Keysight Technologies 3458A Guide D'utilisation page 257

– The multimeter's triggering hierarchy (trigger arm event, trigger event, and
– For direct-sampling, you should use the SINT memory/output format when the
– Related commands: DSDC, FUNC, LEVEL, LFILTER, SLOPE, NRDGS, PRESET
Example
The following program is an example of DC-coupled, direct-sampled digitizing.
The SWEEP command specifies an interval of 30 µs and 200 samples. Level
triggering is set for 250% of the 10 V range (250% of 10 V = 25 V). The samples
are sent to reading memory in DINT format. The samples are then sent to the
controller, converted, and printed. By deleting line 110, samples will be
transferred directly to the controller instead of using reading memory. However,
the controller and GPIB must be able to transfer samples at a rate of at least
134k-bytes/second or the multimeter will generate the TRIGGER TOO FAST error.
Refer to
10 OPTION BASE 1 !COMPUTER ARRAY NUMBERING STARTS AT 1
20 INTEGER Num_samples,I,J,K !CREATE INTEGER VARIABLES
30 Num_samples = 200 !200 SAMPLES
30 ASSIGN @Dvm TO 722 !DESIGNATE MULTIMETER ADDRESS
40 ASSIGN @Buffer TO BUFFER [4*Num_samplesl !ASSIGN BUFFER I/O PATH NAME
45 !SAMPLES, (4-BYTES/SAMPLE ∗ 200 SAMPLES = 800 BYTES)
50 ALLOCATE REAL Samp(1:Num_samples) !CREATE REAL ARRAY FOR SAMPLES
Keysight 3458A User's Guide
command). (The slew rate of the multimeter's amplifiers may be exceeded
when measuring a signal with a frequency >2 MHz and an amplitude >120% of
range; signals <120% of range with frequencies up to 12 MHz do not cause
slew rate errors.)
sample event) applies to direct-sampling. This means that these events must
occur in the proper order before direct-sampling begins. Refer to
more information on the triggering hierarchy. For direct-sampling, you can use
either the TlMER sample event and the NRDGS n,TIMER command, or the
SWEEP command (SWEEP is the simpler to program). The NRDGS and
SWEEP commands are interchangeable, the multimeter uses whichever
command was specified last. (When using the SWEEP command, the sample
event is automatically set to TIMER.)
peak value of the input signal is <120% of the specified range. Use the DINT
memory/output format when the input signal is ≥120% of the range. (SINT and
DINT are the formats used internally by the A/D converter; by using the correct
memory/output format, no format conversions are necessary.)
FAST, PRESET DIG, SSAC, SSDC, SSPARM?, SWEEP, TARM, TIMER, TRIG
High-speed transfer across GPIB
Command Reference
in Chapter 4 for more information.
6
Chapter 4 for
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