Log sense command (4dh) (continued) – Quantum 10K II User Manual

Page 124

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SCSI Description

Quantum Atlas 10K II Ultra160/m SCSI Hard Disk Drives

5–57

LOG SENSE Command (4Dh) (continued)

Bit

Byte

7

6

5

4

3

2

1

0

0 – 1

Parameter Code

2

DU

DS

TSD

ETC

TMC

LP

3

Page Length (n-3)

4 – n

Parameter Value

Figure 5

−23 Generic Log Parameter − Data Format

Table 5

−24 Generic Log Parameter − Field Descriptions

Field

Description

Parameter Code

A code which uniquely identifies each parameter on a given Log Page.
For example, the code 8002h on the Seek Performance Summary page
reports the average seek time while the same code on the Block
Replacement Summary page reports the number of blocks replaced.
The following pages in this manual contain the lists of applicable
parameters for each Log page.

DU

Disable Update. This parameter is 1 when updates are not enabled.

DS

Disable Save. This parameter is 1 when parameters are not saved by the
drive.

TSD

Target Save Disable. This parameter is 0 indicating that the drive provides
a target-specific way of saving parameters.

ETC

Enable Threshold Comparison. This parameter is always 0. The drive
does not use thresholds for any of its parameters.

TMC

Threshold Met Comparison. This parameter is always 0. The drive does
not use thresholds for any of its parameters.

LP

List Parameter. When 0, indicates that the parameter value for this
parameter is a numeric value. When LP is a 1, it indicates that the
parameter value is an alphanumeric ASCII-string list.
This parameter is always 0.

Parameter Length

Specifies the length, in bytes, of the parameter’s value.

Parameter Value

Contains the parameter’s current value when the PC field of the LOG
SENSE command is 01b.

NOTE:

The DU, DS, TSD, ETC, TMC and LP fields are collectively referred to as the Parameter
Control Byte. This byte generally has a value of 0; however, if the page is non-volatile but
the drive is not spun up or the GLTSD bit is set in Mode Page 0Ah, then the value would
be 20h. If the page is volatile, then the value is 60h.

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