DAT 72 (Models 5242 and 5242ACL) Tape Drive User's Guide

Section 1: General Information
Chapter Two
2.1 SCSI Compatibility
5242 and 5242-ACL tape drives comply with the American National Standard Institute (ANSI) standard
X3.131-1986 (SCSI-1) and the ANSI standard X3T9.2 (SCSI-2). These standards define the specifications for
the Small Computer System Interface (SCSI). As defined by the ANSI, SCSI is essentially an input/output
bus for interconnecting computers and peripherals.
2.2 DAT72 Format and Compatibility
5242 and 5242ACL DAT72 format is an extension of the DDS-3 format. DDS formats have been developed
to provide data storage for computers by using and extending DAT technology. DAT72 allows 36 GB of
uncompressed data to be stored on a DAT72 (170m) cartridge. Data compression can increase the cartridges
native capacity. A compression ratio of 2:1 raises the capacity of the cartridge to 72 GB.
• The DAT72 format allows compressed data to be stored in a way that maintains the full functionality
of the DDS-3 format and ensures backward compatibility in reading and writing with existing 5142
and 5142ACL DDS-3 tape drives.
• The drive automatically decompresses data even if data compression is switched off.
• DDS-3 tapes written on a DAT72 drive are readable on a DDS-3 drive; however, a DAT72 tape (170
meters) is not readable on a DDS-3 drive. A DDS-3 drive (both single drive and ACL models)
automatically ejects a DAT72 cartridge. An ACL unit ejects the cartridge into the magazine but does not
unload the magazine. Additionally, the ACL displays: TAPE FAULT: TRY NEW TAPE.
• The DAT72 format uses the same error correction techniques as the DDS-3 format. It incorporates the
error correction techniques used in DAT drives with additional techniques designed to provide superior
data integrity.
HP StorageWorks DAT 72 (Models 5242 and 5242-ACL) User's Guide 5 HP Part Number 528296-03 July 2005