Importance and usage of ble primary service 'service_gap' ?

[nidhintomy]

In every ble gatt data base we can see these primary services in gatt_db.h file

1. service_gatt

2.service_gap 

I searched for references in project, but don't find anything related to these services.

Can anyone help me by share your knowledge,Please tell us about the importance and usage of these services.

Thanks

nidhintomy

[EduardoZamora]

Hello Nidhin,

The GAP Service must be present on any GATT Database. It has the Service UUID equal to 0x1800 and contains three read-only Characteristics about the device: Device Name, Appearance, and Peripheral Preferred Connections Parameters.

The GATT Service, with Service UUID equals to 0x1801, can be used to inform connected devices about changes made to the structure of services and characteristics.

You can find more information about these Services in the Bluetooth Low Energy Application Developer's Guide (specific SDK folder > docs > wireless > Bluetooth) and in Bluetooth Core Specification, Vol. 3, Part C: Generic Access Profile; and Part G: Generic Attribute Profile (GATT).

Regards,
Eduardo.

[nidhintomy]

Hi @EduardoZamora 

But i didn't find where these sevices getting used. I can see other services getting used in project files.

Can you tell me where these services used in BLE sample examples. I am using KW36 'temp_sens' sample example as a reference.

Best Regards,

Nidhin

[EduardoZamora · Accepted solution]

Hello,

GATT and GAP Services are handled by the Bluetooth stack library. Please, take a look at the Bluetooth Low Energy Developer's Guide, Chapter 4: Generic Access Profile (GAP); and Chapter 5: Generic Attribute Profile (GATT).

Regards,
Eduardo.

[nidhintomy]

Hi @EduardoZamora 

I read Chapter 4: Generic Access Profile (GAP); and Chapter 5: Generic Attribute Profile (GATT).

But didn't find any reference that BLE Stack Library handles the GATT and GAP Services.

I can build and debug the sample example without GATT and GAP Services. If BLE Stack Library handles the services, why i didn't get an error ?

Can you please clarify on this ?

Best Regards,

Nidhin

[EduardoZamora]

Hello, 

GAP service manages connections, security and bonded devices; GATT service is intended to discover services and characteristics and transferring data between devices. Any modification or exclusion of these services may cause an unexpected behavior depending on your application.

Source code for our BLE stack is not publicly available. Modification of the available BLE Stack is limited to the files and code outside pre-compiled, encrypted libraries.

If the functionality of the stack is not suited for the needs of the prototype you're developing, and the parts you want to modify are not accessible, you would need to develop a custom implementation, but this is really not recommended or encouraged, as for custom implementations, support is limited.

I apologize for any inconvenience this might cause you.

Regards.
Eduardo.

[nidhintomy]

Hi @EduardoZamora 

Thanks for your support.

These informations are very useful.

Best Regards,                                                                                                                                                         Nidhin