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sbRIO-9651 on DevKit - RS485


I need to use the RS-485 port on the sbRIO9651 with its dedicated NI DevKit.

I understand how to use the CAN-bus. I generated the required clip for both CAN-bus and RS-845.

The CAN-bus is operated directly from the RealTime target: I have found dedicated block in the block diagram palette.

What about RS485?

Do I have to open a VISA sessione o what?

Thanks a lot,


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Message 1 of 4

Hi AL3,

Yes, the VISA API is the driver needed to communicate with the onboard RS485 port.  The VISA API has properties and methods for configuring and writing/reading RS-232 and RS-485 interfaces.

In addition to configuring the CLIP with CAN and RS-485 interfaces, you will need to compile an FPGA VI (could be a blank VI) with the CLIP added to your project, and load that bitfile onto the sbRIO-9651. That bitfile could be loaded into the FPGA flash, or loaded by calling the Open FPGA VI Reference when your program initializes (before any VISA or CAN driver calls are made).  NI recommends that the bitfile be loaded to flash, so the CAN and RS-485 perhipherals are connected before the processor OS is fully booted.



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Message 2 of 4

Hi Spex,

Thanks for you clear explanation.



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Message 3 of 4

From RT side, there is no difference if you are using 232 or 485, so just

open visa port you can operate it.

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Message 4 of 4