Chapter 2. user interfaces, Operator control panel, Operator control panel philosophy – Dell TL2000 User Manual
Page 33: Chapter, User, Interfaces, Operator, Control, Panel, Philosophy
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Chapter
2.
User
Interfaces
This
library
has
two
user
interfaces.
v
Operator
Control
Panel
-
located
on
the
front
panel
of
the
library
v
Web
User
Interface
-
accessed
via
a
web
browser
Operator
Control
Panel
The
Operator
Control
Panel
operates
in
two
basic
modes.
v
User
Interaction
mode
-
This
mode
is
employed
when
a
user
is
pushing
buttons
on
the
Operator
Control
Panel.
v
System
Driven
mode
-
This
is
the
normal
mode
of
operation.
In
this
mode,
the
Operator
Control
Panel
displays
status
associated
with
the
actions
that
were
caused
from
commands
issued
via
the
drive’s
internal
(drive
to
library)
serial
interface.
When
an
Operator
Control
Panel
button
is
pressed
and
released,
the
Operator
Control
Panel
automatically
transitions
to
User
Interaction
mode.
User
Interaction
mode
will
continue
until
3
minutes
after
a
user
stops
pushing
buttons,
or
the
requested
accessor
action
stops
-
whichever
is
longer.
At
which
time,
the
Operator
Control
Panel
will
return
to
System
Driven
mode.
If
necessary,
the
Operator
Control
Panel
will
automatically
transition
to
the
System
Driven
mode.
When
this
occurs,
the
library
must
remember
what
the
user
was
doing
before
the
display
mode
changed.
Therefore
the
next
button
pressed
will
only
transition
the
Operator
Control
Panel
to
the
User
Interaction
mode
from
the
System
Driven
mode.
In
case
of
the
activated
user
security
feature,
the
User
Interaction
mode
is
restricted
to
Login
and
Monitor
menu
items,
until
a
user
logs
in
with
a
correct
password.
Operator
Control
Panel
Philosophy
Operator
Control
Panel
operation
must
obey
some
basic
rules.
These
rules
of
operation
constitute
a
philosophy.
v
Any
operational
conflict
between
commands
received
over
the
host
interface
or
the
Web
User
Interface
and
those
entered
via
the
Operator
Control
Panel
will
be
avoided
with
a
reservation
mechanism
on
a
first-come,
first-served
basis.
Any
reservation
by
the
Operator
Control
Panel
is
canceled
by
an
Operator
Control
Panel
logout
or
a
timeout,
which
cancels
the
User
Interaction
Mode.
v
Library
firmware
will
not
allow
a
user
to
select
an
impossible
request.
Those
situations
will
include,
but
are
not
limited
to:
–
Moving
a
cartridge
from
any
source
to
a
full
slot
–
Moving
a
cartridge
from
an
empty
slot
–
Loading
a
cartridge
from
any
source
to
a
full
drive
–
Unloading
a
cartridge
from
an
empty
drive
v
Any
error
detected
by
the
library
or
drive
controller
and
not
recoverable
through
predetermined
firmware
algorithms
will
be
considered
as
fatal.
An
error
code
will
be
displayed
on
the
Operator
Control
Panel
display
and
the
error
LED
will
2-1