Message Parity E R R O R (09); Linked Command Complete (0A); Linked Command Complete With Flag (0B); Bus Device Reset (0C) - IBM DDRS-39130 - Ultrastar 9.1 GB Hard Drive Specifications

9.1.11 MESSAGE PARITY ERROR (09)
This message is sent from the initiator to inform the file 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 file can determine which message byte has the parity error.
If the file receives this message under any other circumstance, the file will change to BUS F R E E to signal a
catastrophic error. After receiving this message, the file will retry sending the previous message to the initi-
ator.

9.1.12 LINKED COMMAND COMPLETE (0A)

The file 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 file goes to C O M M A N D phase to receive the next command.

9.1.13 LINKED COMMAND COMPLETE WITH FLAG (0B)

The file sends this message to the initiator to indicate that the execution of a linked command with flag bit
set to one has completed and that valid status has been sent to the initiator. After successfully sending this
message, the file goes to C O M M A N D phase to receive the next command.

9.1.14 BUS DEVICE RESET (0C)

This message is sent from an initiator to direct the file to clear all current commands. This message forces a
hard reset condition which will reset the file to an initial state with no operations pending for any initiator.
After receiving this message, the file will go to the BUS F R E E phase.

9.1.15 ABORT TAG (0D)

When the target receives this message successfully, it clears the current I/O process and go to Bus Free. If
the target has already started execution of an I/O process, the execution will be halted. Pending status, data
and commands for other active or queued I/O processes shall not be affected.

9.1.16 CLEAR QUEUE TAG (0E)

All I/O processes for all initiators shall be cleared. All active I/O processes shall be terminated. The target
shall go to the Bus Free phase following successfully receipt of this message.

9.1.17 QUEUE TAG MESSAGES(20h, 21h, 22h)

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SCSI MESSAGE SYSTEM