Quantum DLT 4000 Product Manual page 158

Firmware Update (From Tape)
g. When the drive code update is complete, the drive resets, and
goes through Power-On Self-Test (POST). The process waits
until the tape is reloaded at beginning of tape (BOT).
h. If the firmware image is valid, the controller's flash EEPROM
memory is automatically updated with the new firmware
image.
i. Whether the firmware update is successful, the subsystem
resets itself. A full, extended scan of the loader takes place.
The scan goes quickly if the firmware update cartridge was
the only tape cartridge in the magazine. If six other cartridges
are present, the scan takes an extra minute or more.
7.4.3.1 Interpreting the Results (DLT4700) Code Update)
Two possible results can occur:
The firmware update cartridge is unloaded: this means a successful
update.
On the DLT4000 drive, the cartridge is unloaded from the drive and
into the magazine slot from which it came. If another cartridge is in
the magazine, that next cartridge loads into the drive.
The firmware update cartridge is NOT unloaded: this means the
update was unsuccessful.
The subsystem should still be usable, but this depends on why the update failed.
Reasons for failure could be:
1. Power failure
2. Bad image on the tape
3. Broken Flash EEPROMs
7-16 DLT4000/DLT4500/DLT4700 Cartridge Tape Subsystem