Cassette read write On Off Cassette loaded Any Flashing Media Caution signal Any On Hardware error or high humidity Media Caution A media caution signal when the Attention LED amber flashes indicates that the tape may be becoming unreliable although at this point no data has been lost First clean the tape head cylinder with the special cleaning cassette then try the data DDS 1 without com...

Page 5: ...horized maintainer If the drive detects high humidity the tape is automatically ejected As soon as the drive detects that the humidity is at an acceptable level it will return to normal operation When high humidity is detected you should allow approximately 1 hour for the drive to acclimatize before trying again Automatic drive operation To prolong the life of the tape and the drive mechanism the ...

Page 6: ...in use If the tape is write enabled a copy of the tape log held in the drive s memory is written back to tape The drive rewinds to the beginning of the tape unthreads it and ejects the cassette Several seconds may pass between the button being pressed and the cassette being ejected so be careful not to turn off the computer before the operation is completed Write protecting a cassette A cassette c...

Page 7: ...hours of tape movement of a new cassette Every 25 operating hours When the Media Caution signal is displayed When you insert the cleaning cassette the drive recognises it as a cleaning cassette runs it for about 30 seconds then ejects it automatically Each time the cleaning cassette is used the tape advances over an unused portion of the tape If the drive ejects the cleaning cassette immediately a...

Page 8: ...0 0 0 0 0 1 0 0 1 2 0 1 0 3 0 1 1 4 1 0 0 5 1 0 1 6 1 1 0 7 1 1 1 1 shorted 0 open The drive reads the SCSI ID at power up and during self test Data Compression Control Data compression can be controlled through the jumper pin shown above The pin is only monitored at power on and controls whether data compression is enabled by default Any subsequent change to the pin are ignored SCSI connector Pow...

Page 9: ...ing the drive will always decompress compressed data It follows from this that if you wish to use this pin you should set configuration switch 1 on the underside of the drive to ON Terminator Power The drive will provide termination power for the SCSI termination resistors if a jumper is set across the two pins marked Term power as shown in the diagram Configuration switches There is a set of conf...

Page 10: ...ff On Compression disabled at power on The host is allowed to control compression Off Off Compression disabled at power on no host control When switch 1 is on data written to the tape will be compressed without the knowledge of the host Media Recognition System MRS Switch 3 is used to configure the drive to respond to DDS Media Recognition System tapes Switch 3 Meaning On The Media Recognition Sys...

Page 11: ...HP DDS DRIVES USER GUIDE 9 Switches 4 to 8 Switches 4 to 8 are used to specify connectivity and functionality according to host or customer requirements The default settings for all switches is on ...

Page 12: ...20 metre cassette 4 0 Gbyte 1 1 base DDS 2 8 0 Gbyte 2 1 typical 16 0 Gbyte 4 1 max1 125 metre cassette 12 0 Gbyte 1 1 base DDS 3 24 0 Gbyte 2 1 typical Transfer rates DDS 366 Kbyte s 1 1 base 732 Kbyte s 2 1 typical 1464 Kbyte s 4 1 max1 DDS 2 400 Kbyte s 1 1 base 800 Kbyte s 2 1 typical 1608 Kbyte s 4 1 max1 DDS 3 1000 Kbyte s 1 1 base 2000 Kbyte s 2 1 typical 1 Nominal maximum only can be excee...

Page 13: ...MITSUBISHI ELECTRIC PC DIVISION APRICOT COMPUTERS LIMITED 3500 PARKSIDE BIRMINGHAM BUSINESS PARK BIRMINGHAM B37 7YS UNITED KINGDOM Tel 44 121 717 7171 Fax 44 121 717 3692 http www apricot co uk ...

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