PCI-6071E multiple scan clocks

[eLions]

Hi, we plan to use PCI-6071E to measure voltage signals from two photodiode arrays (PDA). Detailed implementation is following: 

Operation mode: Analog input, continuous acquisition,external sample/scan clock (Rate~100KS/s), external start trigger

Software:  C++ based on NI DAQmx

Start with example code "ContAcq-ExtClk-DigStart.c"

We plan to use one analog channel for PDA. Each PDA sends out a series of trigger singals (which is going to to be used for 6071E as sample clock), one Low-to-High edge for each pixel. The experiment is configed such that very likely we can use the same start trigger for the two PDA inputs, but their sample clocks might have a relative delay (typically a few microseconds). We certainly prefer to acquire data from each input channel in regard to its own sample clock.

Is it possible to do this? How? 

Our initial guess is to program two TaskHandlers, each configed with its own sample clock (maybe start trigger as well), and start/read/stop almost at the same time. Does this sounds reasonable? If so, our final goal is to work with two more PDAs (a total number of 4). What is the limit of sample clock number if all acquisition is done sinmutaneously? 

Thanks for your solutions and comments in advance.  

Kunyan

[Brandon_B · Accepted solution]

Hello Kunyan,

Unfortunately, with the 6071E you only have one PFI line (PFI 7) for external sample clock use, as well as one PFI line for AI start trigger use.  You can look in the 6071E Specifications to see these lines.  You will most likely have to run all of your PDA's off of the same sample clock and start trigger, unless you would like to use multiple DAQ cards.  I hope this helps.

Regards,