Keithley System SourceMeter 2601B, Reference Manual

Page: 149 / 864

Section 3: Functions and features Series 2600B System SourceMeter® Instrument Reference Manual
3-14 2600BS-901-01 Rev. B / May 2013
Buffer read-only attributes
The following table contains buffer read-only attributes.
Buffer read-only attributes: Read-only attributes used to access buffer parameters
Storage attribute Description
basetimestamp The timestamp of when the reading at
rb[1]
was stored, in seconds from
midnight January 1, 1970 GMT. See Time and date values (on page 7-3) for
additional details.
capacity
The total number of readings that can be stored in the reading buffer.
n The number of readings in the reading buffer.
next
This attribute indicates where the next element that will be added to the reading
buffer will be stored.
Buffer storage control programming examples
The programming examples below illustrate the use of buffer storage control attributes.
Buffer control programming examples:
Command Description
smua.nvbuffer1.collectsourcevalues = 1
Enable source value storage.
smua.nvbuffer1.appendmode = 1
Enable buffer append mode.
smua.nvbuffer1.collecttimestamps = 0 Disable timestamp storage.
smua.nvbuffer1.timestampresolution =
0.001
Set timestamp resolution to 0.001024 s.
smua.nvbuffer1.fillcount = 50 Set 50 as the number of readings the
buffer will take before restarting at index
1.
smua.nvbuffer1.fillmode = 0
Set the reading buffer to fill once (do
not overwrite old data).
Buffer read-only attribute programming examples
The follow programming examples illustrate use of buffer read-only attributes.
Buffer read-only attribute programming examples:
Command Description
number = smua.nvbuffer1.n Request the number of readings in the
buffer.
buffer_size = smua.nvbuffer1.capacity Request buffer size.