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LOCATE Command (2Bh) SDLT 600 SCSI Interface Guide

4-30 January 2005 81-81200-02 REV A01

4.6 LOCATE Command (2Bh)

The LOCATE command performs high-speed positioning to a specified block address. Use the READ

POSITION command to obtain the block address associated with the current position on tape. Then

use the LOCATE command to position the tape at the same logical position for high-performance

restore operations of particular blocks of data.

Figure 4-13. LOCATE Command Descriptor Block — Data Format

Bit

Byte

7 6 5 4 3 2 1 0

0 Operation Code (2Bh)

1 Reserved BT CP Immed

2 Reserved

3 – 6

(MSB)

Logical Object Identifier

(LSB)

7 Reserved

8 Partition

9 Control

Table 4-17. LOCATE Command Descriptor Block — Field Descriptions

Field Name Description

BT Block Type. The drive ignores this bit.

CP Change Partition. The drive does not support multiple partitions.

Always set to 0.

Immed Immediate. When set to 1, the drive returns status as soon as the

operation starts. When set to 0, the drive returns status after the

operation has completed.

Logical Object

Identifier

Specifies the Logical Object Identifier to which the drive positions the

medium.

Partition Not applicable; the drive ignores this bit. See CP field above.

SDLT 600

SCSI Interface Guide

SCSI Commands

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REV A01

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