10-23-2012 12:06 PM
Greetings,
I am having some trouble getting my VI to read from my DAq and a serial instrument at the same time. If I run the subVI's simultaneously (i.e. subANG is running in one window and subVEL is running in a second window) both return the proper values and behave as I would expect. However, if I call the subVI's into a parent VI and try to run them both in the same loop structure subANG gets stuck and will not resond with a change in signal.
I have also tried to use a stacked or flat sequence to separate out the execution of subVEL and subANG, but I still get the no response from subANG.
The most confusing thing is that if I run Parent.VI in one window and then create a copy of subANG (call it '....-copy' or whatever) and run it in a second window, Parent.VI behaves properly and will refresh the readings as they appear in '...-copy'.
I have attached 3 files.
(1) subANG.VI -This reads an RS232 signal from an inclinometer. The signal is refreshed every 10ms or so.
(2) subVEL.VI -This reads raw voltage from one channel on the DAq, calculates the mean then converts that into a pressure differential and finally a velocity based on the pressure and temperature inputs.
(3) ParentVI.VI -This simply calls and displays the subVI's
My guess is that it is a buffer issue, but I am stumped. Does anybody out there in Labview land know why this might be happening? All suggestions welcom.
Solved! Go to Solution.
10-23-2012 12:23 PM
Forgot the attachments. Sorry!
10-23-2012 12:24 PM - edited 10-23-2012 12:25 PM
Oops again. Uploaded the wrong files. Please use these for your reference.
10-23-2012 12:51 PM
I am noticing it is not an NI DAQ card. How are you communicating with the DAQ? If it is using a serial port, that could be your problem.
I also highly recommend using the VISA drivers for serial communications instead of the serial.llb VIs.
10-23-2012 04:18 PM
It's not a serial instrument. It is a UEI PowerDAq with their typical A/D and cable.
I did find away to make it work by placing subANG and subVEL into different while loops side by side in ParentVI.