Message Edited by Mustard on 05-05-2006 02:18 PM
It's actually OK to use the DAQ Assistant inside the WHILE loop. The code is written in such a way that the configuration, start, and stop code is only executed once, and the Write is done on every iteration. If you are interested in seeing how this is done, just right click on the Express VI and choose "Open Front Panel". This will allow you to view the block diagram being used by the Express VI. Be careful though, once you open the front panel, the VI is no longer an Express VI (meaning no more pop up configuration window!), and it cannot be converted back. I'd suggest creating a new VI and DAQ Assistant, and viewing the block diagram of that VI.
As far as your program is concerned, I agree that you are limited because this is a software-timed application. The output can only be as fast as the loop can iterate and Windows can communicate with the device. Lynn made some great suggestions on improving the speed of the WHILE loop, which should make the code run a little faster. However, if you are unable to reach the speeds you need using the USB-6008, I suggest taking a look at the NI motion control products, which were more specifically designed for applications such as yours. See the following link:
I hope this helps!
I am trying to use the Motor Control.vi program to run my digital servo. Exactly how would i connect the digital outputs? Do both go into the 'signal" wire and then I program a separate 5V+ generation DAQ-Assistant into the program?
This thread is nearly eight years old and is unlikely to get much attention. If you have questions on wiring or configuring your DAQmx device I would recommend creating a new question on the Multifunction DAQ forums:
If possible, you should also post the code you have already written as well as a clear description of the behavior you want and the behavior you are currently seeing. Letting us know what hardware you are using would also help.
What do you mean by "digital outputs"? What do you mean by "signal wire"? Are these physical channels or wires on your block diagram? Where did you get "Motor Control.vi" from?
Try and provide as much information as you have or are able to give. The more information you provide, the less everyone has to guess at!