Product Manual - Disc Drive SCSI-2/SCSI-3 Interface (Vol. 2; Ver. 2), Rev. E 143
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5.2.1.9.3
Third Party Release
The disc drive supports the third party release option. The third party release option for the Release com-
mand allows an initiator to release a logical unit which was previously reserved using the third party reserva-
tion option (see Section 5.2.1.8.3).
If the third party (3rdPty) bit is zero, the third party release option is not requested. If the 3rdPty bit is one, the
disc drive shall release the specified logical unit, but only if the reservation was made using the third party
reservation option by the initiator that is requesting the release, and for the same SCSI device specified in the
third party ID field.
5.2.1.10
Mode Sense (6) Command (1Ah)
Table 5.2.1-18. Mode Sense Command
Bit
7
6
5
4
3
2
1
0
Byte(s)
0
0
0
0
1
1
0
1
0
1
Logical Unit No. [1]
DBD
0
0
0
0
0 [2]
0
0
0
2
PCF
Page Code
[4]
(See Table
5.2.1-19)[3]
3
0
0
0
0
0
0
0
0
4
Allocation Length
[5]
5
0
0
0
0
0
0 Flag Link[6]
The Mode Sense command provides a means for the disc drive to report its medium, logical unit, or periph-
eral device parameters to the initiator. It is a command complementary to the Mode Select command.
Notes.
This command is implemented in the disc drive with the following drive specific parameters:
[1] The LUN must be zero.
[2] A DBD bit of zero indicates that the drive may return zero or more block descriptors in the returned Mode
Sense data, at the drive’s discretion. Seagate SCSI-2 products return one block descriptor if the DBD bit
is zero. A DBD bit of one specifies that the drive shall not return any block descriptors in the returned
Mode Sense data. Byte 3 of the Mode Sense header contains 00h to indicate a block descriptor length of
zero.
[3] The content of mode parameter bytes is determined by the value of the PCF (Page Control Field) bits
specified in CDB byte 2, bits 6 & 7. The disc drive shall return the same Page Length for each supported
page regardless of the value of PCF. The PCF field is defined in Table 5.2.1-19.
