I am fairly new to labview but I got a grasp on the basis.
I am trying to get a linear position info from an absolute encoder but not succeeding. I try to use the VISA but didn't work.
Also when using the DAQ assistant, the encoder is not listed.
PS: the encoder is from Renishaw company:
how is your encoder connected to your computer? Which port do you use?
- The DAQAssistent is made for DAQmx devices. DAQmx is a driver for (only) NI DAQ devices.
- VISA is used for other ports like GPIB, RS232/COM, and some more. See my question above…
Oh right, I wanted to specified it but forgot, my bad.
Well, the encoder has a 9-pin serial end, which is connected to an interface (serial to USB), in order to connect it to the computer by usb.
This is the interface
then it's up to you to determine the serial protocol used by your encoder: Resolute lists a few of them…
When you are sure about that you need to either find a ready-to-use driver for your sensor or to program your own driver based on that protocol. (You need to use VISA functions as it's the serial port your sensor uses.)
ask your vendor? Read the manual?
Somewhere you will find accurate information about your specific sensor…
Page 6 of the E201 datasheet lists the command set for the interface. It looks reasonably straightforward. Responses seem to be terminated with carraiage returns, so it should be fairly easy to get data. Interpretting the data may take a bit of parsing.
Please post what you have tried and tell us specifically what kinds of errors or output strings you are getting.
Well it is really strang, I made a box to choose the port, connected it to a Visa function OPEN, and I got an error - 1073807246, which according to Ni help is:
"The ressource is valid but VISA can't access it for the moment".
My encoder is well connected and not used by something else, at least that I know of.
Is it possible that you installed drivers for the encoder and that it may be running a .dll in the background as some sort of service to provide an interface that their software could use, even if you don't have their software open at the moment?