Timeout error using MODBUS RS-485 at cRIO-9039 and mod 9871

[MarBry]

HI

I use cRIO-9039 and mod 9871 to communicate with RS-485, i alsow use modbus library.

Everything is working while i using USB/RS-485 converter but failed when i try to send orders to my device by cRIO.

I get only Timeout error (56).

I use Scan Interface.

I use port ASRL11::INSTR. I pluged the in the power to my device (mod 9871).

Do you have any idea why it happen?

[n_dakota]

Hello,

Did you see this KB?

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019Lz2SAE

[MarBry]

Hi,

Thank for your replay. I use modbus protocol and i communicate with devices - i only have access to their address at RS485. I tried everything from this KB but i didn't find anything useful.

Mark

[LM98]

hello, I get the same problem as you and I would like to know if you were able to solve it.
I want to do a Modbus RS485 communication with SB-RIO 9626 in order to control a temperature.