Acquire encoder position with Motion and DAQ

[superfunk]

Hi,

I am trying to acquire an encoder position with Motion. It seems impossible to set the frequency of the acquisition with Motion and I must poll for the position in a do-while loop.

I have read in a lot of threads that one can use RTSI lines to retrieve encoder position with a DAQ Board though it is acquired with a Motion board. But there are no examples at all about this.

To sum up, I need to send Encoder Phase A to RTSI0, Encoder PhaseB to RTSI1 (which I already do), retrieve info with a DAQ device and then calculate rpm.

Christophe

PS: please don't answer with measure angular position.vi or explain me in what this Vi can help me

[superfunk]

To be fully accurate :

DAQ : 6230 (i don't see any RTSI terminals, only PFI or trig)

Motion : 7774

Labview 2010

[superfunk]

I have managed to read RTSI lines with the counter of my Daq card... but I still have a problem of sample rate since I am using a counter.

I acquire an angular position but I can't derivate it to get velocity since the slopes are identical.

How could I use a user defined frequency? I have thought of using 2 numeric channels of the DAQ but I can't read anything from them

Christophe

[Rojam06]

Hello.

Could you upload the Measure Angular Position_DAQ.vi  in 8.2 version. thanks

[superfunk]

Yes!

here you go

[chat-relotte]

Hi Christophe,

I'm not sure I understood well what you need. You have the angular position and you need to know the timing, am I right? Can you use an other counter on your card to get the period (or the frequency) of your signal? From that, I think you should be able to calculate the velocity.

I hope this helps,