Keithley 2461 Reference Manual page 182

Model 2461 Interactive SourceMeter® Instrument Reference Manual
5. Select the style. The Initial Capacity dialog box is displayed.
6. Enter the number of readings and select OK.
Using SCPI commands to set the buffer style:
To create a compact reading buffer named testData with a capacity of 300 readings, send the
following command:
TRACe:POINts 300, "testData", COMPact
Using TSP commands to set the buffer style:
To create a compact reading buffer named testData with a capacity of 300 readings, send the
following command:
testData = buffer.make(300, buffer.STYLE_COMPACT)
Setting the fill mode
The fill mode setting for the reading buffer controls how the incoming data is managed as the buffer
fills. You can set the read buffer to:
•
Fill once: The buffer stops accepting data once it fills to capacity. When the buffer reaches
capacity, no more readings are made and event code 4915, "Attempting to store past capacity of
reading buffer" is displayed.
•
Fill continuously: Data fills the buffer normally until the end of the buffer is reached. When the
end is reached, the data returns to the beginning of the buffer and overwrites the oldest reading.
This is a traditional circular buffer. In this case, the buffer never technically fills.
The following topics describe how to set the reading buffer fill mode.
When readings are made using a high sample rate and stored into a continuous reading buffer with a
capacity of less than 1000 readings, the instrument may not be able to fully process the incoming
data before it is overwritten with new data. This can result in gaps in graph traces and the loss of
statistics and histogram information. To prevent these problems, increase the buffer capacity or
reduce the sample rate.
2461-901-01 A/November 2015
Figure 93: Select the buffer style
Section 3: Functions and features
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