Section 3: Functions and features
Model 2657A High Power System SourceMeter® Instrument Reference Manual
3-10
2657A-901-01 Rev. B/December 2012
Displaying other buffer readings and statistics
To display other readings and statistics in the reading buffer:
1. While still in the buffer recall mode:
•
If viewing the data stored in the buffer, turn the navigation wheel
to increment and decrement the
selected digit of the location number by one. Press the navigation wheel
and then turn it or use the
CURSOR
keys to move to the next digit that the navigation wheel
will change.
•
If viewing the statistics stored in the buffer, turn the navigation wheel
or use the
CURSOR
keys to
scroll between MEAN, STD DEV, SAMPLE SIZE, MINIMUM, MAXIMUM, and PK-PK.
2. To exit from the reading buffer recall mode, press the
EXIT (LOCAL)
key.
Remote reading buffer programming
You can get readings by making overlapped or sequential measurements. Routines that make
single-point measurements can be configured to make multiple measurements where one would
ordinarily be made.
The measured value is not the only component of a reading. The measurement status (for example,
“In Compliance” or “Overranged”) is also an element of data associated with a particular reading.
All routines that return measurements can store the measurements in the reading buffers.
Overlapped measurements always return readings in a reading buffer. Non-overlapped measurement
functions can return single-point measurement values or store multiple values in a reading buffer.
A reading buffer is based on a Lua table. The measurements are accessed by ordinary array
accesses. If
rb
is a reading buffer, the first measurement is accessed as
rb[1]
and the 9th
measurement as
rb[9]
. The additional information in the table is accessed as additional members of
the table.
The load, save, and write operations for reading buffers function differently in the remote state. From
a remote command interface, you can extract data from reading buffers as the instrument acquires
the data.
Dedicated reading buffer designations
The source-measure unit (SMU) contains two dedicated reading buffers:
•
smua.nvbuffer1
(buffer 1)
•
smua.nvbuffer2
(buffer 2)
To access a reading buffer, include the name of the SMU in the attribute. For example, the following
command would store readings from channel A into buffer 1:
smua.measure.overlappedi(smua.nvbuffer1)
Summary of Contents for 2657A
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