Problem with nRF Connect for Android

[Davide]

Hello,

I'm working on a custom GATT service which has only one characteristic that support notification. The code has started from the ble_hrm service and it runs on a thingy (in parallel with all the other services the original thingy firmware has). With respect to the standard thingy firmware, in my application it is the thingy that connects as Central and the smartphone that acts as Peripheral.

When I enable the notification, the device start sending data, sd_ble_gatts_hvx returns NRF_SUCCESS and I get BLE_GATTS_EVT_HVN_TX_COMPLETE anyway on nRF Connect for Android (v 4.19.1) I cannot see the notification arriving. The strange thing is that, with an older version of nRF Connect for Android it worked and also with the desktop version it works. Moreover by porting the code to run on a PCA10040 again it works.

I have the impression that the nRF Connect somehow have problem when an unknown custom service is added to the Thingy GATT server.

Is this an expected behavior?

Thank you Davide.

[Hung Bui]

Hi Davide, 

 

A sniffer trace would verify if the notifications are actually sent over the air. 

When you mentioned porting the code to PCA10040, did you port the whole ATT table of the thingy ?

Have you tried with just one service and characteristic that you create (without the thingy's services)?

 

 

 

[Davide]

On the PCA10040 I just implemented my service, not the whole gatt server of the thingy.

I didn't try the Thingy with just one service, anyway it works with all services on nRF Connect for Windows. I think the error cannot be on the Thingy side, otherwise it wouldn't work on windows.

I'm quite sure the notifications are sent, because on an older version of nRF Connect for Android and on the last version of nRF Connect for windows everything works as expected. Notification are sent without any error and shown on the remote device.

Starting from this condition, if I open nRF Connect for Android (last version 4.19.1) it connects and it finds the charactersitic. When I write the CCCD I see in the log screen that the write operation reach the thingy device that starts sending notification. They are sent with no error on the nRF52832, but nothing is shown in nRF Connect.