Keithley 2001 Operator's Manual page 112

Front Panel Operation
group does not include channel# or time-stamp information.
In addition to these items, recalled data also includes
statistical information, such as minimum, maximum,
average, and standard deviation.
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CONFIG DATA STORE menu structure
Menu item
Burst-mode
Data-group
Full
Compact
Control
Fill-and-stop
Pretrigger
Percentage
Reading-count
Event
Continuous
Never
Clear-all
Count
Enter-count
Use-trigger-model
Feed
After-calc
Before-calc
The following paragraphs discuss configuration of the buffer
acquisition speed, data grouping, and buffer control, as well
as recalling buffered data. The CONFIG DATA STORE
menu structure is shown and summarized in
3.8.1 Burst mode
The burst data acquisition mode maximizes the reading rate
of the Model 2001. Burst mode consists of two distinct
phases:
• Acquiring raw readings (A/D counts).
• Post-processing the raw readings by applying calibra-
tion constants and storing the resulting readings in the
buffer.
In burst mode, the Model 2001 acquires 4.5-digit readings at
2000 readings/second. The post-processing takes about
2msec/reading. If any filter or math operations are enabled,
the post-processing time is longer. To make this reading rate
possible, certain trade-offs are made with the unit's
functionality, as described in the following paragraph.
3-80
Description
Acquire 4.5-digit readings at 2000 readings/sec and store in buffer.
Select data types to store in buffer.
Store reading, units, channel#, reading#, time-stamp, and status (overflow).
Store reading, units, reading#, and status (overflow).
Select type of buffer control.
Fill buffer with readings and stop.
Wait for pretrigger event; store before and after readings.
Enter percentage of stored readings before trigger.
Enter count of stored readings before trigger.
Select source for pretrigger event.
Store readings in buffer continuously.
Readings are not stored.
Clear all stored readings and buffer statistics.
Select buffer size.
Enter number of readings to store.
Use (finite) measure count from trigger model.
Select type of reading to store.
Store readings after percent or mX+b calculation.
Store readings before percent or mX+b calculation.
Table 3-30.
Configuring the unit for burst mode
Before burst mode can be enabled, the following changes
must be made to the present instrument configuration:
• Select a valid measurement function for the burst mode,
as listed in Table 3-31.
• Select a fixed range for the expected signal, or choose
autorange to let the instrument select a fixed range
when burst mode starts.
• Set the trigger event source in the measure layer to
immediate, external, trigger link, or timer.
• Disable any "multiple displays".
• Disable scanning.
If these changes are not made, a "Settings conflict" error or
similar message is displayed when you attempt to turn on
burst mode.
When burst mode is selected, the Model 2001 is
automatically configured for taking fast measurements. (The
instrument's previous settings are restored when burst mode
2001-900-01 Rev. K/ August 2010