Release unit 17h/57h, Pre-execution checks, Command descriptor block – HP Q153090901 User Manual
Page 135: Byte only, Release unit h/57h 135, Pre-execution checks: command descriptor block
RELEASE UNIT 17h/57h
C
omm
an
ds
135
RELEASE UNIT
17h/57h
R
ELEASE UNIT
enables the host to release any reservation it may have on the drive. Reserving a
device is a way of ensuring exclusive access to that device from a single initiator for the period of
the reservation. The drive may be reserved using a
RESERVE
command.
Pre-execution checks:
Command descriptor block:
6-byte
10-byte
10-byte only
Illegal Field
Deferred Error
Unit Attention
7
6
5
4
3
2
1
0
0
Operation Code (17h)
1
Reserved (0)
3rd Pty
Third-Party Device ID
Rsvd(0)
2
Reserved (0)
4
5
Control
3rdPty
This bit is always zero because third-party reservation is not supported.
Third-Party Device ID This bit is always zero because third-party reservation is not supported.
7
6
5
4
3
2
1
0
0
Operation Code (57h)
1
Reserved (0)
3rd Pty
Reserved (0)
LongID
Rsvd(0)
2
Reserved (0)
3
Third-Party Device ID
4
Reserved (0)
6
7
(MSB)
Parameter List Length
8
(LSB)
9
Control
3rd Pty
0 Third-party release is not requested.
1 The initiator requests third-party release. The value in the Third-Party
Device ID field is valid.