Error Conditions For All Commands - Tandberg Data SLR7-140 PROGRAMMER Manual

Bus Parity Error
BUSY Status
Invalid Command
Operation Code
Message Parity
Error Message
Overlapped
Commands
Reservation
Conflict
Tandberg Data
7.2.

Error Conditions for All Commands

When an Initiator accesses the Drive, there are a number
of error conditions that may occur regardless of the
command the Initiator attempts to issue. This section
summarizes all such error conditions. See the separate
sections for details.
conditions, please see the section on General Exception
Handling for the actual command.
Every command may be terminated with CHECK CONDITION
status if a bus parity error is detected in the Command
Descriptor Block, data out or message out. See Section
7.5. for details.
The Drive is busy executing a command.
The command can be accepted, but it can not be executed
yet since the Drive is busy.
Three different BUSY situations may occur:
1) The drive is already executing a command from another
initiator and the new command can't be executed in
parallel.
2) The Drive is executing an Immediate-type command
(from any initiator) and the BSYI-option is turned on
(refer the Miscellaneous Parameters Page in the MODE
SELECT command). This condition will prevail until
the Immediate-type command has completed its
execution (or the BSYI-option is turned off).
3) The drive is occupied by a drive-initiated
preparation activity (as e.g. Autoload) and the BSYA-
option is turned on (refer the Miscellaneous
Parameters Page in the MODE SELECT command). This
condition will prevail until the drive-initiated
activity has completed (or the BSYA-option is turned
off).
If the Command Operation Code (byte 0 of the CDB) is not
in the range of supported Command Operation Codes, the
command will then be terminated with CHECK CONDITION
Status. The Error Code will be set to I
.
OPERATION CODE
Every command may be terminated if a MESSAGE PARITY
ERROR message is received. The Error Code will be set to
SCSI .
PARITY ERROR
See section 7.5. for details.
If an Initiator issues a new command while it still has
a command under
command is aborted and the new command is terminated
with CHECK CONDITION. The Error Code will be set to
O
VERLAPPED COMMANDS ATTEMPTED
See section 4.6 for details.
Every command except INQUIRY, REQUEST SENSE and RELEASE
will be terminated with RESERVATION CONFLICT status if
the Drive has been reserved for another Initiator.
See the RESERVE and RELEASE commands for details.
7-5 Tandberg SLR Product Line SCSI Functional Specifications
For command
execution by the
.
General Exception Handling
specific error
NVALID COMMAND
Drive, the first