Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications page 23

(5) Control byte
Bit 7
0
a. Link
Command link is specified by this bit is "1." Details of the operation of the command link are
described in Section 1.3.2.
b. Bit 7, 6 (vendor unique)
When 1 is specified in these bits, the command ends with a CHECK CONDITION status.
(6) Handling an illegal CDB
If there is an error in the contents of a description (specification) in the CDB, or if there is an error in the
specifications in parameters transferred from the INIT by CDB specifying, that command ends with a
CHECK CONDITION status. In the case of a command to change the data on the disk media, when
there is an error in the CDB's specifications, the disk media is not changed by that command. But when
there is an error in the parameters transferred in the DATA OUT phase, the contents of the disk media in
the range specified by the command may be changed. Also, even in cases where there is an error in the
CDB's specifications in a command accompanying the DATA OUT phase, the DATA OUT phase is
executed after the COMMAND phase is terminated, but those data are not used. For example, if there is
an error in the CDB specification of a WRITE command, the IDD executes the transfers several bytes of
data (the data length to be transferred is not specified), but those data are not written to the disk media.
Details are described in the individual command specifications in Chapter 3.
If there is an error in the CDB specification in a command which executes disconnect processing (shown
in Section 1.3.3), the disconnect processing may be executed after the COMMAND phase is terminated.
In this case, reconnect processing is executed afterward and the status (CHECK CONDITION) is
reported.
Note:
If a CDB with an undefined group code (group 3) is specified, the IDD requests transfer of 10 bytes
in the COMMAND phase. After that has been received, the status (CHECK CONDITION) is
reported.
C141-C010
6 5 4
0 0 0
3 2 1
0 0 0
1.1 Command Format
0
Link
1-5