how to use standard and custom service uuids together?

[Hugo Habicht]

Hi,

I am having problems with the ble_advertising_int() function. It returns a return code of 12 (NRF_ERROR_DATA_SIZE) which is returned by ble_advertising_init() -> ble_advdata_encode() -> name_encode()

This only happens when I use two standard services and one custom service:

static ble_uuid_t m_adv_uuids[] =       // universally unique service ids
{
    {BLE_UUID_DEVICE_INFORMATION_SERVICE, BLE_UUID_TYPE_BLE              },
    {BLE_UUID_BATTERY_SERVICE,            BLE_UUID_TYPE_BLE              },
    {BLE_UUID_CUSTOM_SERVICE,             BLE_UUID_TYPE_VENDOR_BEGIN     },
};

When I remove the custom services everything works fine, also when I have only the custom service.

So how can I use standard and custom services in advertising together?

Kind Regards,

[Sigurd]

Hi,

An advertising packet can consist of no more than 31 bytes. Try placing the BLE_UUID_CUSTOM_SERVICE in the scan response packet instead. Take a look at e.g. the ble_app_uart example to see how it's done there.

[Hugo Habicht]

Hi,

well, 31 bytes is not a lot, really, particularly considering forced 16 bytes for a custom service uuid.

Isn't the purpose of the advertising packet to show all available services of the device?

Kind Regards,

[Sigurd]

Hugo Habicht said:

well, 31 bytes is not a lot, really, particularly considering forced 16 bytes for a custom service uuid.

This is defined by Bluetooth spec. A scanner will typically send a scan response request, and can get more information from the scan response packet. 

Hugo Habicht said:

Isn't the purpose of the advertising packet to show all available services of the device?

No, it does not have to include all services. When the central connects it will do a service discovery.