When android setValue on characteristics

[gary]

Hello, I am working on characteristics tutorial.(our service.c) And I succeeded in notifying characteristic from nordic to android. The methods I used to notify characteristic update are timer_handler and update_characteristic. ok. that's fine. However, I don't know how nordic is aware of characteristic changed, when android sets value. How can nordic know the change in its characteristics? Is there any event handler that controls my problem? If you let me know, I guess I can finally succeed in data transfer. (While searching on Google, I found that nus_data_handler is a solution, but I think it is not fit to my example. ) Thank you.

[Hung Bui]

Hi Gary,

You will receive BLE_GATTS_EVT_WRITE event in the application. You can find most of the BLE events and how thing should be handled by looking at the message sequence charts, for example here.

[gary]

thanks a lot. It helped me a lot. I have one more question. Then, is there any related examples so I can see the event handler? And I found that some people said the method for data receiving is nus_data_handler. Is this related to what I am looking for (characteristic write event)?

[Hung Bui]

Hi Gary, Yes you can have a look at the ble_app_uart example in our nRF5 SDK. You can find how we catch BLE_GATTS_EVT_WRITE event and then call the nus_data_handler() ( as the nus_init.data_handler ) to handle the event.

You can have a look at other examples as well, to get familiar with the peer manager library (not used in the ble_app_uart example).