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Chapter 7 SCSI Interface
05h: INITIATOR DETECTED ERROR
The INITIATOR DETECTED ERROR message from the host to the autoloader
indicates that an error (such as a parity error) has occurred. Note that the
autoloader does not hinder retry processing. After moving to the STATUS
phase, a CHECK CONDITION is reported. At this point, the sense key is
COMMAND ABORTED.
06h: ABORT
The ABORT message aborts execution of the current autoloader SCSI
command. In other words, after the autoloader completes the command, it goes
to the BUS FREE phase.
07h: MESSAGE REJECT
The MESSAGE REJECT message is returned when a message not implemented
by the host or autoloader is received. When this message is issued before the
MESSAGE IN phase, the autoloader moves to the STATUS phase and a
CHECK CONDITION is reported. At this point, the sense key is COMMAND
ABORTED. If this message is issued after the MESSAGE IN phase, it is treated
as an illegal message.
08h: NO OPERATION
The NO OPERATION message is returned when the host has no valid message
to return to the autoloader in response to an autoloader request.
09h: MESSAGE PARITY ERROR
The MESSAGE PARITY ERROR message from the host to the autoloader
indicates that there was a parity error in the last message from the autoloader.
This message is never returned by the autoloader. If the autoloader receives this
message, it goes to the STATUS phase and a CHECK CONDITION is reported.
At this point, the sense key is COMMAND ABORTED.
0Ch: BUS DEVICE RESET
The BUS DEVICE RESET message interrupts the I/O process with respect to
the autoloader. (Actually, at the interruption is performed at a convenient break
in the operation; for example during a MOVE MEDIUM, when the command is
completed). Note that if this message is received during initialization, the
RESET operation is completed without restarting initialization. When this
message is received in the READY state, only the internal parameters are
initialized and the initialization process is not performed. This message forces
an autoloader RESET condition. When this message is received, the SCSI bus
goes to the BUS FREE phase and a UNIT ATTENTION condition is issued to
all initiators.
23h: IGNORE WIDE RESIDUE
The IGNORE WIDE RESIDUE message is issued to the host from the
autoloader to indicate that the number of valid transferred bytes by the REQ/
ACK handshake in the DATA IN phase is lower than the negotiated transfer
width.
Table 7.2.1.11 : IGNORE WIDE RESIDUE Message Format
Bit
Byte
7
6
5
4
3
2
1
0
0
Message Code(23h)
1
Number of Bytes to Ignore(01h)
