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Space 11h, Pre-execution checks, Command descriptor block – HP Q153090901 User Manual

Page 172: Byte version, Space h 172

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Commands

172

SPACE

11h

S

PACE

provides a variety of positioning functions that are determined by Code and Count fields in

the Command Descriptor Block. Both forward (towards EOM) and reverse (towards BOM)

positioning are provided.

Any unwritten data in the buffer is flushed to tape before the space is started. The logical media

position is then modified according to the Code and Count fields. Once the space has started, it

will complete even if the SCSI operation is aborted for some reason (for example, the host selects

and sends an abort message).

Pre-execution checks:

The Code field must be 0, 1 or 3. If it is not then

CHECK CONDITION

status is reported. Sense data

will be as described in the Illegal Field Checks.

Command descriptor block:

6-byte version

16-byte version

Illegal Field

Reservation

Deferred Error

Unit Attention

Media Access

Diagnostic Status

7

6

5

4

3

2

1

0

0

Operation Code (11h)

1

Reserved (0)

Code

2

(MSB)

Count (n)

3
4

(LSB)

5

Control

7

6

5

4

3

2

1

0

0

Operation Code (91h)

1

Reserved (0)

Code

2–3

Reserved (0)

4

(MSB)

Count (n)

11

(LSB)

12

(MSB)

Parameter Length

13

(LSB)

14

Reserved (0)

15

Control