User's Guide

Commands: Mode Sense (1Ah) Page 89
MODE SENSE (1Ah)
The MODE SENSE command allows the host to determine various drive device
parameters. These parameters are sent from the drive to the host as data formatted
in a parameter list. This command is a complementary command to the MODE
SELECT command.
The drive terminates execution of the MODE SENSE command as follows:
• When the number of bytes specified in the Allocation Length field have been
sent to the host, or
• When all available MODE SENSE data has been sent to the host.
During execution of this command, the drive does not disconnect from the host.
Also, this command performs no media access.
If a MODE SELECT command has not been performed since power-on/SCSI Reset,
the default mode parameters are in effect.
All MODE SELECT parameters may be rounded up or down, as appropriate. A
MODE SENSE command may be issued after a MODE SELECT command to
determine which parameters have been rounded.
MODE SENSE Command Descriptor Block
The following table shows the layout of the CDB.
Byte
Bits
7 6 5 4 3 2 1 0
0 0 0 0 1 1 0 1 0
1 0 0 0 0 DBD 0 0 0
2 PC | Page Code
3 0 0 0 0 0 0 0 0
4 Allocation Length
5 vendor unique* 0 0 0 0 Flag Link
* This vendor-unique field is reserved and must be set to zero.