Tandberg Data StorageLibrary LTO-3 SCSI, Руководство пользователя

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SCSI Interface Specification
SCSI Communications
AUTOLOADER LTO3 – User Reference Manual Rev. 1.01 TANDBERG DATA
Page 6 1 of 79
11.2.1 SCSI Messages
The initiator and the target use the SCSI message system to manage the physical path. The following
table lists the messages supported by the autoloa der. One or more messages can be sent during a
single message phase.
Message Hex
Value Description In
1 )
Out
2 )
Command
Complete 00h The autoloader informs the initiator that the
command was executed and that it sent a valid
status byte to the initiator. x
Synchronous data transfer request (01h)
The initiator starts negotiations for synchronous
data transfer. The autoloader negotiates down
to asynchronous data transfer. x x Extended
3 )
01h
Wide Data Transfer Request (03h)
The initiator starts negotiations for wide data
transfer. The autoloader negotiates down to
narrow data transfer. x x
Save data
pointers 02h The autoloader sends a Save Data Pointers
message to the initiator before processing a
disconnect message following a Data In or
Data Out phase. x
Restore
Pointers 03h The autoloader informs the initiator that it did
not properly receive a block of data or the
command descriptor block (CDB) and that the
data needs to be transferred again. x
Disconnect 04h The autoloader informs the initiator that it plans
to disconnect from the SCSI bus and that a
reconnect will be required later. x
Initiator
detected
error 05h The initiator informs the autoloader that an
error occurred. The autoloader can retry the
operation. x
Abort 06h The initiator is cl earing the present and any
pending operations for that initiator. When the
autoloader accepts this message, it releases
the bus into the bus free phase. x
Message
reject 07h Either the initiator or the autoloader is
indicating that the last message recei ved was
inappropriate or not implemented. x x
No
operation 08h The initiator informs the autoloader that it does
not have a valid message to send in response
to the autoloader's request for a message. x
Message
parity error 09h The initiator informs the autoloader that one or
more bytes in the last message it received had
a parity error. x