[Matter] Is there an example/tutorial how to deal with subscriptions / readings of an Cluster - Attribute with a device (not with CHIP Tool)

[Benny Nestler]

Hi Nordic's,

is there a description or example available for my mentioned issue?

I want to subscribe one device/node to another one. For example:

I have extend the template-example with the thermostat-Cluster. I put it on a device wich measure the temperature and which are able to set a new set point to control the temperature. On a second device I want to read out (or get informed if LocalTemperature changed) the attribute LocalTemperature from the thermostat-Cluster of the first device.

How I have to implement the subscription or the read-out command?

Is that also a binding?

Best regards,

Benny

[Marte Myrvold]

Hi Benny,

Subscription is not a binding. Subscription is a general mechanism of Matter's Interaction Model, and Binding clusters are not involved in that process. 

We do not have any examples or tutorials for this besides using the CHIP Tool. I will look into this and get back to you tomorrow.

Best regards,

Marte

[Benny Nestler]

Hi Marte Myrvold ,

okay thanks for your support, I will wait for your answer :-)

[Benny Nestler]

Hi sigitas ,

I'm very interested in your code snippet, if it works in your linux application.

I read your previous code snippet and your methode SensorsWorkerHandler(). I wonder that there is no "destinationID" for requesting the attribute you want. How does this function know about the node from which the attribute should read from?

[sigitas]

Hi Benny Nestler 

Application first need to establish session with "CASESessionManager::FindOrEstablishSession" where you provide ScopedNodeId as a destination. Once device is connected, application can save session object.

In above code snippet: 

aDevice->GetSecureSession().Value(),

it has information about destination node.

[Benny Nestler]

Hi sigitas 

are you successful with your project?

Can you read attributes from device A with a device B?

Best regards,

Benny

[topraveenpaul]

 sigitas 

I'm in this same situation wherein i need to get a stateValue of a subscribe event.

Currently, i use chip-tool as below.

./chip-tool interactive start

>> booleanstate subscribe state-value 1 1 120 1

Also as standalone, 

./chip-tool booleanstate subscribe state-value 1 1 120 1

My requirement is to capture the stateValue in my Linux machine(ubuntu) whenever the state changes its value.

If i use the chip-tool in the interactive start mode, then I cannot get the value outside the chip tool.

If I use the chp-tool in single command mode, once the tool exits, i can get the stateValue.

So, looking forward for a solution that notifies me on this value change.

The  use case is as below.

I have a contact sensor. I need to capture the stateValue whenever it changes.

I looked at the piece of code you posted above, but not sure how/where to implement that.

Can you please help?

[sigitas]

Hi Benny Nestler  topraveenpaul ,

I've just put some matter client draft to github:
https://github.com/sigidagi/light-switch-client

just take a look at the code...

Have a nice day.

Sigitas

[topraveenpaul]

Hi  sigitas ,

Thank you very much for your quick response. I will take a look and ask you if i have any question.

You have a nice day too.

topraveenpaul