6-8 Buffer and Sweeps Model 6487 Reference Manual
Programming example
The following program fragment stores 20 readings into the buffer and then calculates the
mean average on the buffer readings:
' Select data elements:
*RST ' Return 6487 to RST defaults.
FORM:ELEM READ,TIME ' Select reading and timestamp.
' Store and Recall Readings:
TRIG:COUN 20 ' Set trigger model to take 20 readings.
TRAC:POIN 20 ' Set buffer size to 20.
TRAC:FEED SENS ' Store raw input readings.
TRAC:FEED:CONT NEXT ' Start storing readings.
SYST:ZCH OFF ' Disable zero check.
INIT ' Trigger readings setup to SRQ on
' buffer full.
TRAC:DATA? ' Request all stored readings.
' Acquire Mean Statistic for Buffer Readings:
CALC3:FORM MEAN ' Select mean statistic.
CALC3:DATA? ' Request mean statistic.
Voltage sweeps
The Model 6487 voltage source can be used to generate voltage sweeps from a start volt-
age to a stop voltage at discrete step voltages. The Model 6487 stores readings in the
buffer for later recall, one set of readings per voltage step.
Overview
As shown in Figure 6-2, a voltage sweep is performed from a start voltage to a step voltage
at discrete step voltages. At each step voltage:
• The source voltage is set to the new value.
• The unit waits for the programmed delay period.
• The reading is taken and stored in the buffer for later recall.
Note that sweeps can be positive-going or negative-going by programming the start and
stop voltages accordingly, but the programmed step voltage is always positive.