Only first BLE service discoverable on iOS

[Andreas]

Hello

I have got a working BLE application on a nRF51822 with the S120 as peripheral. In my application I added 3 user defined services to the softdevice. On Windows8 and Android I`m able to read/write all of these services. But on iOS I can only read/write the first service. It looks like only the first service is discovered by iOS. Is this because of the limited advertising package? In my advertising package I only add the first service. If so, why does it work on Android and iOS? How can I solve this problem?

For addition, here is my advertising_init function:

static uint32_t advertising_init(void){
uint32_t      err_code;
ble_advdata_t advdata;
	ble_advdata_t scanrsp;
	
	ble_uuid_t adv_uuids[] = {{BLE_UUID_DEVICE_SERVICE, GRL_DEV_SERVICE_UUID_TYPE}};

// Build and set advertising data.
memset(&advdata, 0, sizeof(advdata));
advdata.name_type             = BLE_ADVDATA_FULL_NAME;
	advdata.include_appearance      = true;
advdata.flags                 = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;
	
	memset(&scanrsp, 0, sizeof(scanrsp));
scanrsp.uuids_complete.uuid_cnt = sizeof(adv_uuids) / sizeof(adv_uuids[0]);
scanrsp.uuids_complete.p_uuids  = adv_uuids;
	
	ble_adv_modes_config_t options = {0};
options.ble_adv_fast_enabled  = BLE_ADV_FAST_ENABLED;
options.ble_adv_fast_interval = APP_ADV_INTERVAL;
options.ble_adv_fast_timeout  = APP_ADV_TIMEOUT_IN_SECONDS;

err_code = ble_advertising_init(&advdata, &scanrsp, &options, on_adv_evt, NULL);
APP_ERROR_CHECK(err_code);
	return err_code;}

Regards, BTprogrammer

[RK]

Where's your iOS code to do service discovery after you've connected to the peripheral?

[Andreas]

Hello, The iOS application is developed by an external partner. Therefor they use the Xamarin environment. Do you have an example what procedure we have to use on the iOS side to get all services? Regards, BTprogrammer

[Hung Bui]

@BTprogrammer: You can try to test using third party universal BLE tool app, such as LightBlue to see if it can fully discover your att table.

[Andreas]

Hello HungBui,

thank you for this note. I tried the lightblue App. On the start screen (lightblue scans for connectable devices) it shows me my device with only one service. But when I connect to the device, I can also read/write the UUID`s of my second Service. So it seems that there is a problem on the application side!? Regards!

[Hung Bui]

On the start screen, Lightblue will show the service UUID that included inside the advertising packet. In you code, I can see only GRL_DEV_SERVICE_UUID_TYPE included.

A central device would not be able to know what inside the attribute table without performing a service discovery after the connection is established.

I suspect that your application only look for the Service that it finds in the advertising packet, no service discovery was performed.