Abort (06H); Message Reject (07H); No Operation (08H); Message Parity Error (09H) - IBM IC35L036UWDY10 - Ultrastar 36.7 GB Hard Drive Specifications

10.1.9 ABORT (06h)

This message is sent from the initiator to direct the drive to clear the present operation for this initiator and
logical unit including queued command(s). If a logical unit has been identified, then all pending data and
status for the issuing initiator and this logical unit will be cleared and the drive will go to the BUS FREE
phase. Pending data and status for other logical unit and initiators will not be cleared. If a logical unit has
not been identified, the drive will go to the BUS FREE phase without affecting an operation on any logical
unit for this initiator or any other initiator. In either case no status or ending message will be sent to the
initiator for this operation. It is not an error to send the ABORT message to a logical unit that is not
currently performing an operation for the initiator.
Note: It is permissible for an initiator to select the drive/LUN after the drive has disconnected from the initi-
ator for the purpose of sending an IDENTIFY message followed by an ABORT message. This will abort
the command on the specified logical unit.

10.1.10 MESSAGE REJECT (07h)

This message is sent from either the initiator or the drive to indicate that the last message received was
inappropriate or has not been implemented.
If the initiator intends to send this message, the initiator must assert the ATN signal prior to its release of
ACK for the REQ/ACK handshake of the message byte that is to be rejected. This provides an interlock so
the drive can determine which message is rejected.
If the drive intends to send this message, the drive will change to the MESSAGE IN phase and send the
MESSAGE REJECT message to the initiator prior to transferring any additional message bytes (or any
other information phase bytes) from the initiator regardless of ATN signal. This provides an interlock so
the initiator can determine which message is rejected. After the drive sends a MESSAGE REJECT
message and if ATN signal is still asserted, it shall return to the MESSAGE OUT phase. The subsequent
MESSAGE OUT phase shall begin with the first byte of a message.

10.1.11 NO OPERATION (08h)

This message is sent from the initiator to the drive when the initiator does not currently have any other
valid message to send. This message is ignored by the drive and will not affect any operation.

10.1.12 MESSAGE PARITY ERROR (09h)

This message is sent from the initiator to inform the drive that the last message byte received had a parity
error.
If the initiator intends to send this message, the initiator must assert the ATN signal prior to its release of
ACK for the REQ/ACK handshake of the message byte that has the parity error. This provides an interlock
so the drive can determine which message byte has the parity error.
If the drive receives this message under any other circumstance, the drive will change to BUS FREE to
signal a catastrophic error. After receiving this message, the drive will retry sending the previous message
to the initiator.

10.1.13 LINKED COMMAND COMPLETE (0Ah)

The drive sends this message to the initiator to indicate that execution of a linked command (with flag bit
equal to zero) has completed and that valid status has been sent to the initiator. After successfully sending
this message, the drive goes to COMMAND phase to receive the next command.
Ultrastar 146Z10 hard disk drive specifications
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