Mode parameter header, Mode, Parameter – Dell PowerVault TL2000 User Manual
Page 54: Header
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