Command Descriptor Block - Tandberg Data SLR7-140 PROGRAMMER Manual

BYTE BIT 7
00 Operation Code 1Ah
01 Logical Unit Number (LUN)
02 PC
03 RESERVED
04 Allocation Length
05 Control Byte
Table 15-1:
DBD
PC
Page Code
Allocation Length
Tandberg Data

15.2. Command Descriptor Block

6 5
Page Code
MODE SENSE Command Descriptor Block
A Disable Block Descriptor (DBD) bit of one indicates
that the Block Descriptor List will not be transferred
to the Initiator. A DBD bit of zero indicates that the
Block Descriptor List will be transferred following the
Header List.
The page control
parameter values to be returned.
0 : Return current values
1 : Return changeable values
2 : Return default values
3 : Return saved values
The page code specifies which page(s) to return.
Legal values are 00h, 01h, 02h, 0Ah, 0Fh, 10h, 11h,
1Ch, 20h, 21h, 22h, 23h and 3Fh
Page Code 00h is returning the Header List followed by
the Block Descriptor List - a total of 12 bytes. When
selecting Page Code 00h the DBD bit is ignored.
See the MODE SELECT command for a description of the
various pages.
This field specifies the maximum number of bytes that
the Initiator has allocated for the returned MODE SENSE
data. An Allocation Length of zero indicates that no
MODE SENSE data will be sent. The Drive terminates the
DATA-IN phase when Allocation Length bytes have been
transferred or when all available MODE SENSE data have
been transferred, whichever is less.
1
The special page code 3Fh can be used to have the Drive return all
its page descriptors.
15-2 Tandberg SLR Product Line SCSI Functional Specifications
4 3 2
R DBD RESERVED
(PC) field defines
1
.
Mode Sense
1 0
the type of