RIO network protocol documentation

[tlf30]

Does anyone have information or documentation regarding the protocol used in Rockwell's Remote IO, and how the physical layer of the network works?

I am thinking I would like to build a small RIO adapter/scanner on the bench using an Arduino or other small board that I can interface to via USB.

Thanks,
Trevor

 

[Ken Roach]

You aren't going to find one, at least not without burglarizing some homes and offices near Cleveland.

The RIO and DH+ physical layer relies on a Manchester decoder chip, and the protocol is purely proprietary. While some companies successfully reverse-engineered the protocol (and got sued for patent infringement until the patent expired), only a tiny handful are still producing products using it (Prosoft and QTS).

I don't know if QTS has come up with an alternative Manchester decoder or if they've bought up the worldwide supply and it's going to be sufficient for an indefinite period now that RA isn't building products with them anymore.

 

[FearTheNoFear]

Check out SoftPLC. You might be able to use the Arduino board and the SoftPLC hardware as the interface.



http://softplc.com/products/comm/ab_gateways/

 

[tlf30]

Hmm. I did not realize that this was going to be hard to track down.

@Ken Roach Could something like this work if coupled to the correct driver?
https://ww1.microchip.com/downloads/en/Appnotes/00002371B.pdf
I'm not sure the voltage on RIO, but I can test it when I get home.

@FearTheNoFear, I was hoping for something a bit cheaper. $2k for the base model is a bit outside my budget for a hobby project like this.

I'm thinking that if I can figure out how to encode/decode the signal, then reverse engineering the protocol should not be too bad.

 

[FearTheNoFear]

Ah, i thought you were trying this for work not hobby. Seems like a neat project! Good luck.

 

[JeffKiper]

If I was in your shoes I would looks at Ethernet I/P as RIO is dead from ROCKWELL. Moving forward with an Ethernet I/P solution can move to different control platforms instead of an old obsolete PLC that no one wants to support.