Modbus TCP App - Server Subscription Error - DL_INVALID_ADDRESS

[star_board]

Hello,

Iam using the Modbus TCP App to configure a Modbus Server. I've successfully set up the primary server parameters, such as the IP address, port, unit ID, etc. However, I encounter an issue when attempting to create a subscription.

I have tried to use both PLC DataLayer nodes, as well as system nodes on the field "Node Adress":

I consistently receive the error message "DL_INVALID_ADDRESS" every time I attempt to save my configurations:

Thanks in advance 😉

[Sudeep · Accepted solution]

Hi,

The "start address" for holding register is wrong. 

Holding Register address range is from 3001 to 4000.

Input Register address range is from 4001 to 5000.

Can you please try using "start address" with the range specified above for holding register.

Also may I know which version of the app is being used.

[star_board]

Thanks! It worked now! I also found it in the documentation of the app:

That means that I only have 999 available registers to use in the server app right? 
Another quick question. How can I delete a configured subscription? the Buttons appear blocked in my UI:

[Sudeep1]

You're welcome!
Yes, you will have 999 holding register and 999 input register available to use in server app.

Can you please let me know which version of Modbus TCP app you are using? I can share bit more info on why the server subscription deletion is greyed out or blocked in your UI.

[star_board]

I have tested this with version 2.6.3 and 2.6.1., and in both instances, the icon for deleting server subscriptions is greyed out within the App UI. Additionally, I attempted to remove the associated child node in the Data Layer, which resulted in the following error:

[Sudeep1]

Thank you for your reply!
As of the versions which you've tested (2.6.1 and 2.6.3) "server subscription" deletion is not supported from web UI, even from datalayer it isn't supported.

Please let me know if you have any further questions.

[star_board · Accepted solution]

Thanks for the help! 😊

I successfully managed to delete subscriptions using the method described below. I'm sharing it here since it may be helpful to others:

1. Switch to Service mode and disable the app.

2. Access "Manages app data".

3. Change to file view.

4. Access modbustcp/server/instances and delete the relevant .json file.