Fujitsu MAP3147 Scsi Logical Interface Specifications page 205

Despite the commands whose specified LBAs are overlapped, the IDD conducts reordering
operation. Therefore the INIT who specifies "1" in this field shall ensure Data Integrity itself.
The IDD disregards "1" in this field and operates as if "0" were specified.
When "F" is specified in this parameter, the IDD prohibits to order queued commands.
When other value is specified in this parameter, the IDD reports a CHECK CONDITION status
(ILLEGAL REQUEST [=5] / Invalid parameter in List [=26-00]).
e. QErr (queue error management)
This field controls processing of commands queued after a sense hold state is canceled when the
IDD is in the sense hold state.
Value
00b The IDD, when it has been in any one of various sense hold states, then that sense
hold state is cleared, continues executing the commands which are queued by
normal methods.
01b The IDD, when it has been in any one of various sense hold states, then that sense
hold state is cleared, clears the commands which are queued. At this time, the
IDD generates a UNIT ATTENTION condition (UNIT ATTENTION [=6] /
Command Cleared by Another Initiator [=2F-00]) for each of the INITs that issued
the commands which were cleared.
10b Reserved
11b The IDD, when it has been in any one of various sense hold states, then that sense
hold state is cleared, clears the commands which are queued by abnormal
terminated INIT.
The IDD is not supported "11b" specified in this field. If "11b" or "10b" is specified in this field,
the IDD reports a CHECK CONDITION status (ILLEGAL REQUEST [=5] / Invalid parameter
in list [=26-00]).
f. DQue (disable queuing)
This bit specifies whether the IDD will execute processing of tagged commands or not.
"1" : The IDD prohibits tagged queuing processing. The IDD clears queued commands and
generates a UNIT ATTENTION condition (Command cleared by another initiator [=2F-
00]) for each of the INITs that issued the commands which were cleared. After that, the
when a QUEUE TAG message is received, it is rejected with a MESSAGE REJECT
message and executed as an untagged command.
"0" : The IDD permits tagged queuing processing.
C141-E167
Description
4.1 Mode Parameters
4 - 29