Counters - Keithley 6430 Instruction Manual

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 (TRIGger:
COUNt 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
(ARM:COUNt 3). 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 finite
values of the two counters 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 (INF). With an infinite arm count, the maximum trigger count is 2500.
NOTE
With front panel operation only, when a sweep is configured, the trigger model set-
tings will not change until the sweep is started. After the sweep is finished, the trig-
ger model will reset back to the previous settings.
Output triggers
The SourceMeter can be programmed to output a trigger (via rear panel Trigger Link
connector) after various trigger model operations. An output trigger is used to trigger another
instrument to perform an operation. See Trigger link earlier in this section for more
information.
Trigger Layer Output Triggers — The SourceMeter can be programmed to output a trigger
after each action of the SDM cycle (Source, Delay, and Measure). Output triggers are con-
trolled with the TRIGger:OUTPut command.
For example, to output a trigger after the Measure Action, the following command must be
sent:
TRIGger:OUTPut SENSe
The above command disables output triggers for the Source and Delay Actions since their
parameter names (SOURce and DELay) are not included in the parameter list.
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 — As shown in Figure 10-9, the SourceMeter can be pro-
grammed to output a trigger when operation leaves the Arm Layer and enters the Trigger Layer,
or after operation leaves the Trigger Layer and enters back into the Arm Layer. This output trig-
ger is typically sent to another instrument to signal the end of a scan or sweep. The ARM:OUT-
Put command is used to control these output triggers. The TENTer parameter enables the
trigger on entering the Trigger Layer, the TEXit parameter enables the trigger on exiting the
Trigger Layer, and the NONE parameter disables both output triggers.
Triggering 10-21