Seagate Ultra 320 - Manual (Page 134)

120 Parallel SCSI Interface Product Manual, Rev. A
Table 47: Task Attribute
[2] The Task Management Flags field is defined in Table 48. If a Task Management function fails, the Task
Manager shall terminate the task with Good status. The packetized failure code shall be set to Task Man-
agement Function Failed.
Table 48: Task Management flags
[3] The Additional CDB Length field contains the length in 4-byte words of the Additional CDB field.
[4] The Write Data (WRDATA) bit and READ Data (RDDATA) bit are defined in SCSI protocol standards T10/
1144D (FCP-2), sections 9.1, 9.1.16, and 9.1.17. They are also discussed in the Seagate Fibre Channel
Interface Manual, part number 77767496. These two bits are used by drives in a Fibre Channel I/O sys-
tem and shall be ignored by this section.
[5] The CDB field contains the actual CDB to be interpreted by the addressed logical unit. The maximum
CDB length is 16 bytes. The CDB field and the task attribute field is not valid and is ignored if the Task
Codes Description
000b
Requests that the task be managed according to the rules for a simple task attribute. See the SCSI
Architecture Model-4 standard .
001b
Requests that the task be managed according to the rules for head of queue task attribute. See the
SCSI Architecture Model-4 standard .
010b
Requests that the task be managed according to the rules for an ordered attribute. See the SCSI
Architecture Model-4 standard .
011b Reserved.
100b
Requests that the task be managed according to the rules for a simple task attribute. See the SCSI
Architecture Model-4 standard .
101b-111b Reserved.
Codes Description
00h Indicates no task management requests for the current task.
01h The task manager shall abort the task as defined in the ABORT TASK message (see Section 4.5.2).
02h The task manager shall abort the task set as defined in the ABORT TASK SET message (see Section
4.5.3).
04h The task manager shall clear the task set as defined in the CLEAR TASK SET message (see Section
4.5.5).
08h The task manager shall perform a hard reset to the selected logical unit as defined in the LOGICAL UNIT
RESET message (see Section 4.5.6).
20h The task manager shall perform a hard reset as defined in the TARGET RESET message (see Section
4.5.7).
40h The task manager shall perform a clear ACA as defined in the CLEAR ACA message (see Section 4.5.4).
All other
values
reserve
d
The task manager shall terminate the task with a Good status. The packetized failure code shall be set to
Task Management Function Not Supported.