Specifications
RIGOL Chapter 2 Command System
2-98 M300 Programming Guide
R?
Syntax
R? [<max_count>]
Description Read and erase the readings in the volatile memory (refer to Appendix D: Volatile memory).
The instrument starts reading from the oldest reading and up to <max_count> number of
readings can be read and erased. This command can be used to clear the reading memory
periodically to avoid data overflow (for example, during a scan with an infinite scan count).
Parameters
Name
Type
Range
Default
<max_count> Integer
Maximum number of
readings to be read and
erased from memory, from
1 to 10,0000.
If you omit <max_count>,
this command reads all the
readings in the volatile
memory.
Explanation This command is a special version of the DATA:REMove? command and provides faster
execution speed. You can read the radings in the memory at any time (even during a
scan) using this command.
For scan measurements using the multiplexer module, an error is generated if the
DMM module is disabled (refer to the
INSTrument:DMM command) or not installed in
the mainframe. The DMM module is not required for operations on the multifunction
module.
Each reading returned may or may not contain the measurement units, time stamp,
channel number and alarm status information, depending on the settings of the
FORMat Command Subsystem commands.
The instrument clears all the readings in the reading memory after a Factory Reset (the
*RST command), after an Instrument Preset (the SYSTem:PRESet command) or when
mainframe power is cycled (the power-on value is set to “Default”, refer to the
SYSTem:UTIlity:CONFigure:POWEron command).
Return
Format
The return value starts with #. For example,
#251+3.200441253E-03,+3.259494057E-03,+3.221523656E-03. The number “2”
following # denotes that the data length information 51 occupies 2 characters; the number
“51” denotes that there are 51-byte readings;
“+3.200441253E-03,+3.259494057E-03,+3.221523656E-03” are the 51-byte radings
(three readings).
Format explanation:
#251+1.366095803E-01,-4.475357308E-04,-3.702042950E-04
①
followed by 2 characters
②
followed by 51 bytes
③
3 readings(51 bytes)
Example R? 1
The query returns #216+3.200441253E-03.
Related
command
DATA:REMove?