HP C2488A Technical Reference Manual page 71

Mode Select, Mode Sense
Mode Select, Mode Sense
The MODE SELECT command provides a means for the Initiator to specify media, logical
unit, or peripheral device parameters to the Target.
The MODE SENSE command provides a means for a Target to report its media, logical unit,
or peripheral device parameters to the Initiator. It is a complementary command to the
MODE SELECT command.
Mode Select Command Description
If a MODE SELECT modifies operating parameters that are common to other Initiators,
the Target will report CHECK CONDITION status and UNIT ATTENTION Sense Key
with Additional Sense Code of MODIFIED PARAMETERS when next accessed by other
Initiators but not by the Initiator issuing the MODE SELECT command. This rule does
NOT override the normal first access rule for each Initiator, nor does it override the normal
rules for INQUIRY and REQUEST SENSE.
Byte
00
01
02-03
04
05
Byte
00
01
02-06
07-08
09
Note
DRAFT
1/18/93 09:58
Mode Select (6-Byte) Command Descriptor Block (COB)
Bit
7
I
6
I
5
J
4
I
.3
J
2
1
1
I
0
Opcode = ISH
Logical Unit Number
I
PF
I
Reserved
I
SP
(MSB=02)
Reserved
(LSB=03)
Parameter List Length
Control Byte
Mode Select (10-Byte) Command Descriptor Block (COB)
Bit
7
I
6
I
5
I
4
I
3
I
2
I
1
I
0
Opcode = 5SH
Logical Unit Number
I
PF
I
Reserved
I
SP
(MSB=02) Reserved
(LSB=06)
(MSB=07) Parameter List Length (LSB=08)
Control Byte
Bit 7 of the Mode Select control byte will enable (1) or disable (0) the Write
Protect mode. The WP bit in the Mode Sense parameter list header reports
the Write Protect status: 1
= enabled, 0 = disabled.
SCSI Command Descriptions A-15