Out Port problem

[Alex_Muz]

I am using with Out Port.vi at my Labview 6.0 apllication under Win-98 and it works perfect.

Now I want run the same application under WIN-XP. I followed NI instructions and installed accesshw.dll and accesshw.llb.

The problem is that Out Port.vi is not working after computer powering-up . After Labview Exit and load Out Port.vi  again the vi is affect and the application works perfect.

What can cause this phenomena? 

[smercurio_fc]

I don't think that library has been "officially" branded by NI to work under XP. Whether or not it works is a crapshoot in that case. Are you still trying to run 6.1 under XP?

[Karunya_R]

Hi Alex,

If you are using LabVIEW 6.1 with XP, these VIs do not work in an XP operating system. However, you have used the correct workaround of AccessHW library. After you download the library, please be sure to replace the Out port and In port  VIs with the new set of VIs if you are still using existing code.

This knowledgebase provides more information on this. You might also find this knowledgebaase useful if you want to use another method to access your ports. Are you able to access your hardware registers?

[Alex_Muz]

Hi,

I followed NI instructions and installed AccessHL dll and liberies, then replaced Input and Output port vis in my application. Input and Output port vis are working properly while it does not loaded immedeiatly after computer powering up.

My Labview application is loaded from computer Startup immedeatly after computer booting. During the problem debugging I found that while the Labview application is loaded from Startup or  immedeatly after Windows come up, Labview application can not control parallel port(to add delay as a firs step of application does not solve the problem). While the application is loaded some time afer windows come up(the time is not constant while LAN is not connected about 10sec while LAN is connected about 40sec) the Labview application control parallel port properly.

I think WIN-XP OS holds parallel port control some time after windows come up. If Labview is loaded before WIN-XP OS released parallel port control, then Labview access to parallel port control is denied.

Is it make sense? Is there any way to load Labview application from Startup and control parallel port?

[Karunya_R]

Yes Alex. That does make sense about your conclusion on LabVIEW application is unable to access the parallel port until Windows boots up and releases the port. One thing to do would be to check the mode of parallel port in the BIOS.

Hope this helps.