How to configure GATT server in NRF app to test CTS example

Question

Hello, I read the instructions here for using the Nordic NRF Connect app for testing the CTS example: https://devzone.nordicsemi.com/f/nordic-q-a/53382/implementing-current-time-service-example 
 However, I do not see an option in the app for configuring the GATT server as described. I have an iPhone running iOS 13.6. I am using a Rigado BMD-340 Dev Kit with NRF52840 for running the CTS example. I have the most updated version of the NRF app. 
 This is a screenshot of what I see when I connect via the NRF Connect app:

As you can see from this screenshot, CTS discovery is not successful - no event seems to be triggered:

Question 1: How do I configure the GATT server on the NRF app to make my phone a Current Time server? 
 Question 2: How does the current time service get called? In the second screenshot (see references in left sidebar), it is evident that the event handler is never explicitly called. So how is an event generated? Let's say that a current time server is properly set up on the app. What does the client (NRF device) have to do to discover the Current Time Server, or to request a Current Time reading from the server? 
 Thanks!

Einar Thorsrud · Accepted Answer

Hi, 
 nordev said: Do you mean that these have to be added on the phone side in the NRF app, or on the firmware side? If the former, how do you add a service and characteristic in the app -- I did not see an option to do so... 
 You are right, I was writing too fast. That is only available on the Android version. So you have to use nRF Connect for desktop or nRF Connect for Android to do this test. 
 nordev said: Do you mean that the CTS instance and anything else registered as an observer each gets ALL the BLE events that occur and has to filter internally which events are relevant / can be handled by itself? 
 Yes, that is how it is done. 
 nordev said: Does it handle all BLE events, or only events associated with services? 
 The service implementation only handles what it cares about and ignore other events. 
 nordev said: If my previous statement is true, does that mean ble_cts_c_current_time_read() passes an event to the db discovery module? 
 No. The discovery module is used for service discovery, and no longer used when that is done. ble_cts_c_current_time_read() is implemented in the CTS client implementation (components\ble\ble_services\ble_cts_c\ble_cts_c.c), and that just makes a GATTC read operation. That is queued and handled by the SoftDevice, which will generate an event when the read is completed. If you look more in ble_cts_c.c, you will see the ble_cts_c_on_ble_evt() handler which handled events, and it calls current_time_read() do process this before it calls the applications event handler in the end. That is where you see this in your application. In the example, the event handler is on_cts_c_evt() in the main., and that is where you read it.

How to configure GATT server in NRF app to test CTS example

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