HP 8753D - Non-Volatile Memory

Non-V
olatile
Memory
This
is
CMOS
read/write
memory
that
is
protected
by
a
battery to
provide storage
of data
when
line
power
to
the
instrument
is
turned
o.
With this
battery protection,
data can
be retained
in
memory
for

250
days
at
70

C
and
for

10
years
at
25

C
(characteristically).
Non-volatile
memory
consists
of
a
block
of
user-allocated
memory and
a block
of xed
memory.
The
user-allocated
memory
is
available
for
you
to
save
the
following data:
instrument
states
measurement
calibration
data
power
meter
calibration
data
user
calibration
kit
denitions
memory
traces
user
preset
Note
Even
though
calibration
data
is
stored
in
non-volatile
memory
,
if
the
associated
instrument
state
is
not
saved,
you
will
not
be
able
to
retrieve
the
calibration
data
after
a
power
cycle
.
The
xed memory
is
used
to
store
the
following
data
(you
cannot
change
where
this
data
is
stored
and it
does not
aect
your
memory
availability
for
storing
user-allocated
data):
HP-IB
addresses
copy
conguration
(printer
and
plotter
type
,
port,
baud
rate
,
handshake)
power
meter
type
(HP
436/438)
display
colors
sequence
titles
sixth
sequence
power
sensor
calibration
factors
and
loss
tables
user-dened
calibration
kits
system
Z0
factory
preset
HP-IB
conguration
display
intensity
default
The
maximum
number
of
instrument states
, calibrations
, and
memory
traces
that
can
reside
in
non-volatile
memory
at
any one
time is
limited to
31 instrument
states
,
128
calibrations
(4
per
instrument
state
,
including the
present instrument
state), and
64 memory
traces
(2
per
instrument state
, including
the present
instrument
state).
In
addition,
the
number
of
instrument
states and
associated
calibrations
and
memory
traces
are
limited by the available memory
.T
o
display the amount of unused memory on the analyzer
,
press 4
SAVE/RECALL
5 . (Be sure you have selected
N
NNN
NNNNNNNNNNNNNNNNNNNNNNNNN
NNNNNNNNNNNNNNNNNN
INTERNAL MEMORY
as your disk type
.) In the
upper right-hand portion of the display
, the value displayed as
Bytes free:
is the unused
non-volatile memory
. When you save to the internal memory
, you will see the number of bytes
free decrease
. When you
delete les
, the number of bytes free increases
. There is a maximum
of 512 kBytes available
.
If you have deleted registers since the
last time the instrument was preset, the bytes available
for you to use may be less than the actual \bytes free" that is displayed. Deleting registers
to increase the available memory will work in cases where the registers being deleted and
the registers needing to be added are of the same standard size (such as instrument states not
having calibrations associated with them). In certain other cases, however, you may have
to press 4
PRESET
5 after deleting registers so that the \bytes free" value equals the available
memory value. During a preset, the analyzer runs a memory packer that de-fragments the free
memory into one contiguous block.
12-2 Preset State and Memory Allocation