I use the Relaismodul from Quancom too. I communicate with them through quapigetdi8.vi and quapiputdo8.vi. In my program I communicate with a devise per USB to RS232 and with many devises per USB to GPIB. If my program is finished and I want to restart it again, I have the problem with USB Relaismodul from Quancom. I habe to restart my PC again and then I can start my program again. I would like to know whether it is possibly to work without restarting PC. I work with Windows7 and labView2011.
So, your problem is that once that you stop your application, if you want to launch it again (communicate again with your devies), you are forced to restart your pc? Are you getting an error message if you don't restart your appliation? if so, could you send me the content of this error message?
Are you using VISA functions to communicate with your devices?
Where did you downloaded the quapigetdi8.vi and quapiputdo8.vi ? I would like to take a loot at it too
If your program is not too heavy, could you add it to this forum so that I can take a look at it?
Do those VI's close the references to the COM port? You can set up a blank VI with a "close VISA" and wire a control. You will see in the control dropdown if the port is still open.
Are you able to restart LabVIEW an get them to work, or is it only a PC restart?