04-09-2020 04:22 AM
I am not familiar with chunks and i couldn't really find something on the internet about it. Can you explain something about chunks or give a link where i can find some explanation about it?
04-09-2020 06:46 AM
@WillemNL wrote:
I am not familiar with chunks and i couldn't really find something on the internet about it. Can you explain something about chunks or give a link where i can find some explanation about it?
A chunk is just slang for 'more than one sample'.
Your DAQ AO is now set to output one value per cycle.
You can set it to 1D Array, and output 100 or 1000 samples at once. Of course you can't use auto indexing anymore. You can use the iterator i, and multiply it with the size. Then use Array subset to get data from index iXn and length n. Or put the array in a shift register and use Delete From Array to get the sub arrays from the beginning, and pass the remaining array to the next iteration. This will be CPU hungry if the array is big (megabytes).
This will let the HW determine the output rate. If you don't supply the next chunk in time, you'll get an error. But this timing isn't very strict. The DAQmx has a buffer, and you can add chunks to it. As long as the buffer it's not full or empty, DAQmx will output the data to the hardware.
04-09-2020 07:16 AM
Okay i will try that! Thanks
04-09-2020 09:36 AM
I think i got it, you write with the subset array a part of the array before the loop to the DAQmx. But how do you control the output rate with the hardware? The hardware i am using is a simulated NI cDAQ-9178 with a simulated NI9263 module.
04-09-2020 11:22 AM
I'm not that much into DAQ, but (simulated) devices that support buffered output define their frequency in the task. This can be in Max or in LabVIEW (if you create a task in LabVIEW). So for you the easiest way would be to change it in Max, where the task is defined.
04-13-2020 05:06 AM
I already tried some things but I close this topi because i already have the solution for my first question so thanks!!!!
04-14-2020 01:31 AM
@WillemNL wrote:
I already tried some things but I close this topi because i already have the solution for my first question so thanks!!!!
You're welcome. Hope to meet you at a Dutch LabVIEW user event someday, if\when things are back to normal.
04-14-2020 02:53 AM
I will look out to the event! 🙂