Hello everyone, I want to control a step motor (for rotational stage), a Keithley 2450 and an SR830, changing the stage degree step by step while measuring the Vac and Idc with continuously changing Vdc. The outmost while loop partially shown in the picture below is for changing degree by the step motor. The sequence structure and two inner small while loops is for measuring Vac-Idc-Vdc. What I want to do is to show the real-time xy plot during the measurement and show the multiple xyplots for different degrees (one single xy line for one degree). So I add the disabled part and the problem comes. When I disable the part, everything works fine. All Vac and Idc values are measured with apppointed Vdc range (such as -10 V ~10V). But when I enable the part, the two loops end half way. I wire the errorout of write to measruement file to the shift register for errorin of the out most while loop, which doesn't work. I am totoally confused. Can anyone help me out? Thank you. Zhu

I'm seeing one major issue. It is a classic example of not all of the data being processed in the consumer loop due to following NI's example. So you have one loop adding data into a queue. You have a second loop removing the data. The producer loop completes and destroys the queue. This causes the consumer loop to throw an error due to the queue being destroyed and stopping. But what happens to all of the data still in the queue when it is destroyed? Answer: it is GONE. It will not be processed. Since you want every peice of data processed, you need to send a command of some sort to the consumer loop to let it know it has processed everything and then allow it to stop. Only after the consumer loop has stopped should the queue be destroyed. So what command should you use? In this situation, I would send an empty array when the producer loop has stopped. The consumer just checks the read data to see if it is an empty array. If it is, it stops the loop and destroys the queue.

LabVIEW

while loops end earlier when there is a cluster array for multiple xyplot

Solved!

Author

Hello altenbach,

60000 was what I just copied from an example from Keithley 2450. I have changed it to 16.

A graph with multiple plots. I know that for every single inner iteration, it has to plot every previous points measured since the whole vi starts. I think it takes lots of time. Is there a better way to do this?

Best