Quantum DLTtape SDLT 220, User Manual

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APPENDIX A: Super DLTtape I Data Cartridge SDLT 220 and SDLT 320 Product Manual
A-12 March 2004 81-85002-01
Once a 320-formatted cartridge has become ready in an SDLT 220 drive, the drive
will report Density Code 00h (unknown format ) on any valid MODE SENSE
command.
If WRITE commands are given to a ready 320-formatted cartridge in an SDLT 220
drive, the WRITE commands will be honored. On this subsequent overwrite of the
320-formatted cartridge to 220 format, the drive will change the Density Code to
48h (220 format).
If calibration fails, the drive will report a persistent calibration error condition.
In most cases, REWIND commands will not return an error condition solely due to
format discrepancies when 320-formatted cartridge is ready in a 220 drive. On the
other hand, REWIND commands will report an error condition if mechanical or
servo related problems occur.
If a READ, SPACE, or LOCATE command is sent to an SDLT 220 drive
containing a 320-formatted cartridge, the drive will report a 05/30/02 Incompatible
Format (Cannot Read Medium) check condition. This includes Space Block or
Filemark in either a positive or negative direction. The only exception to the error
condition will be a LOCATE to block 0; a command of this nature is treated as a
REWIND command.
Please note that when a 320-formatted cartridge is overwritten in a 220 drive, all
320-formatted data on that cartridge is lost forever. This includes any future
attempt to space past the 220-formatted data into the old 320 formatted data in an
attempt to perform heroic data recovery.
N
OTE
: This discussion applies only to SDLT 220 drives
(firmware revision V45 and higher).