Hello experts, I have a cRIO-9045 with analog output (NI-9265) and analog input (NI-9203) boards. I am trying to create a PID controller with it. I have attached a simplified example of my code (not my actual code, which is far more complex). This example demonstrates my exact problem, though. I have an analog input task and an analog output task with a function block inbetween them. So my output is continually changing based on my inputs. If I run this code as-is, my AO task throws this error: Error -200019: ADC Conversion was attempted before prior conversion was completed This KB article doesn't seem to help me much. I tried reducing the output buffer size (doesn't help). And I really don't want to reduce my update rate (1 kHz is serious goal). If I switch to an "on demand" AO task, it can't execute at 1 kHz. And if I enable "regeneration mode" then my code does execute at 1 kHz, but I am clearly getting the glitching regeneration problem (which is not acceptable). So... how can I get my AO task to output at 1kHz and without errors and without glitching?

I recommend you use Hardware-Timed Single Point Mode instead of sample clock mode for high speed PID controller application.

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DAQmx Analog Output at 1 kHz is "glitching"

Solved!

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Hi all. Just closing the loop on this. I tested it, and can confirm that using Hardware-Timed Single Point Mode solved the crux of my problem, which was the analog output performance in my control loop. I realize there are other issues with my example code, and thanks for everyone's additional tips.

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DAQmx Analog Output at 1 kHz is "glitching"

Re: DAQmx Analog Output at 1 kHz is "glitching"