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How can i give digital input to servo via only LabVIEW?


I have a test rig that contains a servo motor and 2 photomultipliers. I use a NI DAQ card to give analog input to servo and to take output from photomultipliers. I have constructed VI programme. Everything works and i can perform my experiments. But, the servo rotates very slowly even if i stop it from LabVIEW VI interface. I think there is a noise due to my cabling between servo and DAQ card. This situation affects the experiment results. So, i want to cancel out the DAQ card in only motor control. I want to try to make a connection between PC and servo via RS232 and give digital input to servo with using only LabVIEW. At this time, i will still use the DAQ card to collect output from my photomultipliers. Is this solution possible and how can i control my servo using only LabVIEW? Thank you all.

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Read the manual for the servo controller and see what it says about how to communicate with it.  Often there is an interface, and very likely it uses ModBUS.

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I have to admit I do not really understand your question but... The servos I have worked with had a "trim" adjust on them that had to be set or you would see the exact behaviour you are seeing.


Send a "stop" command and adjust the trimmer until the servo remains stationary.

=== Engineer Ambiguously ===
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