Referencing Queues by Their Unique Names in Multiple VIs

[ShazilM]

Overview

Using queues in a single producer/consumer architecture is easy to implement with lots of example code available off the community. What we will look at here is another way of dequeuing data out of a queue

Description

Geneally the queue functions can be referenced to each other by simply connecting the "Queue in" and "Queue out" terminals of the function. This is very straight forward and the fastest way to do it if queues are to be enqueued and dequeued in the same VI. But how do you connect these terminals if you are to dequeue elements from a queue in another VI? Or in multiple VIs?

An amazing feature about queues is that they can be given unique names which can be used as references when obtaining the queue. The following example produces random data in two seperate VIs (Producer1 VI & Producer2 VI), each getting stored in separate queues. These queues have associated names to them and are then called in a third VI to dequeue each of the respective queues.

It is important to note that no Ref Nums have been used to locate the queues. This approach can be used in SubVIs or even different VIs altogether. It does not neccesarily need to be a subVI

Requirement

1. LabVIEW 2014 (or compatible)

Steps to Implement or Execute Code

1. Open & Run Producer VI.vi
2. Open & Run Producer2 VI.vi
3. Open & Run Consumer VI.vi
4. Click on the respective "Get Data" buttons to retreive data from the respective queues.

Additional Information or References

Block Diagram

 **This document has been updated to meet the current required format for the NI Code Exchange.**

[crossrulz]

Make sure you are closing those references, otherwise this could turn into a very interesting memory leak.

Personally, I find it best to use an Action Engine to hold your queue references.  The consumer should create the queue and be the only place that dequeues.  Other VIs can just use the Action Engine to enqueue data.