HP C737990900 - Manual (Page 19)

Interface Implementation 19
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to ABORTED COMMAND with additional sense of 4800h (Initiator Detected
Error).
If the subsequent message is rejected with an Message Parity Error, then the
drive goes to Status phase and sends CHECK CONDITION status. The sense key
is set to ABORTED COMMAND with additional sense of 4300h (message
error).
On detecting a bus parity error during a Message Out phase, the drive will
handshake in all message bytes until ATN is deasserted. It will then stay in
Message Out phase to indicate to the initiator that the whole Message Out
phase should be resent.
Disconnect Strategy
(Parallel SCSI only)
The disconnect strategy used by the drive is based on the assumption of
maximizing bus utilization for large sequential data transfers from a large data
buffer. The drive will disconnect whenever it believes that it will provide better
bus utilization. This may be between command and data phases, between
bursts of data or before sending status. However, the drive will guarantee that
it will send the configured maximum burst size or the remaining data in the
transfer in any single data phase burst if the maximum burst size has been set
to a value other than zero.
Multi-Initiator Support
All drives will support at least two initiators on the same bus. If more initiators
are supported, all features are supported for the supported number of
initiators.
The drive supports untagged queueing when operating with multiple initiators.
If a command from one initiator is being processed when a command, other
than TEST UNIT READY , INQUIRY , REPORT LUNS and REQUEST SENSE , is
received from a second initiator, then the drive will disconnect and the new
command is queued. Commands other than these from different initiators are
always executed in strict order of receipt. If the queue is full or disconnect
privilege is not granted in the new command, the drive will report BUSY status.
T EST UNIT READY , INQUIRY , REPORT LUNS and REQUEST SENSE commands are
always processed immediately, irrespective of whether a command from
another initiator is being processed.
The drive will maintain sense data for the supported number of initiators. If an
additional initiator connects to the drive, the drive will erase all sense data for