SCADA with wireless transceivers....

Our supervisor was fascinated by the new Wireless transceivers and now we have two FreeWave transceivers with an assumption of implying peer-to-peer messaging over DF1. We are using two ControlLogix 5550 controllers with Devicenet, ControlNet, Ethernet and DH+/RIO cards installed in them. We have been doing some research on how to use peer-to-peer messaging over DF1 but, haven't found a lead yet. I have been looking at other options like, using protocol switchers e.g. DeviceNet to Serial (RS-232), Modbus to serial etc..

My questions are:

1)Is it possible to use peer-to-peer messaging over DF1 (the serial port on the controller) or is the port used for programming the controller and using master/slave polling? 2)Has any one used Protocol Switcher e.g. converted ControlNet to serial OR DeviceNet to serial and transmitted in serial?

Any sort of advice will be highly appreciated... Ravi..

Yes and no.

You'll have to write some code (several rungs of it in RLL) in both PLCs to transmit data out of the serial port of one controller and receive it at the other one, including error checking and re-transmission. Once the data is read, then switch and send data back the other way.

No... and I wouldn't want to try either. Too expensive.

HTH, Cameron:-)

Hey cheers for that. The peer to peer control is working on DF1 but, peer-to-peer messaging gives me no lead at all. I have done peer-peer messaging via ControlNet which is real easy to setup...AND same thing with DeviceNet too (easy). As you were saying about writing some rungs, I have used the MSG instruction with a controlnet bridge added.. Cheers

I don't quite understand what you mean by "control" and "messaging". If you have peer-to-peer working already then what is your real question?

Cameron:-)

Hmn... i guess i wasnt clear...!! :) Well, if ControlNet is used you can select the remote device from the controlnet bridge this sort of setup is what i meant by MESSAGING. And if two ControlLogix(5550) controllers are connected via DF1 this sort of setup doesnt let us select devices from the controllogix controller.. The master and slave setup with full-duplex via DF1 of the Controllogix controllers is what i meant by CONTROL. Cheers..

Okay.. In that case, you can't do peer-to-peer "messaging" over DF1 - it's not a network protocol.

Cameron:-)

any data can be wireles as long as you bring it back to the original platform Balki