UNITY PRO 11 SIMULATOR with modbus TCP

[JEANST]

Hello
i want to implement a Read_var / Write_var functions to communicate with
a modbus tcp device
at the moment i use the unity simulator at the office



I made a try with the Ananas modbus simulator and it's working well but..



My question is

is the unity simulator is able to communicate with a real physical device, i can not establish the communication until now on te real module..


Is anyone have an idea


Thanks

 

[Lare]

Not sure if it is still same. Communication to outside is probably inhibited.
http://www.plctalk.net/qanda/showthread.php?t=106594


Anyway, at least you can read modbus data directly from same simulator to PLC program. I have sometimes tested communication blocks and readed %MW data from different memory area from same simulated PLC to data arrays.



Then changed only data index and IP address to real equiment on real PLC.

 

[drbitboy]

My question is

is the unity simulator is able to communicate with a real physical device, i can not establish the communication until now on t[h]e real module..

I assume OP is asking about a "real physical device" with an IP address other than 127.0.0.1 i.e. than the "localhost" address of the PC where the Unity simulator (and the Ananas Modbus Simulator?) is (are) running.

The first thing to check would be the Windows firewall, to ensure outgoing connections to Port 502 (Modbus) at an external IP address are not blocked.

Second, it may be that the Unity simulator restricts Modbus connections to non-localhost IP addresses for business reasons i.e. to prevent the simulator being implemented as a "free" (to use) PLC that uses Modbus as a fieldbus for I/O.

That said, it's a bit fiddly but not too complicated to tunnel (not forward) Port 502 (Modbus) of a real device to Port 502 of the PC (localhost) where the simulator is running, so the simulator "thinks" it connecting to something like the Ananas Modbus Simulator on the PC, but the packets pass through the tunneling software to the real device. I would use PuTTY because I know it, but I suspect there are other packages.

See item (ii) in my .signature below.

[Edit: change forward to tunnel]

 

[drbitboy]

... I suspect there are other packages.

TIL it is simpler than I thought: it is built in to Window apparently; cf. here.

 

[JEANST]

Hello Guys thank you for replying to my question
I give you a little feedback
It seems that the simulator is not able to communicate with physical devices, yes it could be a convenient "free" solution for some people and i assume that schneider is not really agree with that. By thinking about it , it makes a lot of sense. So i have connected my module on the real plc and the modbus tcp connexion has worked very well quite quickly. I keep the idea of tunneling the port 502 it can be useful in some situations.

Thanks again for your help