"Just works" Level 2 security

RE: "Just works" Level 2 security

Pmr — Thu, 12 Oct 2023 13:17:57 GMT

Problem solved, i forgot BT_GATT_CCC(ccc_cfg_changed, BT_GATT_PERM_READ_ENCRYPT | BT_GATT_PERM_WRITE_ENCRYPT ), ); I only had the READ part, so when i reconnected, it apparently disconnected me..

RE: "Just works" Level 2 security

Pmr — Thu, 12 Oct 2023 10:12:29 GMT

I don't have a dev kit I can use for sniffing.

If i remove all the BT_GATT_PERM_WRITE/READ_ENCRYPT in my GATT services, and change them to just READ/WRITE, then it reconnects without any issues everytime.

RE: "Just works" Level 2 security

dejans — Thu, 12 Oct 2023 10:08:04 GMT

Hi,

You could try to avoid bonding with Android.
Additionally, you could try to use nRF sniffer to identify what might be wrong.

Best regards,
Dejan

RE: "Just works" Level 2 security

Pmr — Thu, 12 Oct 2023 09:08:24 GMT

I tried to remove the bt_conn_set_security() and decorate my gatt services like this:

BT_GATT_SERVICE_DEFINE(ble_data_service,
BT_GATT_PRIMARY_SERVICE(&ble_data_service_uuid),
BT_GATT_CHARACTERISTIC(&ble_data_char_uuid.uuid, BT_GATT_CHRC_READ | BT_GATT_CHRC_NOTIFY, BT_GATT_PERM_READ_ENCRYPT, ble_data_char_read, NULL, &ads1298_adv_data),
BT_GATT_CCC(ccc_cfg_changed, BT_GATT_PERM_WRITE_ENCRYPT), );

This also prompts the user for a pairing the first time and successfully start reading data, but after a reconnect it keeps getting disconnected, and after a lot of tries it succeeds.

RE: "Just works" Level 2 security

Pmr — Wed, 11 Oct 2023 15:31:47 GMT

I have tried with a Huawei p30 pro android 10 and a Xiaomi android 11. If I disable all the security, then there is no issue.

I tested with an iphone 10. With no issues.

It's a custom device we use to gather emg data.

The example in my video was just to show the issue, the same happens when we pair through our Xamarin app. Or use the nrf connect application.

RE: "Just works" Level 2 security

dejans — Wed, 11 Oct 2023 15:15:27 GMT

Hi,

Which mobile phone (type and Android version) do you use? Which device do you use on the other side?

Have you tried using nRF Connect for Mobile application instead of Device Manager?

Which other devices have you tried apart from mentioned Android device?

Best regards,
Dejan

RE: "Just works" Level 2 security

Pmr — Wed, 11 Oct 2023 12:12:18 GMT

devzone.nordicsemi.com/.../SVID_5F00_20231011_5F00_140206_5F00_1.mp4

Here is a video showing the issue (again this seems to only be on android phones)