Example LPT function sequence: pulse-measure synchronization
The following LPT function sequence uses the software trigger to initiate a 3-pulse burst for
CHANNEL 1. The three output pulses trigger the scope to perform three measurements. It assumes
the scope is configured to trigger on leading edge triggers from the pulse generator.
// Stop pulse generator output:
pulse_halt(VPU1);
// Turn off trigger output:
pulse_trig_output(VPU1, 0);
// Set the output trigger polarity to positive:
pulse_trig_polarity(VPU1, 1);
// Select Software trigger source:
pulse_trig_source(VPU1, 0);
// Set channel 1 for a burst count of 3:
pulse_burst_count(VPU1, 1, 3);
// Turn channel 1 on:
pulse_output(VPU1, 1, 1);
// Select the Trig Burst trigger mode and trigger start of burst output. Each pulse will
trigger the
// scope to perform a measurement.
pulse_trig(VPU1, 2);
Measurement types
There are two types of pulse measurements: Spot mean and waveform. The pulse_meas_sm
function is used to configure Spot mean measurements (on page 4-24) and the pulse_meas_wfm
function is used to configure Waveform measurements (on page 4-25).
The Model 4225-PMU makes the following types of pulse measurements:
• Spot mean discrete
• Spot mean average
• Waveform discrete
• Waveform average
Use the following pulse generator functions to configure pulse measurements:
• Use the pulse_meas_sm function to configure spot mean measurements; select the data
acquisition type, set the readings to be returned, enable or disable time stamp, and set LLEC.
See Spot mean measurements (on page 4-24) for details.
• Use the pulse_meas_wfm function to configure waveform measurements; select the data
acquisition type, set the readings to be returned, enable or disable time stamp, and set LLEC.
See Waveform measurements (on page 4-25) for details.
• Use the pulse_meas_timing function to set measurement timing. For spot mean
measurements, portions of the amplitude and base levels are specified for sampling. For pre-data
and post-data waveform measurements, a percentage of the entire pulse duration is specified.
See Measurement timing (on page 4-27) for details on pulse measurement timing.