BLE Mesh Model for user data transfer

[selvam]

Hi Nordic team,

We have planned to use nRF5340 based BLE mesh device which is interface with sensor 

We would like to transfer customized user data from one node to another node at different location via BLE mesh network. 

Shall we use Generic On/Off model for this user data transfer from one node to another node through BLE mesh?

If yes, what is the maximum possible size of user data to transfer?

Shall we use the "Mesh light (as Server) " and Mesh light switch (As client) sample for this use case?

Thanks

Selvam

[Hung Bui]

Hi Selvam, 

If you are planning to transmit customized data, I would suggest to create your own model instead of using the Generic on/off model. The generic model from Bluetooth SIG is defined in the spec and can't be modified as your need. 
Note that when you define your own model, you need to follow the spec and tie your model to your company ID. Please check the bluetooth mesh spec on this. 
An example that you can have a look is the \nrf\samples\bluetooth\mesh\chat in the NCS SDK v1.5.0. 

In the example we defined a vendor specific model for sending chat message between nodes. In the implementation we use chat clients on all node, but if you want client-server communication, you can also define your server model based on how we define the client. 

[selvam]

Hi Hung Bui,

Thanks for the inputs on selecting BLE mesh model. 

We will refer the given example and follow the testing procedure as per in the link Bluetooth: Mesh chat — nRF Connect SDK 1.5.0 documentation (nordicsemi.com)..

We will revert back once we tried .

Thanks

Selvam

[selvam]

Hi Hung Bui,

While loading the sample chat as below steps,

1. Connect nRF5340 DK and Load merged_CPUNET.hex through "nRF connect Programmer"

Close device in ""nRF connect Programmer"

2. In "Segger Embedded Studio", Connect J link and Click "Build and Debug" option. 

we are getting the below fail message in putty and there is no device name in "nRF mesh" mobile app

uart:~$ I: HW Platform: Nordic Semiconductor (0x0002)
I: HW Variant: nRF53x (0x0003)
I: Firmware: Standard Bluetooth controller (0x00) Version 229.40135 Build 486576601
I: No ID address. App must call settings_load()
Bluetooth initialized
>>> Bluetooth Mesh Chat sample <<<
uart:~$ W: ECC HCI commands not available
E: Failed to generate public key (-35)
Initializing mesh failed (err -35)

Please guide , is any steps we missed ?

It will helpful to proceed.

Thanks in Advance.

Thanks

Selvam

[Hung Bui]

Hi Selvam, 

Sorry for late response. We had Easter vacation last week. 

The log showed that there was an issue with the HCI interface. Could be an issue with the image on the netcore. Please made sure that it's the Zephyr controller used, not the Nordic's one. It's described here.

Have you managed to run other mesh examples ? For example the light_switch sample? 

[selvam]

No problem Hung Bui,

Hope you enjoyed the Easter Vacation. 

BTW, By configuring "CONFIG_BT_TINYCRYPT_ECC=y" able to do communication between nRF5340 DK boards through UART shell. 

It looks like TX and RX thread of Zephyr expecting the data from Shell and then do the BLE data handle.

But the need is to transfer the own data between two nRF5340 boards without shell typing. 

Please guide us to transfer the data without using shell.

Thanks

Selvam