Mode parameter header, Mode, Parameter – Dell PowerVault TL2000 User Manual

Page 54: Header

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Mode

Parameter

Header

The

returned

data

on

a

Mode

Sense

(10)

command

begins

with

an

eight

byte

Mode

Parameter

Header.

This

header

has

the

following

structure:

Bit

7

6

5

4

3

2

1

0

Byte

0

(MSB)

Mode

Data

Length

1

(LSB)

2

Reserved

3

Reserved

4

Reserved

5

Reserved

6

(MSB)

Block

Descriptor

Length

7

(LSB)

Field

descriptions:

Mode

Data

Length:

This

field

indicates

the

number

of

bytes

of

parameter

information

the

media

changer

is

returning

as

a

result

of

this

command,

excluding

the

Mode

Data

Length

but

including

the

six

additional

Mode

Parameter

Header

bytes.

If

a

block

descriptor

was

requested

this

count

is

also

added

to

the

Mode

Data

Length.

Block

Descriptor

Length:

When

the

DBD

bit

is

set

to

zero

the

media

changer

may

return

an

eight

byte

Block

Descriptor.

When

a

Block

Descriptor

is

returned

the

Block

Descriptor

Length

will

report

8.

When

the

DBD

bit

is

set

the

media

changer

will

not

return

Block

Descriptors

and

the

block

Descriptor

Length

will

report

0.

3-40

TL2000

and

TL4000

SCSI

Reference