Remote Reading Buffer Programming - Keithley 2601B Reference Manual

Series 2600B System SourceMeter® Instrument Reference Manual
Timestamp
If the timestamp is enabled, the first source-measure reading stored in the buffer (#0000001) is
timestamped at 0.000 seconds. Subsequent readings are timestamped relative to when the first
measurement was made. The interval between readings depends on the reading rate.
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
selected digit of the location number by one. Press the navigation wheel
CURSOR keys to move to the next digit that the navigation wheel
•
If viewing the statistics stored in the buffer, turn the navigation wheel
scroll between MEAN, STD DEV, SAMPLE SIZE, MINIMUM, MAXIMUM, and PK-PK.
1. 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
Each source-measure unit (SMU) contains two dedicated reading buffers:
•
smuX.nvbuffer1 (buffer 1)*
•
smuX.nvbuffer2 (buffer 2)*
* smuX: For Models 2601B, 2611B, and 2635B, this value is smua (SMU Channel A); for Models
2602B, 2604B, 2612B, 2614B, 2634B, and 2636B, this value can be smua (for SMU Channel A) or
smub (for SMU Channel B).
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)
2600BS-901-01 Rev. B / May 2013
Section 3: Functions and features
to increment and decrement the
and then turn it or use the
will change.
or use the CURSOR keys to
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