sd_ble_gap_authenticate error 0x06 (NRF_ERROR_NOT_SUPPORTED)

[MC]

I want to bond with an peripheral, which has static passkey hardcoded in it. If I want to bond with it with MCP, I get an request for passkey, I can then bond and encrypt the connection with the peripheral, So far, so good. Then, I wanted to implement the same behavioural on my central, with S120 v2 and SDK 8.1.0. I wanted to use the function sd_ble_gap_authenticate to get BLE_GAP_EVT_AUTH_KEY_REQUEST response, so I could send the passkey to peripheral.

This is where I encountered a problem. My central connects to the peripheral and triggers bonding and encryption by calling sd_ble_gap_authenticate. Funcion returns error NRF_ERROR_NOT_SUPPORTED Why is that so? This error message isn't documented in SDK documentation as a valid error message.

I am calling the function with the following parameters:

ble_gap_sec_params_t security_params;
					
security_params.bond         = 1;
security_params.mitm         = 1;
security_params.io_caps      = BLE_GAP_IO_CAPS_KEYBOARD_ONLY;
security_params.oob          = 0;
security_params.min_key_size = 7;
security_params.max_key_size = 16;
security_params.kdist_periph.enc = 1;
security_params.kdist_periph.id  = 1;
					
err_code = sd_ble_gap_authenticate(conn_handle, &security_params);
APP_ERROR_CHECK(err_code);

I can't seem to find any documentation on this topic, maybe I'm calling authenticating function too early or at the wrong place?

[shibshab]

Have you turned off optimizations to ensure that you are reading the correct value? Here is description on ensuring that you are reading the correct values.

[MC]

Yes, optimizations are set to 0 and DEBUG is defined.

[Petter Myhre]

What if you do a memset(&security_params, 0, sizeof(security_params));?

[MC]

If I do memset, I stop getting "not supported" error, but another problem has emerged. Now I'm getting a hardfault a few seconds after I call authenticating function. One way to avoid harfault is to add central kdist params to the structure security_params.kdist_periph.sign = 0; security_params.kdist_central.enc = 1; security_params.kdist_central.id =1; security_params.kdist_central.sign = 0; But this causes authentication procedure to timeout after about 30s. So i would need some help debugging this new hardfault/timeout issue.

[MC]

It turned out, that hardfault was beng caused by wong array index in the code, so my above comment is obsolete. I still don't understand why "memset" worked though... But it solved my initial problem.