How the phone got the data from Nordic

[kai19960504]

Hi All,

SDK => v17.1.0

IDE => Segger

Project => ble_app_bps

I use LightBlue to connect my board,and going down to the device information service I choose system ID like this.

And I will click read again that can show me like this.

My question is : How does Nordic pass the information to the phone?

Bestregards,

Kai

[Hung Bui]

Hi Kai, 

I'm not very familiar with the LightBlue app. Please try again using nRF Connect for Mobile app. 

I assume you are asking how the LightBlue app would detect the Nordic Semiconductor field in Manufacturer data. It's because the Manufacturer data starts with a 2 byte company ID. If the device use our Nordic Semiconductor ID 0x0059. The phone will automatically detect the name. The list is here.

[kai19960504]

Hi Hung,

I just want to know which code of the sample code communicates with the mobile app.

[Hung Bui]

Hi Kai, 
The information about manufacturer name is provided inside services_init(). It's the device information service (dis), please have a look at the ble_dis_init() function. 

The softdevice will handle the communication between the phone and the nRF52 chip. If there is a read command , the softdevice will send the information stored in the service. 

[kai19960504]

Hung Bui said:

the softdevice will send the information stored in the service.

Hi Hung,

This is my problem, how is it sent?

[Hung Bui]

I would suggest you to study how BLE works first. Have a look here: https://www.youtube.com/watch?v=5TxUnbsHsR8&ab_channel=NordicSemiconductor

Note that a read request is handled by the softdevice automatically, you don't have to do anything in the application. 

[kai19960504]

Hi Hung,

I have else question that where is the data put let phone to read

[Hung Bui]

Hi Kai, 
The data is stored in the softdevice when you declare the characteristic. 
If you want to update the data you call sd_ble_gatts_value_set() or you can call sd_ble_gatts_hvx() to not only update the characteristic value but also send a notification/indication to the phone. 
Please study the example provided in the SDK.