I am programming BLE with the nRF52840-DK. [Toolchain Manager: v1.3.0, IDE: Visual Studio Code (VSCode), SDK: ncs v2.6.0, window11 pro]
My issue is that even when using the same 'NUS_central' code, the results of set_security and pairing vary depending on the hardware (nRF52840 DK).
[The command used is as follows: err = bt_conn_set_security(conn, BT_SECURITY_L2);"]
There are 3 case:
- 'Pairing' success, '
set_security'success (I couldn't save the debugging results.) - 'Pairing' failure, '
set_security'success - 'Pairing' failure, '
set_security'failure
The problem with the third scenario is that NUS doesn't function properly. Could you advise on the cause and potential solutions for this?
<case2, bluetooth working O: below is log debugging Regarding nRF52840-dK1 >
[00:00:09.425,018] <inf> cho: <<< scan_connecting >>>>
[00:00:09.522,491] <inf> cho: connected - Set_Security >>> err:0
[00:00:09.529,388] <inf> cho: connected - bt_conn_le_param_update (err 0)
[00:00:09.536,865] <inf> cho: connected - PHY >>> err:0
[00:00:09.542,755] <inf> cho: connected - data_length >>> err:0
[00:00:09.549,041] <inf> cho: connected - SCAN_STOP (err -120)
[00:00:09.555,297] <inf> cho: connected - GET_INFO >>> err:0
[00:00:09.561,370] <inf> cho: connected - Conn. interval is 40 units
[00:00:09.673,797] <err> bt_smp: pairing failed (peer reason 0x3)
[00:00:09.680,633] <inf> cho: CALLBACK - Security change failed: 4
[00:00:09.687,286] <inf> cho: gatt_discover - GATT_dm_start: 0
[00:00:09.693,572] <inf> cho: CALLBACK - Pairing failed conn: E0:2D:55:2C:95:E1 (random), reason 4
[00:00:09.874,114] <inf> cho: CALLBACK - Connection parameters updated. >> interval: 48, latency: 0, timeout: 400
[00:00:10.163,787] <inf> cho: CALLBACK - LE data len updated: TX (len: 251 time: 2120) RX (len: 251 time: 2120)
[00:00:10.763,214] <inf> cho: CALLBACK - LE PHY updated: TX PHY LE 2M, RX PHY LE 2M
[00:00:10.771,606] <inf> cho: CALLBACK - Service discovery completed
[00:00:10.778,533] <inf> cho: discovery_complete - MTU exchange pending
[00:00:11.003,662] <inf> cho: CALLBACK - MTU exchange done
<case3, bluetooth working X: below is log debugging Regarding nRF52840-dK2 >
[00:00:04.812,042] <inf> cho: main - scan_init>> 0
[00:00:04.817,199] <inf> cho: bt_nus_client_init >>> err:0
[00:00:04.823,120] <inf> cho: main - nus_client_init>> 0
[00:00:04.829,833] <inf> cho: main - bt_scan_start>> 0
[00:00:04.897,552] <inf> cho: Filters matched. Address: E0:2D:55:2C:95:E1 (random) connectable: 0
[00:00:04.908,508] <inf> cho: <<< scan_connecting >>>>
[00:00:05.000,091] <inf> cho: connected - Set_Security >>> err:-12
[00:00:05.007,049] <inf> cho: connected - bt_conn_le_param_update (err 0)
[00:00:05.014,526] <inf> cho: connected - PHY >>> err:0
[00:00:05.020,416] <inf> cho: connected - data_length >>> err:0
[00:00:05.026,702] <inf> cho: connected - SCAN_STOP (err -120)
[00:00:05.032,958] <inf> cho: connected - GET_INFO >>> err:0
[00:00:05.039,031] <inf> cho: connected - Conn. interval is 40 units
[00:00:05.351,531] <inf> cho: CALLBACK - Connection parameters updated. >> interval: 48, latency: 0, timeout: 400
[00:00:05.641,601] <inf> cho: CALLBACK - LE data len updated: TX (len: 251 time: 2120) RX (len: 251 time: 2120)
[00:00:06.241,027] <inf> cho: CALLBACK - LE PHY updated: TX PHY LE 2M, RX PHY LE 2M
below is connected callback function code:
static void connected(struct bt_conn *conn, uint8_t conn_err){
char addr[BT_ADDR_LE_STR_LEN];
int err;
struct bt_conn_info info = {0};
bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr));
if(conn_err){
LOG_INF("Failed to connect to %s (%d)", addr, conn_err);
if (default_conn == conn) {
bt_conn_unref(default_conn);
default_conn = NULL;
err = bt_scan_start(BT_SCAN_TYPE_SCAN_ACTIVE);
LOG_INF("Scanning failed to start (err %d)",err);
}
return;
}
default_conn = bt_conn_ref(conn);
// err = bt_conn_get_info(conn, &info);
// LOG_INF("connected - GET_INFO >>> err:%d", err);
// LOG_INF("connected - Connected as %s", info.role == BT_CONN_ROLE_CENTRAL ? "central" : "peripheral");
// LOG_INF("connected - Conn. interval is %u units", info.le.interval);
err = bt_conn_set_security(conn, BT_SECURITY_L2);
LOG_INF("connected - Set_Security >>> err:%d", err);
err = bt_conn_le_param_update(conn, conn_param2);
LOG_INF("connected - bt_conn_le_param_update (err %d)", err);
err = bt_conn_le_phy_update(conn, BT_CONN_LE_PHY_PARAM_2M);
LOG_INF("connected - PHY >>> err:%d", err);
err = bt_conn_le_data_len_update(conn, BT_LE_DATA_LEN_PARAM_MAX);
LOG_INF("connected - data_length >>> err:%d", err);
err = bt_scan_stop(); // success: 0 or -120
LOG_INF("connected - SCAN_STOP (err %d)", err);
err = bt_conn_get_info(conn, &info);
LOG_INF("connected - GET_INFO >>> err:%d", err);
LOG_INF("connected - Conn. interval is %u units", info.le.interval);
}
static struct bt_conn_cb conn_callbacks = {
.connected = connected,
.disconnected = disconnected,
.security_changed = security_changed,
.le_param_updated = le_param_updated,
.le_data_len_updated = le_data_length_updated,
.le_phy_updated = le_phy_updated,
.le_param_req = le_param_req,
};
