Tandberg Data VXA-320 (VXA-3) - Manual (Page 54)

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P RODUCT M ANUAL 433689-01
C
HAPTER
6 C
OMMUNICATION
I
NTERFACE AND
C
OMMAND
P
ROTOCOL
SCSI I
NTERFACE
R
EQUIREMENTS
The VXA-320 tape drive is available with a wide, High-density (HD) 68-pin,
low-voltage differential (LVD) SCSI interface. This section provides general
information about the specifications for the tape drive’s Small Computer
System Interface (SCSI), including:
 SCSI cable requirements
 SCSI connector requirements
 Terminator requirements
Abort Task
Set
06h The initiator is clearing the present and any pending operation for that initiator.
When the tape drive accepts this message, it releases the bus into the Bus Free
phase.
Message
Reject
07h Either the initiator or the tape drive is indicating that the last message received was
inappropriate or not implemented.
No
Operation
08h The initiator informs the tape drive that it does not have a valid message to send
in response to the tape drive’s request for a message.
Message
Parity Error
09h The initiator informs the tape drive that one or more bytes in the last message it
received had a parity error.
Target Reset 0Ch The initiator instructs the tape drive to reset all of its current I/O operations. The
tape drive releases the SCSI bus into the Bus Free phase, with no operations
pending for any initiator, and performs a reset. (See page 24 for more information
about resetting the tape drive.)
Ignore Wide
Residue
23h The tape drive sends the Ignore Wide Residue message to indicate that the
number of valid bytes sent was less than the negotiated transfer width.
Identify 80h
or
C0h
This message is used to establish a physical path connection between the initiator
and the tape drive. It also indicates whether disconnect is supported and the LUN
for which the command is intended. The tape drive supports a LUN of 0.
Table 6-2 SCSI messages supported by the tape drive (continued)
Message
Hex
Code
Description
!
Important Although the tape drive’s High-density, 68-pin LVD SCSI
interface is compatible with both single-ended and narrow SCSI
buses, to avoid performance issues Tandberg Data does not
recommend using the tape drive on either of these buses.