05-09-2022 01:33 PM
Hi, I am trying to use the NI-9213 in a high speed environment. According to the data sheet it should be capable of reading temperatures 95 times a second or say ~10ms. But when I try and use it I am getting one read ~250ms. I am using a NICDAQ-9181 Ethernet chassis, and I am only reading 2 channels
05-17-2022 04:36 AM - edited 05-17-2022 04:37 AM
And do you use a timed AI task or rather a single point read? With single point read your maximum sample rate sounds about right. For every sample you request, DAQmx has to send a package or two over the network cable to request the sample, wait for the response and then present the result to you.
With a timed AI task you setup an AI task on the target that acquires the data into a buffer and then request that buffer a few times per second. Same network overhead but with each data read you transfer a whole buffer of samples.
05-17-2022 09:59 AM
what I ended up doing is setting up the task by calling DAQmxSetAIADCTimingMode with DAQmx_Val_HighSpeed and calling DAQmxSetSampQuantSampMode with DAQmx_Val_ContSamps.
I didn't want a buffer of temps, as I am trying to sync with a couple other pieces of equipment.