Reference Guide

Chapter 4 SCSI Commands
MODE SENSE (6) / (10) Command (1Ah / 5Ah)
DLT-S4 Interface Reference Guide 161
Table 90 MODE SENSE Data
Header — Field Descriptions
Field Description
Mode Data Length Specifies the length in bytes of the
MODE SENSE data that is available to be
transferred.
Note that the Mode Data Length does not include its own length.
Medium Type The drive checks the media type, which can be one of the following:
Type Description
00h Unknown or not present
81h Cleaning tape
86h Super DLTtape I
1
87h Super DLTtape II
1
, Super DLTtape II WORM
1
91h DLTtape S4, DLTtape S4 WORM
WP Write Protect. When set to 0, indicates that the tape is write-enabled. When set to 1,
indicates that the tape is write-protected.
Buffered Mode When set to 0, the drive does not report a
GOOD status on WRITE commands until it
actually writes the data blocks to tape.
When set to 1, the drive reports
GOOD status on WRITE commands as soon as the
data block has been transferred to the buffer. This is the default configuration of the
drive. Note that if Buffered Mode is not used, the drive suffers a degradation of
performance and capacity.
Speed Always set to 0, indicating the default speed.
Block Descriptor
Length
Specifies the length in bytes of all of the block descriptors. If the DBD bit in the CDB
is set to 0, this value is 8, indicating one Block Descriptor was sent. If the DBD bit in
the CDB is set to 1, this value is 0, indicating no Block Descriptors were sent.
1. When these cartridges are mounted in the drive, the MODE SENSE information reports the Media Type and the
correct Density Code as detected on the tape and sets the Write Protect (WP) bit in the MODE SENSE header to
1. Any command that attempts to write to the medium (WRITE, WRITE FILEMARKS, ERASE) returns CHECK
CONDITION status with Sense Key set to DATA PROTECT (7) and the Additional Sense Code or Additional
Sense Code Qualifier set to CANNOT WRITE MEDIUM - INCOMPATIBLE FORMAT (30h/05h). The drive does
not update the medium.