Qualstar 34XX Series, Руководство пользователя

Страница: 40 / 107

500300 Rev. U
Operating Instructions 3-11
In this mode, you can change the write and read densities by the Density switch, the
interface, or by loading a tape of a different density.
3.6.2.3 Read Mode
In the Read mode, the drive reads the ID burst at the end of each load sequence and
changes the read density to match it. The write density will remain unchanged. If
the drive has just been powered up, the write density assumes the value of the
INITIAL DEN parameter.
•
The drive performs all read commands from BOT at the indicated read density
and changes the write density to match it. Thus, if a tape is loaded, read,
returned to BOT and then a write command is received, the original density of
the tape will be preserved.
• The drive performs all write commands from BOT at the indicated write density
and changes the read density to match it.
In this mode, you can change the write density by the Density switch, the interface
or by loading a tape of a different density and reading before writing on it.
3.6.2.4 Dual Mode
In the Dual mode, the drive reads the ID burst at the end of each load sequence and
changes the read density to match it. The write density will remain unchanged. If
the drive has just been powered up, the write density assumes the value of the
INITIAL DEN parameter.
•
The drive performs all read commands from BOT at the indicated read density
and changes the operating density to match. If blocks are then overwritten or
appended, they will be written at the original density of that tape.
•
The drive performs all write commands from BOT at the indicated write density
and changes the operating density to match.
•
Each time a tape reaches BOT (via any interface command, an offline rewind, or
a load sequence), the write density returns to its original value.
In this mode, the write density can only be changed by the Density switch or the
interface. Loading a tape of a different density and reading will not change the write
density.
3.6.2.5 Initial Mode
In the Initial mode, the drive reads the ID burst at the end of each load sequence
and changes the read density to match it. The write density assumes the value of the
INITIAL DEN parameter.
•
The drive performs all read commands from BOT at the indicated read density
and changes the operating density to match. If blocks are then overwritten or
appended, they will be written at the original density of that tape.