Groov EPIC and Modbus TCP

I was just testing out the upcoming release for Groov EPIC and the Modbus TCP functionality that will be built into the controller and wanted to share some information.

Modbus TCP in Groov EPIC will work just as it did in SNAP PAC for talking to your Memory Map locations. It does not use base-one addressing and you can still find the Unit ID and Register Address for any scratch pad location with the Modbus Calculator in PAC Manager. The PAC Manager User’s Guide for Configuring Modbus Options may be useful if you have questions.

The modbus guide has been updated to include the EPIC processor and I/O.
You can find it here;

The Modbus Protocol of PAC controller can be disable by PAC Manager.
How to disable the Modbus Protocol of EPIC-PR1? We don’t find any document to mention it.:pray:

From groov manage. Click on Security -> Firewall.
Scroll down to ModbusTCP and turn off the firewall, then click save in the top right corner.

Will make a note for the docs team to make that a bit clearer.

Hi Beno, thanks for quick response.

We had PAC Control Code of Modbus/TCP master. It can be work properly in PAC-R2 after use the PAC Manager to disable R2’s Modbus Protocol.
But this code can not work in EPIC even we turn off EPIC Mobus port from the firewall. .
The Communication Handles = tcp:502.
PAC control always get the Error Code:-440 when do the command:ListenForIncomingCommunication.
The PAC Control will be crashed when we iinspect this Communication Handles.
How to disable the port 502 in EPIC???

Error -440 is ‘Could not bind to socket’.
Because you shut the firewall, port 502 is now no longer listing, so pac control gives the error that there is nothing to connect to.
Port 502 is shut/disabled and your code confirms that.

The question is very sample:

The same code for PAC R2 and EPIC:
chMB_TCP_Slave_Port =“tcp:502”
iMB_TCP_Port_Status = ListenForIncomingCommunication(chMB_TCP_Slave_Port);

In PAC R2:
Disable R2’s Modbus Protocol by set R2’s Modbus Port = 0.
Run R2’s code. The iMB_TCP_Port_Status = 0.
In EPIC : Modbus TCP Port: 8502 Daney: Eth0, Eth1, wLan0 or Allow all
Run EPIC Code: The iMB_TCP_Port_Status = -440.

Do you need our code to test?

Port 502 of PAC-R2 is also shut/disabled, but R2 can be connected by Modbus Client. Why?

Please send your question and code to suport@opto22 dot com.
They will need to test your code on both the R2 and EPIC.

Hello Beno,

We are also facing the same issue with EPIC.

We have a KB article on this issue now.
Please review it and ask any questions here or to our support team.

Hello Beno. Thank you for such a valuable information. Please tell us what should we do if we want to use port numbers below 1024.