IBM IC35L018UCDY10, Specifications

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11.1.5 Unit Attention Condition
The drive will generate a unit attention condition for each initiator under the following conditions:
!
The drive has been reset. This includes Power On Reset, SCSI Bus Reset, and TARGET RESET
message.
!
The transceiver mode has been changed.
!
The mode parameters in effect for this initiator have been changed by another initiator.
!
The log page parameters have been cleared by LOG SELECT command with PCR bit. In this case a
unit attention condition is generated for all initiators except the one that issued the command.
!
The registration or reservation made by send PERSISTENT RESERVE OUT command is cleared by
another initiator. In this case a unit attention condition is generated for all initiators that the
registration or reservation is cleared except the one that issued the command.
!
The device identifier information is set by SET DEVICE IDENTIFIER command. In this case a unit
attention condition is generated for all initiators except the one that issued command.
!
FORMAT UNIT command has been completed. In this case a unit attention condition is generated
for all initiators except the one that issued command.
!
The microcode has been changed. WRITE BUFFER command has been executed to download
microcode. In this case a unit attention condition is generated for all initiators except the one that
issued the command.
!
Commands are cleared by another initiator. This condition is generated against the initiator that has
queued commands if
–
CLEAR TASK SET message is received.
–
Contingent Allegiance Condition is cleared when Err (Mode Page A) is 01b.
–
DQue (Mode Page A) is set to one while queued command exist .
!
PFA threshold has been exceeded when Method of Reporting defined in Mode Page 1Ch is 2h
(Generate unit attention).
If the drive receives a command from each initiator before reporting a CHECK CONDITION status for
a pending unit attention condition for that initiator, the response of the drive varies with the command as
follows:
INQUIRY The drive executes the command with a GOOD status and preserves the unit
attention condition.
REPORT LUNS same as above.
REQUEST SENSE If the drive has an available pending sense data for the initiator, the drive sends
the pending sense data and preserves the unit attention condition for the initiator.
If the drive does not have an available pending sense data for the initiator, the
drive sends sense data for the unit attention condition and clears the unit
attention condition for the initiator.
Note : the drive sends sense data for the unit attention condition in spite of setting
of UAI jumper or UAI (Mode Page 0).
ALL OTHER The drive terminates the command with a CHECK CONDITION status and
preserves the unit attention condition.
See Section 11.15 "Contingent Allegiance Condition" on page 209 for the drive responses when it
receives a command from an initiator after reporting a CHECK CONDITION status for a pending unit
attention condition for that initiator.
Ultrastar 146Z10 hard disk drive specifications
196