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Using the DAS-1700 Series with DriverLINX
Keithley DAS-1700 Series
Synchronizing an Analog Output Task with an Analog Input
Task
On the DAS-1700 Series, DriverLINX can synchronize an analog output task with an
analog input task. The analog output task uses the same timing event as the input
task.
To synchronize an analog output (AO) task with an analog input (AI) task:
1.
Set up the AI service request.
2.
Set up the AO service request using an identical timing event as the AI
task, except with set the Period to zero. Both the AI and AO timing
event must use Counter/Timer channel 0.
3.
Submit the AO service request. The hardware runs the AO task only
while the AI task is running.
4.
Submit the AI service request to start both tasks.
Although both tasks share the same clock source, they are otherwise logically
independent of each other. Your application must manage and respond to each task
separately. If the AI task terminates before the AO task, the AO task will still be
logically active, but the clock stop sending timing pulses to the AO task until the next
AI task starts. If you want to terminate the AO task when the AI task stops, either set
up both service requests with equal buffer sizes and Stop Events, or issue a Stop
operation request for the AO task.
Analog Output Start Events
Start Events specify when the DAS-1700 hardware starts acquiring analog output
data.
The DAS-1700 Series supports the following Start Events:
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None—Use this event when the DriverLINX operation does not require
a Start Event.
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Command—DriverLINX starts the task on software command, i.e., as
soon as DriverLINX finishes programming the DAS-1700 hardware for
the task.
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Digital—The DAS-1700 starts acquiring analog output samples when
the hardware detects the digital Logical Channel output satisfies the
condition specified in the Start Event.
None or Null Start Event
The Null Event specifies that the task does not need a Start Event to begin the task.
Command Start Event
The Command Event starts data acquisition as soon as DriverLINX has completed
programming the data-acquisition hardware with the task parameters.
Digital Start Event (Post-Triggering)
The DAS-1700 can write analog output samples after the hardware detects a digital
trigger condition. Use post-triggering when you want to synchronize the start of data
acquisition with an external signal.
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