Groov Rio not communicating with RS485

I have a Groov RIO that I am trying to communicate to modbus devices via RS485. The Rio sees the usb-RS485 adapter and assigns it \dev\ttySer0. I add that into node red and send coms to the port. I never get an activity send or receive at the adapter. If I plug it in to other devices the adapter works and controls the devices.

The device is a Waveshare USB-RS232/485/TTL adapter. I have used them in several project excellent results on other devices.

Any thoughts or help would be appreciated.

\dev\ttySer0 is what the adapter gets mapped to.
As you say, Node-RED see’s it, but can you please try its native \dev\ttyUSB0 and see how that goes.

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Hey Karl. I use this RS485-to-USB adapter with our Rio’s to receive Modbus data.

As for the node to use, I stopped using this one because it was not being actively supported and we did experience some glitches over time. We moved to these nodes and never looked back.

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Hey guys. I am currently working with device that uses RS-485 connection. Is there anyway of using the connection without any converter/connector. To be exact I am currently working with MP Filtri ICM 4.0.

Glenn, welcome to the forums!

The RIO does not support serial via its I/O pins (The EPIC has a dedicated serial module for it), so you must use the USB port and thus a USB to serial adapter for any serial communications you need to do.

They work very well and are very affordable, what is the reason you would rather not use one?

Thank you, Beno. Actually, I am just making sure if Rio pin cannot process RS-485 connection.