Trigger channels cDAQ 9239

[EdoardoA]

Hi all,

I am curious to know if it would be somehow possible to accomplish the following task:

I have a cDAQ-9174 module with a NI9239 voltage reader. I am wiring 2 of the 4 channel available in the following way: the first channel is getting input from the TTL signal from a laser source. the second channel is recording the current from a generic sample (ex. a photodiode (PD)).

My question: is it somehow possible to trigger the second channel (PD, when to acquire the signal) by getting the "trigger" signal from the first channel (TTL signal)?

So I can acquire only when the laser pulse is actively hitting the PD or a generic sample.

Thanks

E

[ZYOng · Accepted solution]

Unfortunately, NI-9239 does not support analog triggers and cDAQ-9174 does not have any PFI ports for triggering. You would need a digital module. Reference: Setting Up a Digital Trigger in a CompactDAQ Chassis

[EdoardoA]

Thanks for the quick reply!

Can you recommend me a digital module?

E

[ZYOng]

I believe NI-9401 is the cheapest option for a TTL signal.

You can browse Digital I/O product page.

[EdoardoA]

Is there any option for a module with BNC connections?

[ZYOng]

If you spend some time exploring Digital I/O product page, you should be able to notice which module has BNC connectors.

Among them, NI-9402 has BNC connectors and supports LVTTL. LVTTL is compatible with TTL for input. According to NI-9402 Specifications

[EdoardoA]

Thanks for help, I did check and I found that one too, I want to have a confirmation from you:) by the way, would it be possible instead of triggering the NI9239 with the NI9402 just use the NI9402 and with 2 inputs?

For instance, trigger in channel 1 and analog signal on channel 2 of the same module (NI9402)? Measuring the current from photodiode on channel 2.

Thanks,

E

[ZYOng]

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@EdoardoA wrote:

Thanks for help, I did check and I found that one too, I want to have a confirmation from you:) by the way, would it be possible instead of triggering the NI9239 with the NI9402 just use the NI9402 and with 2 inputs?

For instance, trigger in channel 1 and analog signal on channel 2 of the same module (NI9402)? Measuring the current from photodiode on channel 2.

Thanks,

E

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NI-9402 is a digital I/O module.