Specifications

ATAPI For Streaming Tape QIC-157 Rev B

Table 6-53 Compression Algorithm Identifier

Algorithm Identifier Description

00h No Algorithm Selected (Identifies uncompressed data)

01h Unused

02h - 0Fh Not assigned

10h IBM IDRC Data Compaction Algorithm

11h - 1Fh Not assigned

20h DCLZ Data Compaction Algorithm

21h - FDh Not assigned

FEh Reserved

FFh Unregistered Algorithm

100h - FFFFFFFFh Reserved

6.8.8.64.Medium Partition Page Code 11h

Table 6-54 Medium Partition Page

Bit

Byte

7 6 5 4 3 2 1 0

0 PS Reserved Page Code (11h)

1 Page Length (6)

2 0 (Maximum Additional Partitions)

3 0 (Additional Partitions Defined)

4 FDP 0 (SDP) 0 (IDP) 00 (PSUM) Reserved

5 Medium Format Recognition

6 Reserved

7 Reserved

This page is used to specify the medium partitions.

A Fixed Data Partitions (FDP) bit of one indicates that the Device assigns partitions based on its fixed

definition of partitions. Setting this bit to one may only be valid at beginning-of-partition.

Implementor's Note:

1. The FDP bit is used to indicate that the Device will assign partitions based on a pre-defined

(format-specific) definition of the data and directory partitions.

2. If the FDP bit is set to one, the Device shall implement a maximum of two partitions for the QFA

function (a data partition 0 and a directory partition 1).

3. The FDP bit cannot be changed when the tape is positioned away from BOT.

4. Devices indicate support for QFA through the Capabilities and Mechanical Status page.

5. If the Device can detect that an inserted cartridge has been previously recorded as a QFA tape,

the Device shall report the FDP bit as a one in Mode Sense. If the Host issues a write command

from the BOT position without first issuing a Mode Select or Mode Sense, the FDP bit is reported

as a zero and the tape will not be partitioned. This may require new bursts be written.

Implementor's Note: Since defining partitions may require re-formatting the medium for some

implementations, an implicit write to the medium may occur as a result of a MODE SELECT

command that supplies any of these parameters.