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Synchronizing AI and Counter Tasks in DSA and M Series devices

Hello DAQ fellows, I am new in the Counter field, so it would be really helpful to have your comments and advices about my application.

I need to acquire simultaneouslythe following signals:

- AI Voltage signal with a DSA device (PXI 4461).
- AI voltage signal with a M Series device (PXI 6250).
- Periods between TTL pulses signal with one counter of the same M Series device. I want to use the counter as it is shown in the figure 7-8 attached below.

You can see my approach in the vi attached below (4461-6250ai-6250Ctr.vi). The 4461 is the master device.

For the synchronization between both AI tasks I am using the "SampleClockTimebase" of the master device as a source for the 6250. I am also using the "StartTrigger" signal from the master device to trigger the start of the AI acquisition in the 6250. As I understand, this configuration is OK.

Now come the second stage, which is to include the Ctr task to the acquisition process. I am creating the 3 tasks previously with another vi, the vi which creates the counter task (CreateTask6250Ctr.vi) is also attached. Now in the measurement vi (4461-6250ai-6250Ctr.vi), I use the "SampleClock" of the 6250-AI task in order to synchronize the AI with the Ctr task (I am not sure that this is the proper way to do this). Then I ask the "CounterTimebase.Source" in order to know which one is been used as SOURCE signal for the tick counting between the TTL pulses. Finally, I use the same "StartTrigger" signal from the master device to trigger the start of the Ctr task. In this way, when the AI task from the 4461 is started, it give the "StartTrigger" signal to the AI and Ctr tasks from the 6250 and the 3 start at the same time.

What do you think. am I right with my approach?
Is the Ctr task properly created to use the counter as in figure 7-8?
Are the three tasks properly synchronized?
Which other options do I have in order to synchronize the Ctr task with the other 2?

Thanking in advance,
Cristián
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Could I also use the PXI_Clk10 as a "ReferenceClock.Source" for the three tasks in order to synchronize them? I mean, instead of using the "SampleClock" of the AI task of the 6250 and the Ctr tasks of the same device. See the attachment to see what I mean.

Greetings,
Cristián
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Does anyone now? Can anyone help me understand this?

thank you
CJMV
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