Mitsubishi Electric Apricot HP DDS DRIVES User Manual

HP DDS DRIVES

NATIONAL

ACCREDITATION

OF CERTIFICATION

BODIES

User Guide

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Copyright © Apricot Computers Limited 1997. All rights reserved.
Published by

Apricot Computers Limited
3500 Parkside
Birmingham Business Park
Birmingham B37 7YS

http://www.apricot.co.uk

Printed in the United Kingdom

USING A HP DDS TAPE DRIVE

This document describes the HP DDS-2/3 tape drives. The
software needed to control the drives depends on your operating
environment; ask your supplier for details.

The drive has a built-in compression algorithm which can
typically double, and in some cases quadruple, tape capacity. Data
compression and decompression is transparent to the host
software.

CASSETTE INSERTION SLOT

ACTIVITY

LIGHT

ATTENTION

LIGHT

EJECT BUTTON

The DDS-2 drive uses 120-metre (DDS-2) cassettes and the
DDS-3 drive uses 125-metre (DDS-3) cassettes. Both drives can
use earlier DDS format cassettes (the DDS-3 drive can read
DDS-2 cassettes, but 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 cassette,
the DDS drives automatically distinguishes compressed and
uncompressed data and either decompresses it or passes it through
unaltered as appropriate.

Caution

Use only cassettes bearing the DDS or DDS MRS (Media
Recognition System) symbols; you cannot play audio DAT cassettes
with these drives, even on multimedia systems.

HP DDS DRIVES USER GUIDE 1

DDS-1

(without compression)

Capacity (2:1compression)

DDS-1 60m cassette 1.3 GB 2.6 GB 2.6 GB 2.6 GB

DDS-1 90m cassette 2.0 GB 4.0 GB 4.0 GB 4.0 GB

DDS-2 120m cassette N/S N/S 8.0 GB 8.0 GB

DDS-3 125m cassette N/S N/S N/S 24 GB

Transfer Rate

Max. Sustained Native 183 KB/s 183 KB/s 510 KB/s 1 MB/s

N/S=not supported

DDS-1

(with compression)

DDS-2 DDS-3

Note

To gain full advantage of your DDS drive you should use matching
cassettes. That is, use DDS-3 cassettes with the DDS-3 drive. This
allows the drive to store the maximum amount of data on the tape.

Interpreting the LED indicators

There are two LED (light-emitting diode) indicators on the
drive’s front panel. The Activity (green) and Attention (amber)
LEDs show the status of the drive.

Green Amber Drive status

Flashing Off Power-on, or cassette

Flashing rapidly Off Cassette read/write

On Off Cassette loaded

Any Flashing Media Caution signal

Any On Hardware error or high

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

2 HP DDS DRIVES USER GUIDE

load/unload

humidity