NRF52 db discovery event has all characteristic uuids 0

RE: NRF52 db discovery event has all characteristic uuids 0

Vidar Berg — Wed, 08 Aug 2018 08:19:39 GMT

You're right, the 2nd parameter is an output. I just assumed it was input argument. Sorry for the confusion.

I did not manage to reproduce the issues. I used the pre-compiled bootloader hex in sdk 13 and modified the uart central example to discover the DFU service. So I'm not sure what the problem is. Suggest that you do a comparison of your implementation with attached main.c and see if you can spot any relevant differences (verify that we are using same UUIDs etc).

<info> app: Connected to target
<info> app: 0: uuid: 0002 cccd:0000. value:0010

<info> app: 1: uuid: 0001 cccd:0013. value:0012

devzone.nordicsemi.com/.../main.c

RE: NRF52 db discovery event has all characteristic uuids 0

ryan — Tue, 07 Aug 2018 17:01:26 GMT

I know that I'm calling ble_db_discovery_start only once... otherwise my output would display "<info> app: uuid vs add returned: 0/0000" more than once, which it does not.

regarding the uuid type, sd_ble_uuid_vs_add()'s 2nd parameter is and output, storing the uuid type into the unit8_t that is passed by adress on your code's line 20. so your assignment in line 17 is without impact per the documentation. -- in my implementation, on line 4 i do the exact same thing as your reference so i'm not sure why you're asking about it... can you elaborate a bit more on your question?

ble_uuid_t    dfu_service_uuid = { .uuid    = DFU_SERVICE_UUID_16bit };     
                                                                                 
uint32_t err_code = sd_ble_uuid_vs_add(&base_uuid, &dfu_service_uuid.type);

can you confirm the SDK version of the peripheral you were connecting with?

RE: NRF52 db discovery event has all characteristic uuids 0

Vidar Berg — Tue, 07 Aug 2018 10:54:07 GMT

Hi,

Noticed that you call ble_db_discovery_start() after ble_db_discovery_evt_register(). Please try to only call ble_db_discovery_start() from the BLE_GAP_EVT_CONNECTED to ensure that the service is discovered once.

I couldn't tell from the code snippets you provided, but did you set dfu_service_uuid.type to BLE_UUID_TYPE_BLE? I was unable to replicate this with the code below.

void dfu_c_init()
{
    uint32_t      err_code;
    ble_uuid_t    dfu_uuid;
    uint8_t       uuid_type = BLE_UUID_TYPE_VENDOR_BEGIN;
    
    /*Base UUIDs for DFU service characteristics*/
    ble_uuid128_t dfu_base_uuid = 
    {
        {
            0x50, 0xEA, 0xDA, 0x30, 0x88, 0x83, 0xB8, 0x9F,
            0x60, 0x4F, 0x15, 0xF3,  0x00, 0x00, 0xC9, 0x8E
        }
    };


    dfu_uuid.type = BLE_UUID_TYPE_BLE;
    dfu_uuid.uuid = 0xFE59;

    err_code = sd_ble_uuid_vs_add(&dfu_base_uuid, &uuid_type);
    APP_ERROR_CHECK(err_code);


    err_code = ble_db_discovery_evt_register(&dfu_uuid);
    APP_ERROR_CHECK(err_code);
}