Hi, I'm trying to set connection from PC to cRIO9030, by USB->RS232->RS485 converters. When I'm sending data from PC on RT I'm getting invalid values, for example when i'm sending 65 number, I'm getting 57B7, 0 gives me F8F7 etc...

Yes. That is better. It is very strange. I don't see anything obviously wrong in LabVIEW with the way you are handling data. Though one thing you should do is add a small wait function into your sending VI. Right now, it is sending data as fast as it can. Though I think it would be more likely to give you buffer overrun errors rather than data corruption. One more thing, put an error indicator on your wire in the receive VI so you can see if you are getting any parity or other serial errors there. I took the values being sent and received and looked at their hex and binary values to see if there is any pattern there, and I don't. Though it is "almost" inverted 0's to 1's and 1's to 0's. I would double check your wiring. Make sure you didn't swap the polarity of the RS-485 wires. Though I think if that happened, you'd likely see a lot of framing errors. See if you can swap out any equipment, like if you have another RIO, or another RS-485 port on the same RIO. Or if the RIO has an RS-232 port try doing an RS-232 to RS-232 with a null modem cable. That would at least confirm which parts (such as LabVIEW code) are operating correctly.

LabVIEW

RS 485 communication between RIO and PC

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You were right, I should triple check my wire connection. When i crossover properly Tx with Rx it started to work good.

Thanks for Your help 🙂

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RS 485 communication between RIO and PC

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