How to do quadrature decoding using DAQCard6062E?

[Vss]

Hi,

My name is Xiaofei, a beginner of LabVIEW. Now i am dealing with a project involving quadrature decoding by using DAQ Card 6062E and breakout board CB68LP. We need to use 2 optical encoders simutaneously, and for each encoder, we need to use 3 digital channels (A,B and Index), therefore there will be totally 6 digital channels in use. For this reason, is it still good to use the counter channel? or we'd better use 6 DIO?

I'm not sure if there is any existing VI that can help us with decoding, if there is,  could you please let me know how we can find it?

If we will need to make the decoding code by ourselves, could you please give me some hint so that we can start it?

I heard that there should be an example called "How to Count.vi" that shows how to decode, however i failed to find it by using example finder, so does anyone know how to find it?

Thanks a million!!!

Regards,
Xiaofei

[Paul_C.]

Hi Xiaofei,

Our 6062E DAQ cards can be used with either our DAQmx drivers or our older Traditional DAQ (Legacy) drivers.  The example that I've provide below is for use with our DAQmx driver set.  If you’re using Traditional DAQ drivers I would recommend upgrading to our newest DAQmx drivers.  You can click here for help determining what version of DAQmx works with your version of LabVIEW.

To do hardware timed quadrature encoder applications you will want to use the counters on your 6062E DAQ card.  Click here for a guide to using quadrature encoders on E-series DAQ cards.  Unfortunately, our E-Series cards do not support Z-indexing as described in the following developer zone tutorial: Quadrature Encoder / Position Measurement.  However, you should be able to use your encoders without using  Z-indexing.  Each of your encoders will use one counter source and one digital line for your A and B inputs.  The counters will count the edges of the A input while the digital line determines the direction (Up or Down).  A good example can be in the example finder under the following location: (Help » Find Examples » Hardware Input and Ouput » DAQmx » Counter Measurements » Count Digital Events » Count Digital Events.vi).  This example should give you a good start for use with encoder.  You will just want to replicate the code for your additional encoder.

I hope this helps,
Paul C.