R? [<
max_readings
>]
Reads and erases all measurements from reading memory up to the specified <
max_readings
>. The meas-
urements are read and erased from the reading memory starting with the oldest measurement first.
Parameter
Typical Return
1 to 2,000,000 (readings)
Default is all readings in memory.
(none)
Read and remove the three oldest readings:
R? 3
Typical Response: #247-4.98748741E-01,-4.35163427E-01,-7.41859188E-01
The "#2" means that the next 2 digits indicate how many characters are in the returned memory string.
These two digits are the "47" after the "#2". Therefore, the remainder of the string is 47 digits long:
-4.98748741E-01,-4.35163427E-01,-7.41859188E-01
l
The
and
queries can be used during a long series of readings to periodically remove
readings from memory that would normally cause the reading memory to overflow.
does not wait
for all readings to complete. It sends the readings that are complete at the time the instrument
receives the command. Use
or
if you want the instrument to wait until all readings are
complete before sending readings.
l
If you do not specify a value for <
max_readings
>, all measurements are read and erased.
l
No error is generated if the reading memory contains less readings than requested. In this case, all
available readings in memory are read and deleted.
l
The number of readings returned may be less than that requested depending on the amount of read-
ing memory in your instrument. You can store up to 1,000 measurements in the reading memory of
the 34460A, 10,000 measurements on the 34461A, 50,000 measurements on the 34465A/70A
(
without
the MEM option), or 2,000,000 measurements on the 34465A/70A (
with
the MEM option). If
reading memory overflows, new measurements overwrite the oldest measurements stored; the most
recent measurements are always preserved. No error is generated, but the Reading Mem Ovfl bit (bit
14) is set in the Questionable Data Register's condition register (see
).
l
The instrument clears all measurements from reading memory when the measurement configuration
changes, or when any of these commands are executed:
,
,
.
Keysight True
volt
Series Operating and Service Guide
205
SCPI Programming Reference