SCSI Commands
Quantum DLT 7000 Tape System 5-65
5.9 MODE SELECT (6) / (10) COMMAND (15h / 55h)The MODE SELECT command (available in either 6- or 10-byte format) enables
the host to configure the tape drive. Implementing MODE SELECT and MODE
SENSE requires “handshaking” between the host and the drive. Before
configuring the drive, the host should issue a MODE SENSE command to the
drive to obtain a report of the current configuration and determine what
parameters are configurable. The host interprets this information and then may
issue MODE SELECT to set the drive to the host’s preferred configuration. The
Mode Parameter List described in Section 5.8 is passed from the initiator to the
drive during the command’s DATA OUT phase.
Information for the drive is carried on a number of pages, each of which serves
to set the tape drive’s operating parameters. The MODE SELECT pages
supported, and the sections of this manual that details each page, are:
Page Code Description Section
01h READ/WRITE Error Recovery Page 5.9.2
02h Disconnect / Reconnect Page 5.9.3
0Ah Control Mode Page 5.9.4
0Fh Data Compression Page 5.9.5
10h Device Configuration Page 5.9.6
11h Medium Partition Page 5.9.7
1Ch Tape Alert Page 5.9.8
3Eh EEPROM Vendor Unique Page 5.9.9
Except for mode page 3Eh, the tape drive always powers up with its default
configurations set. This is also true if the drive receives a BUS DEVICE RESET
message or a hard reset via the RST line on the SCSI bus.
The Command Descriptor Block is illustrated in Figure 5-32.
NOTE
For a list of changeable parameters within MODE SELECT, refer to
Sections 5.9.9 (EEPROM Vendor Unique Page 3Eh) and 5.9.10
(Changeable Parameters within MODE SELECT).