Selection Without Atn; Multiple Initiator Environment; Initiator Sense Data; Initiator Mode Select/Mode Sense Parameters - Hitachi HUS151473VL3800 - Ultrastar 73.4 GB Hard Drive Specifications

Target allows disconnect permission to be enabled by the Identify message independent of the initiator's use of arbitration prior
to selection. A non-arbitrating initiator must ensure that disconnect permission in the Identify message is disabled (bit 6=0) for
proper operation.

20.13 Selection without ATN

If the target is selected without ATN signal active, no Identify message is received from the Initiator. In this case the LUN is
identified from the CDB and disconnect permission is disabled. The target does not perform any phase retries. The target still
responds to a subsequent attention condition. However the LUN is not considered to be known if a fatal error is detected dur-
ing the Command phase. That is a Command phase parity error or a fatal message error in response to attention condition dur-
ing Command phase is handled as a Bus Free error with no sense data. The target also knows the use of linked commands if
selected without ATN.
Phase retries may be allowed if a subsequent Identify message is received.

20.14 Multiple Initiator Environment

20.14.1 Initiator Sense Data

Separate sense data is reserved for each I-T-L. Each sense data is maintained independent of commands from other initiators.

20.14.2 Initiator Mode Select/Mode Sense Parameters

A single shared copy of the Mode Select/Mode Sense parameters is maintained by the drive. This includes both the current and
saved parameters.

20.14.3 Initiator Data Transfer Mode Parameter

A separate data transfer mode parameters area is reserved and maintained for each initiator.

20.15 Contingent Allegiance Condition

The contingent allegiance condition shall exist following the return of Check Condition, except for a Check Condition caused
by Invalid LUN. Execution of all queued commands shall be suspended until the contingent allegiance condition is cleared.
The contingent allegiance condition can be cleared by the initiator in one of the following ways:
• By issuing a REQUEST SENSE command to the Target and receiving the sense data. This is the recommended way
• By issuing any other command to the I_T_x nexus that reported the fault
• By issuing an Abort message to the I_T_x nexus that reported the fault. This will also abort the current and queued I/
O process from that initiator
• By issuing a Target Reset message to the Target. This will also abort all current and queued I/O processes
• By generating a RESET condition on the bus. This MUST be the last resort

20.16 Reset

The Reset condition is used to clear all SCSI devices from the bus. This condition takes precedence over all other phases and
conditions. After a reset condition is detected and the reset actions completed, the target returns to a 'SCSI bus enabled' state
that allows the target to accept SCSI commands.
This device uses the Hard reset option as defined in the SCSI-3 standard.
Hitachi Ultrastar 15K147 SCSI Hard Disk Drive Specification
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