Technical information

HGST Ultrastar C15K600 Hard Disk Drive Specification
242
18.33.3
Command timeouts descriptor format
18.33.3.1
Overview
The command timeouts descriptor (see Table 215) returns time-out information for commands supported by the
logical unit based on the time from the start of processing for the command to its reported completion. Values
returned in the command timeouts descriptor do not include times that are outside the control of the device server
(e.g., prior commands with the IMMED bit set to one in the CDB, concurrent commands from the same or different
I_T nexuses, manual unloads, power-on self tests, prior aborted commands, commands that force cache
synchronization, delays in the service delivery subsystem).
For commands that cause a change in power condition (Idle/Standby Powersave Modes), values returned in the
command timeouts descriptor do not include the power condition transition time (e.g., the time to spinup rotating
media).
Values returned in the command timeouts descriptor should not be used to compare products.
Table 222 Command timeouts descriptor format
Byte
7
6
5
4
3
2
1
0
0 - 1
Descriptor Length (0Ah)
2
Reserved = 0
3
Command Specific
4- 7
Nominal Command Processing Time-out
8 - 11
Recommended Command Time-out
The DESCRIPTOR LENGTH field indicates the number of bytes that follow in the command timeouts descriptor.
The COMMAND SPECIFIC field contains time-out information (see Table 216) that is specific to one or more
commands.
If no command specific time-out information is defined by this or the applicable command standard, the
COMMAND SPECIFIC field is reserved.
Table 223 Command timeouts descriptor Command Specific Field usage
Command Reference
WRITE BUFFER
See Section 18.34.3.2 "WRITE BUFFER: command timeouts descriptor COMMAND
SPECIFIC field usage"