07-20-2007 01:16 PM
07-24-2007 08:04 PM
Hello Warren,
What about using the Win system DLL call from inside the Query Input Devices VI to build your own piece of code to continuously monitor whether an input device is connected? I believe it might be caused by that shift register inside of the function.
Regards,
Clint M
National Instruments
07-25-2007 09:12 AM - edited 07-25-2007 09:12 AM
Hi Clint,
The only DLL call I see in the Query Input Devices VI that's associated with a joystick is "C:\Program Files\National Instruments\LabVIEW 7.1\resource\lvinput.*" and that is not a DLL that ships with windows. NI would appear to be the source of it. What's more, there appears to a shift-register equivalent data store within the DLL code because, with execution highlighting turned on, it's easy to see that the DLL call will return the same initial call's information over & over again regardless of the subsequent attachment state of the joystick. Yes there is a shift register in the VI, but that does not appear to be the source of my "problem" at the moment.
Thanks for the thought though...
I don't suppose there are any other routines within the lvinput library which I could call to reset the state? Got (lvinput) documentation?
Warren
Message Edited by Warren Massey on 07-25-2007 07:20 AM
04-01-2008 10:45 AM
04-01-2008 12:25 PM
solarburnDOER wrote:
Has a solution to this "problem been found" I would very much like to know the answer as well.
Kevan -
04-10-2009 08:07 PM
04-10-2009 10:34 PM
04-11-2009 04:43 AM
HERE and HERE I have written some Nuggets on direct USB communication. An example is listed for a mouse, but it whould be easily adaptable to a joystick.
Since the communication is in the user's hands, a "missing" joystick can be re-scanned and re-opened programatically.
Let me know if this helps.
Shane.