Triggering from multiple trigger sources?

[Podoba]

Hi,

I have a PXI system with four ADC in it. Also I have four trigger sources one for each card.

In some regimes I need to start all ADC cards simultaneously using that triggter which comes first. I do not know which of the triggers will be first. Is there any ways to realize it in LabView?

Thanks in advance.

[John_P1]

You didn't mention what hardware you are using, but M Series DAQ boards support change detection which could do what you need.

If you don't have hardware that supports change detection, you could always use an external OR gate.

Best Regards,

[Podoba]

thanks for reply.

I'm using S series NI PXI-6123 in four slots of PXI-1044 Chassis.

What do you mean under external OR gate? additional hardware?

If the RTSI bus could help me in this case?

[John_P1 · Accepted solution]

Hi Podoba,

The 6123 does not support change detection, so the best course of action is probably to use an external OR (or NOR) gate with 4 inputs.  You can connect your signals to the inputs of the OR Gate, then use the resulting signal to trigger your DAQ devices.  If you use a NOR gate, then you would trigger on the falling edge.

The "additional hardware" is really is just a simple IC.  You can probably find something that suits your needs on digikey (example search parameters below):

       

Best Regards,