Counters - Keithley 6430 Instruction Manual

10-6 Triggering
MEASURE Action — During this phase of the SDM cycle, the measurement process takes
place. If the repeat filter is enabled, as shown in the blow-up drawing for Measure Action, the
instrument samples the specified number of reading conversions to yield a single filtered read-
ing (measurement). If using the moving filter or if the filter is disabled, only a single reading
conversion will yield a reading.

Counters

Programmable counters are used to repeat operations within the trigger model layers. For
example, if performing a 10-point sweep, the trigger counter would be set to 10. Operation will
stay in the Trigger Layer until the 10 source-delay-measure points of the sweep are performed.
If you wanted to repeat the sweep three times, the arm counter would be set to three. Three
10-point sweeps can then be performed for a total of 30 source-delay-measure actions.
The maximum buffer size for the SourceMeter is 2500 readings. The product of the two
counter values cannot exceed 2500. For example, if you set an arm count of two, the maximum
trigger count will be 1250 (2500 / 2 = 1250). However, you can set the arm count to INFINITE.
With an infinite arm count, the maximum trigger count is 2500.
NOTE
Output triggers
The SourceMeter can be programmed to output a trigger (via rear panel Trigger Link con-
nector) after various trigger model operations. An output trigger is used to trigger another
instrument to perform an operation. See Trigger link for more information.
Trigger Layer Output Triggers — After each action (Source, Delay, and Measure), the
SourceMeter can be programmed to send out an output trigger if Trigger Link is the selected
Trigger-In Source. For example, if the Trigger Out Event for Measure is ON, an output trigger
will be sent after the Measure action. When used with a scanner, an output trigger after each
measurement can signal the scanner to select the next channel in the scan.
Arm Layer Output Triggers — The SourceMeter can also be programmed to output a trig-
ger when operation enters the Trigger Layer, or after operation leaves the Trigger Layer and
enters back into the Arm Layer. This output trigger is typically sent to another instrument to
signal the end of a scan or sweep.
When a sweep is configured, the trigger model settings will not change until the
sweep is started. After the sweep is finished, the trigger model will reset back to the
previous settings.