Digital Outputs / Analogue Input controls

[Fletch]

I'm starting to make progress but i'm still a novice so I just need confirmation i'm on the right track.
I'm designing a system to control test fixtures. Each fixture has multiple stations. Each station requires DO's to control pneumatics and has AI's determing its function.
I've setup each station as seperate vi's and seperated AI from DO. I've used a global VI to interface all the individual station Vi's to caputure the info and control the pneumatics.
I'm currently running a low spec laptop (times are tough) with a 16 bit PCMIA card. I've noticed that the timers are skipping and the outputs are sporadic. Is this a physical problem with the hardware or a programming issue? The station vi's run fine seperately
(1 milli-second while loop precision setting). I haven't got a buffer vi, could this be the problem?
I've only been using labview for a few weeks and i'm self tought so keep any replies in lay-mens terms (if possible).

Many Thanks...Mark

[Doug C]

Hello Mark,
The first thing I would look into would be memory. If you are on a low end laptop I am assuming you do not have much memory. LabVIEW eats up memory real fast when you use Globals. Not only is there a memory location taken for the global, but each time you call it in the VI you are making a new copy of the global, therefore a new memory location it taken. That could causing the other parts of the program to slow down, like the counter timers skipping.
I hope this helps,
Doug