Tandberg Data
Message System
6-3
Tandberg SLR Product Line SCSI Functional Specifications
MESSAGE REJECT
The Drive sends a MESSAGE REJECT message to the
Initiator if it receives a message other then the
messages listed in the message out table shown below
(table 6-2). The Drive also sends a MESSAGE REJECT
message to the Initiator if it receives a MESSAGE REJECT
message following phases other than a MESSAGE-IN phase.
RESTORE
POINTERS
This message will be sent by the Drive to the Initiator
before the Drive attempts a retransfer of Data or a
Status Byte.
SAVE DATA
POINTER
This message will be sent by the Drive to the Initiator
before sending the DISCONNECT message to inform the
Initiator that a pointer save operation is advised.
IGNORE WIDE
RESIDUE
This two-byte message will be sent by the Drive to the
Initiator to indicate that the number of valid data
bytes sent during the last REQ/ACK handshake of a DATA
IN phase is less than the negotiated transfer width. The
message will be sent immediately following the DATA IN
phase. The second byte of the message contains the
number of invalid data bytes transferred, and will be
set to 01h.
6.2.
Message Out
The Drive supports the Message-Out Bytes shown in the
table below:
Message Name
Input/Output
Hex Code
ABORT TASK SET
TARGET RESET
EXTENDED MESSAGE
IDENTIFY
INITIATOR DETECTED ERROR
MESSAGE PARITY ERROR
MESSAGE REJECT
NO OPERATION
O
O
I/O
I/O
O
O
I/O
O
06
0C
01
80+
05
09
07
08
Table 6-2: The Message-Out Set
ABORT TASK SET
Abort the current operation. The Drive goes to the BUS
FREE phase. No Status or ending Message will be sent
(see section 6.5 for details on the ABORT TASK SET
message handling).
TARGET RESET
Abort the current operation. The Drive goes to the BUS
FREE phase. No Status or ending Message will be sent.
Possible data in the data buffer will neither be
transferred to the Initiator nor written to the tape.
Possible pending error conditions will be cleared and
reservations are released. This message results in a
hard reset, ref. section 3.5.2.
EXTENDED
MESSAGE
This message is sent by the Initiator to the Drive as
the first byte of a multiple byte message. See Section
6.3 for a description of the extended messages.
