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Can I read the dd file without the device

One thing I want to clarify is that the mode doesn't affect the update rate. The mode determines where the value comes from. See the "Configurator User Manual" page 4-25. It would not make a difference if you change the mode.
The response time, the schedule on the bus both determine how fast you can manually operate the device. Devices cannot simply transmit data across the bus at any time because this would cause traffic jams. The Link master schedules the whole bus.  So the schedule you download to the bus also causes some delay. And furthermore, you read and write tags in the loop. Two operations take more time than one.  So I think 200~300ms for each iteration is expected.
Ryan Shi
National Instruments
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Message 11 of 14
  I am currently talking with the manufacturer of the positioner about this issue also.  They are off today because of a holiday.  So far they are not sure why this is happening and I probably will not get an answer until tomorrow.
But I do have some questions about the Link master schedules.  Could I possibly get better results by changing the schedule?  Can I hurt anything by changing the schedule?  If I do change it can I set it back to default?  I was looking through the manual and it says that it is easier to use the configurator software to change the settings, so I will look into it more until I hear back from you.
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Message 12 of 14
If you want to test only this device by LabVIEW, you don't need complex schedule. In Configurator, only drag the AO block onto the "Function Block Application" panel and download, then call the VIs in LabVIEW. If that's all, no other devices, no other communications, the speed would not be affected by the schedule.
I think you should contact the manufacturer first, to confirm if you are reading/writing the right block and right element, and to confirm whether this device can read fast, continuous signals and make smooth operations in time as what you want to do.
Ryan Shi
National Instruments
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Message 13 of 14


I am doing something similar for my thesis, I am going to use Labview 2017, ni usb 8486 and a  filedbus power supply relcom fps-dct.
I do tests in OOS mode (out of service) but I have not had any response from the valve.
Should you only work in Manual mode? It is possible that you could provide me with some screenshots of the vi with which you achieved the movement of the valve. Thank you

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Message 14 of 14