Scpi Programming - Keithley 6514 Instruction Manual

8-4 Buffer

SCPI programming

Commands associated with buffer operation are listed in Table 8-1. The TRACe commands
are used to store and recall readings in the buffer. The FORMat:ELEMents command is used to
specify which data elements to include in the response message for TRACe:DATA? (which is
the command to read the buffer). The CALCulate3 commands are used to obtain statistics from
the buffer data.
NOTE
Table 8-1
SCPI commands — buffer
Commands
:TRACe
:CLEar
:FREE?
:POINts <n>
:ACTual?
:FEED <name>
:CONTrol <name>
:TSTamp
:FORMat <name>
:DATA?
:FORMat
:ELEMents <list>
:CALCulate3
:FORMat <name>
:DATA?
Note: SYSTem:PRESet and *RST have no effect on :TRACe commands. The listed defaults are power-on defaults.
A) TRACe:FREE?
Two values, separated by commas, are returned. The first value indicates how many bytes of
memory are available, and the second value indicates how many bytes are reserved to store
readings.
The Model 6514 uses IEEE-754 floating point format for statistics calculations.
Description
TRACe Subsystem:
Clear readings from buffer.
Query bytes available and bytes in use.
Specify number of readings to store; 1 to 2500.
Returns number of readings actually stored in buffer.
Select source of readings; SENSe[1], CALCulate[1] or
CALCulate2.
Select buffer control mode; NEVer or NEXT.
Timestamp:
Select timestamp format; ABSolute or DELTa.
Read all readings in buffer.
FORMat Subsystem:
Specify data elements for :TRACe:DATA? response
message; READing, TIME and STATus.
CALCulate3 Subsystem:
Select buffer statistic; MINimum, MAXimum, MEAN,
SDEViation or PKPK.
Read the selected buffer statistic.
Default Ref
See Note
A
100
SENS1 B
NEV C
ABS D
E
Sec
16
All 3 F
MEAN G
H