BLE_ERROR_GATTS_SYS_ATTR_MISSING

[VadimSavchuk]

Hi. I have a problem with HID keyboard example. Function sd_ble_gatts_hvx returns 0x00003401. I know that it's means BLE_ERROR_GATTS_SYS_ATTR_MISSING. But how and where I must set attributes or enable notification. I know that I must restore attributes from storage. But how? I read many posts about this but I can not to fix this problem. Please help me. Thank you in advance.

BLE_ERROR_GATTS_SYS_ATTR_MISSING does not handle

[Hung Bui]

If you haven't bonded with the device before you need to call sd_ble_gatts_sys_attr_set(NULL) to initialize the CCCD value as shown in the description of the sd_ble_gatts_hvx() function.

if you have bonded and stored system attribute , then you need to call sd_ble_gatts_sys_attr_set() with the attribute value you have stored.

If you use our ble_app_hid_keyboard, you will find how we handled it in gatts_cache_manager.c

[VadimSavchuk]

Thank you. But in which place i must call sd_ble_gatts_sys_attr_set( NULL )? The event BLE_GATTS_EVT_SYS_ATTR_MISSING doesn't come. And I tried to use peer manager instead device manager. I had the same result(

[Hung Bui]

If you get no service discovery then the BLE_GATTS_EVT_SYS_ATTR_MISSING won't come.

You can try to call sd_ble_gatts_sys_attr_set(NULL) when you receive _CONNECTED event.

If you test with our ble_app_hid_keyboard do you see the same problem ?

[VadimSavchuk]

Yes, It is. I use your ble_app_hid_keyboard. The same problem. I tried to call sd_ble_gatts_sys_attr_set(NULL) in the _CONNECTED event. But I see the same problem. I have not many experience with bluetooth. So maybe I somewhere I made a mistake. But firstly all works fine. After reconnect I see this problem

[VadimSavchuk]

I don't know how and where I must restore ATTR data