Wait function slow

[Testr00]

I have a executable of a program that uses the Wait function to control how long a parallel port pin is held high. On 2 out of 3 computers running this executable, the timing works as programmed. On the odd one, the timer seems to run slow because the pin remains high for much longer than it's set to. All computers are running Windows XP Pro with the same hardware. The only difference is the slow pc doesn't have LabVIEW installed on it. Does anyone know why this is happening?

Thanks,

Ricardo

[Chris S]

Are PC configuration (RAM, processor, Etc..) identical ?

I think that the RAM memory is the trick !

[Testr00]

The processor and RAM are the same (AMD 3200 & 960MB memory).


Message Edited by Rnojima on 07-30-2008 07:08 AM

[Chris S]

"with the same hardware" Sorry I didn't see : )

It looks like something with memory.. May be your hard drive is full, may be your RAM is dead (Check into system configuration).

Chris

[Testr00]

Hmm, the hard drive has 85% free space. There has never been any indication of memory failures in using the "slow" PC - don't have any kind of odd crashes or blue screens.

[Chris S]

OK... So :
- your LabVIEW code is OK
- the computer hardware is OK
- the computer memory is OK

May be you have something runing on your computer (large application or viruse ; ) ) that slows your program..

Sorry I don't have extra idea.
Indeed, for me it doesn't mater that you do not have LabVIEW installed on your computer, since an executable uses LabVIEW runtime.

OK maybe somebody else have an idea !

Regards,
Chris

[Pnt]

I don't think it's the wait function.

Make a simple exe (with wait function), which counts seconds and run it. I will be very surprized if there is a PC which counts wrong.

Maybe you can post your code or an image. 

[JeffOverton]

Yeah, my first guess would be that your code is stalling for some amount of time before your wait is called.  Whether that particular computer has something else that is trying to use the parellel port or something, I don't know, but my guess would be along those lines.

Message Edited by JeffOverton on 07-30-2008 08:50 AM

[Testr00]

Thanks to everyone for their input.

PNT, you are right about it not being the Wait function. I created a couple of apps to test this using just the Wait function and also the Tick Counter function and both work correctly on the slow PC.

I ended up fixing the problem by setting the parallel port to ECP & EPP mode in the bios. I'm not sure why that fixed it. It was in standard mode before. I thought I had read somewhere that the in/out port functions required the parallel port to be in standard mode.


- Ricardo

[Pnt]

weird..!