Hello Veejay,
After looking over this post and your code, I think its best if we back up and break down this problem some more. In order to do this, I would like to know what the differences between each channel (elevation and speed). From reading your post all of these will be differential voltage measurements but will they all have the same range or do they each need a special scale?
After figuring this out, we need to know if you need a buffered measurement (multi-point acquisition) or single point acquisition. From looking over your VI it will need to be single point acquisition. With this information, we can build a simply VI that acquires the data correctly and then we can break it up into subVIs and then a state machine.
When create a state machine you should think about states like idle state (do nothing state), Start Task, Read Values, Stop Task, and Stop VI. The Initializing and closing part of the task should be outside the while loop where it will run only once.
Also, using reference like you have isn't the best way to go. In LabVIEW it is best to use data flow where you pass values into subVI. When you pass reference to all you subVI, it is very possible to run into a race condition especially when 2 subVIs are using the same references.
Jim St
National Instruments
RF Product Support Engineer
