11-17-2010 10:36 AM
Hello,
I want to add filter to my counters inputs because there is noise in my input : I have trouble in measurement of quadrature encoder with 6601.
I must use I/O Config Register, Pins A through D , Input Select <2..0> but there is no exemple for quadrature encoder. How can I implement this function?
11-22-2010 03:33 AM
Hi SteFaNy,
What kind of noise do you have?
Is your application in polluted environment (presence of motors, electromagnetic waves...)?
You can use a digital filter to remove any bounce at the output of your encoder. If this is not enough, I invite you to create a filter to remove spectral components that are the problem on your encodeur.
Access to the digital filter is via property node as shown in the link below:
http://digital.ni.com/public.nsf/allkb/220083B08217CFD686257131007E5D2C?OpenDocument
You can find several exemple from the tool "exemple search" of labview with the déscriptions: "measure angular position"
Regards,
Rémi D.
National Instruments France
11-22-2010 11:06 AM
Hi Stefany,
There is an example for quadrature encoders in the DDK -- gpct_ex7.cpp -- and it uses the default values of the I/O Config Regsiter -- all zeros -- which means that the pins are input-only and are unfiltered. If you would like to enable the digital filters, refer to the documentation for the I/O Config Register in the NI 660x RLP Manual [1]. By setting in the Input Select field to non-zero values, you can enable different digital filters. The manual also describes reading quadrature encoders in Chapter 2, page 2-9 (which is page 26 of the PDF).
[1] NI 660x RLP Manual
http://www.ni.com/pdf/manuals/370505b.pdf
Joe Friedchicken
NI Configuration Based Software Get with your fellow OS users
[ Linux ] [ macOS ]Principal Software Engineer :: Configuration Based Software
Senior Software Engineer :: Multifunction Instruments Applications Group (until May 2018)
Software Engineer :: Measurements RLP Group (until Mar 2014)
Applications Engineer :: High Speed Product Group (until Sep 2008)