Status - Seagate Ultra160 Product Manual

SCSI Interface Product Manual, Rev. B
7.3

Status

A Status byte shall be sent from the target to the initiator during the STATUS phase at the termination of each
command as specified in Tables 62 and 63 unless the command is cleared by one of the following conditions:
1. an Abort message
2. a Bus Device Reset message
3. a hard reset condition
4. an unexpected Bus Free condition (see Section 3.1.1)
5. an ABORT TASK message
6. a CLEAR TASK SET message
Table 62: Status byte
Bit 7
Byte
0 Reserved
Table 63: Status byte code bit values
Bits of status byte
7 6 5 4 3
R R 0 0 0
R R 0 0 0
R R 0 0 0
R R 0 0 1
R R 0 1 0
R R 0 1 0
R R 0 1 1
R R 1 0 0
R R 1 0 1
R R 1 1 0
All other codes
Key: R—Reserved bit (must be zero for drive)
[1] What was formerly called a "Command Queue" is now called a "Task Set."
[2] Formerly "Command Terminated."
A description of the status byte codes is given below.
Good. This status indicates that the Device Server has successfully completed the task.
Check Condition. This status indicates that an auto contingent allegiance or contingent allegiance condition
has occurred (see Section 7.6.1). Optionally, autosense data may be delivered (see Section 7.6.4.2).
Condition Met. This status shall be returned whenever the requested operation specified by an unlinked
command is satisfied (see the PREFETCH commands in ANSI SCSI Block Commands-2, T10/1417D).
Busy. This status indicates that the logical unit is busy. This status shall be returned whenever a logical unit is
unable to accept a command from an otherwise acceptable initiator (i.e., no reservation conflicts). The recom-
mended initiator recovery action is to issue the command again at a later time.
Intermediate. This status or Intermediate-Condition Met shall be returned for each successfully completed
command in a series of linked commands (except the last command), unless the command is terminated with
Check Condition, Reservation Conflict, Task Set Full, Busy status. If Intermediate or Intermediate-Condition
Met status is not returned, the series of linked commands is terminated and the task is ended.
6 5
2 1 0 Status represented
0 0 R Good
0 1 R Check Condition
1 0 R Condition Met/Good
0 0 R Busy
0 0 R Intermediate/Good
1 0 R Intermediate/Condition Met
0 0 R Reservation Conflict
0 1 R Obsolete [2]
0 0 R Queue Full/Task Set Full [1]
0 0 R ACA Active
Reserved
4 3
Status Byte Code
2 1
Reserved
123
0