RE: How to control DC motor using NI Motion in C programming

[Nabeel9172]

I am using NI Motion card UMI-7764 and using c-language to control DC motor. I am using flexmotion library from NI and able to read the encoder value from NI Motion card using the function  flex_read_encoder_rtn(boardID, axis, &encoderCounts). Now I am willing to control a dc motor using PID control depending upon my desired position but I don't know how to send the output of PID control to the DC motor conneted to my NI Motion card. Please guide me how can I do that. 

Right now I have tried function flex_load_dac(boardID, NIMC_DAC1, (positionCommand), 0xFF) but it is not working.

Thank you.

Best Regards

Nabeel

[BoKnows]

If you navigate your Start Menu to All Programs->National Instruments-> Motion -> Documentation, do you see examples listed in that folder?  There are several examples that should provide a starting point to control a motor there.

[Nabeel9172]

yes I have checked that folder but there is no example. I can read the encoder value from NI Motion card but when I am trying to set voltage to roate motor, it is not rotating. I have made the program in LabVIEW and it is working fine but I have do it in c-language. Any help?

[Nabeel9172]

could you please guide me what is max sampling rate of NI Motion card??

[Nabeel9172]

I am using the attaced code provided by NI but motor is not moving at all, is there any configuration problem? but when I am using LabView code it is working file that's I am thinking that my configuration is correct. please guide me.

[BoKnows]

Does the code return any errors or does the motor just not run?

I'm assuming you've made no modifications to the hardware setup itself.  You're just changing from LabVIEW to C and using the identical setup.  Is this correct?

[Nabeel9172]

yes.hardware setup is same..Now motor is working but throughput of my application is 3ms. Is there any way to reduce the throughput of application from 3ms to 1ms?
Thank you.

[BoKnows]

Did you choose the same profile you were using to see that behavior on LabVIEW or were you also getting 3ms with LabVIEW?

[Nabeel9172]

yes I am also getting 3ms in LabVIEW.

[BoKnows]

Motors have maximum limits.  Are you reaching the maximum for your motor?  If not, take a look at this: http://www.ni.com/product-documentation/4938/en/