Multiple analogue output problem

[Mojito]

Hi all,

I want to control a system that is composed of 2 Galvanometers, a laser shutter and a camera trigger. I have at my disposal a USB 6259 OEM DAQ board.

The 2 galvos need to receive a triangular -3/3V 400Hz signal. The laser shutter needs a user activated +5V for closed and -5V for open. The camera trigger will be 0/5V square wave with variable freq.

Each component family needs to be independant in the sense that I call/activate the signal at different times during the program. Which is why I created 3VIs (one for each type of signal) and have them in different slave loops waiting for the master to call them to activate. Each VI calls/creates their own task.

The Problem: I can call and generate the first signal (0/5V square wave), but as soon as I call the 2nd VI to generate 2 triangular waves for the galvanometers, Labview crashes with Error 50103 saying the board is out of resources.

Why can't I generate different signals and send them from different outputs?

Thanks for your help in advance 🙂

[Dennis_Knutson]

As has been discussed numerous times, you have a single D/A with a single convert clock. You cannot create multiple tasks. You must use a single task per hardware resource. I would suggest a digital or counter task for the 0-5 volt signal.

[Mojito]

Hi Dennis, that's what I thought unfortunatly. How would you create a -5/+5V TTL and a 0/5V square wave digitally? I looked at the examples and the paramaters about 'lines" was confusing for me.

[Dennis_Knutson]

You would need external circuitry to generate the -5 volts from a single digital line. This would seem to be a static wire. And as I mentioned, look at the counter for generating the square wave.