84
Chapter 8 SCSI Commands
8.6. MODE SENSE(6) Command (1Ah)
The MODE SENSE(6) command allows the autoloader return held parameters
to the host. This command is used in parallel with MODE SELECT(6).
Table 8.6.1 : MODE SENSE(6) command
When the Disable Block Descriptors (DBD) bit is 0, the MODE SENSE data
returned by the autoloader is transferred with an appended Mode Parameter
Block Descriptor. When the DBD bit is 1, the MODE SENSE data returned by
the autoloader does not have an appended Mode Parameter Block Descriptor.
8.6.1. Page Control
The Page Control (PC) field specifies the type of Mode Parameter of the
returned Mode Page. The Page Control field is defined in Table 8.6.1.1.
Table 8.6.1.1 : Page control field
Note
The Page Control field only affects the Mode Parameters within the Mode Page.
The PS bit, Page Code, and Page Length field do not return the current value.
For the Mode Parameter Header and Mode Parameter Block Descriptor, the
current values are returned.
8.6.1.1. Current values
When the PC field is 00b, the autoloader returns current values as Mode
Parameters. The returned current values are as follows.
a) Current values of the Mode Parameters established by the last successful
MODE SELECT command.
b) If there was no successful MODE SELECT command since the last two
power on, hard reset, or BUS DEVICE RESET message, the current values
are the Mode Parameter values held internally by the autoloader.
c) If a value held internally by the autoloader (value in non-volatile memory)
is invalid, the current values are the autoloader default.
Bit
Byte
7
6
5
4
3
2
1
0
0
Operation code (1Ah)
1
Logical unit number(0h)
Reserved
DBD
Reserved(0h)
2
PC
Page code
3
Reserved(0h)
4
Allocation length
5
Control(0h)
Code
Type of parameter
Sub clause
00b
Current values
01b
Changeable values
10b
Default values
11b
Saved values
