Hello.
I'm trying to use a nrf52840 as a central device and connect to a gopro13. The connection works a certain number of times. But after a while (several days or maybe several connections), the connection fails. Other devices (phone, remote control) successfully connect to the GoPro. If I start the pairing process on the GoPro, the connection will be successful and will work for some time.
More details:
My device is based on Ebyte E73-2G4M08S1C module.
My device shematic:
Project code - https://github.com/Sergey1560/nrf52_gopro_zephyr
NRF Connect SDK v3.1.1
When I first connect to the GoPro, I select pairing mode on the camera. The connection is successful.
Do I need to save the connection settings separately afterward, or are they saved automatically?
At startup, I load the saved settings and display messages to monitor this:
err = bt_conn_auth_cb_register(&conn_auth_callbacks);
if (err) {
LOG_ERR("Failed to register authorization callbacks.");
return 0;
}
err = bt_conn_auth_info_cb_register(&conn_auth_info_callbacks);
if (err) {
LOG_ERR("Failed to register authorization info callbacks.\n");
return 0;
}
err = bt_enable(NULL);
if (err) {
LOG_ERR("Bluetooth init failed (err %d)", err);
return 0;
}
LOG_INF("Bluetooth initialized");
err=settings_load();
if(err != 0){
LOG_ERR("Settings load err: %d",err);
}else{
LOG_DBG("Settings load done");
}
scan_init();
err = scan_start();
if (err) {
return 0;
}
In the scan function, I check that there are saved connection settings to ignore other cameras that may be nearby:
static void try_add_address_filter(const struct bt_bond_info *info, void *user_data){
int err;
char addr[BT_ADDR_LE_STR_LEN];
uint8_t *filter_mode = user_data;
bt_addr_le_to_str(&info->addr, addr, sizeof(addr));
LOG_DBG("Saved bond found: %s",addr);
struct bt_conn *conn = bt_conn_lookup_addr_le(BT_ID_DEFAULT, &info->addr);
if (conn) {
bt_conn_unref(conn);
return;
}
err = bt_scan_filter_add(BT_SCAN_FILTER_TYPE_ADDR, &info->addr);
if (err) {
LOG_ERR("Address filter cannot be added (err %d): %s", err, addr);
return;
}
LOG_INF("Address filter added: %s", addr);
*filter_mode |= BT_SCAN_ADDR_FILTER;
}
static int scan_start(void){
int err;
uint8_t filter_mode = 0;
err = bt_scan_stop();
if (err) {
LOG_ERR("Failed to stop scanning (err %d)", err);
return err;
}
bt_scan_filter_remove_all();
bt_foreach_bond(BT_ID_DEFAULT, try_add_address_filter, &filter_mode);
if((filter_mode & BT_SCAN_ADDR_FILTER) == 0){
LOG_DBG("Saved bonds not found, filter by UUID");
filter_mode = BT_SCAN_UUID_FILTER;
err = bt_scan_filter_add(BT_SCAN_FILTER_TYPE_UUID, BT_UUID_GOPRO_SERVICE);
if (err) {
LOG_ERR("UUID filter cannot be added (err %d", err);
return err;
}
}
err = bt_scan_filter_enable(filter_mode, false);
if (err) {
LOG_ERR("Filters cannot be turned on (err %d)", err);
return err;
}
err = bt_scan_start(BT_SCAN_TYPE_SCAN_ACTIVE);
if (err) {
LOG_ERR("Scanning failed to start (err %d)", err);
return err;
}
led_idle_timer_start(1);
LOG_INF("Scan started");
return 0;
}
Debug output when connection fails:
<dbg> can_mcp2515: mcp2515_init: Presc: 2, BS1: 7, BS2: 2
[00:00:00.001,007] <dbg> can_mcp2515: mcp2515_init: Sample-point err : 0
*** Booting nRF Connect SDK v3.1.1-e2a97fe2578a ***
*** Using Zephyr OS v4.1.99-ff8f0c579eeb ***
[00:00:14.203,155] <dbg> gopro_main: clocks_start: HF clock started
[00:00:14.203,216] <inf> gopro_leds: Set up LED at GPIO_0 pin 28
[00:00:14.203,247] <inf> gopro_leds: Set up LED at GPIO_1 pin 11
[00:00:14.203,369] <dbg> canbus_gopro: canbus_init: CAN device ready
[00:00:14.203,369] <dbg> canbus_gopro: canbus_init: MODE NORMAL Enabled.
[00:00:14.204,406] <inf> canbus_gopro: CAN Start
[00:00:14.204,467] <inf> canbus_gopro: CAN BUS init done
[00:00:14.212,280] <inf> fs_nvs: 2 Sectors of 4096 bytes
[00:00:14.212,280] <inf> fs_nvs: alloc wra: 0, fb8
[00:00:14.212,310] <inf> fs_nvs: data wra: 0, 8c
[00:00:14.212,493] <inf> bt_sdc_hci_driver: SoftDevice Controller build revision:
fc de 41 eb a2 d1 42 24 00 b5 f8 57 9f ac 9d 9e |..A...B$ ...W....
aa c9 b4 34 |...4
[00:00:14.216,888] <inf> bt_hci_core: HW Platform: Nordic Semiconductor (0x0002)
[00:00:14.216,949] <inf> bt_hci_core: HW Variant: nRF52x (0x0002)
[00:00:14.216,979] <inf> bt_hci_core: Firmware: Standard Bluetooth controller (0x00) Version 252.16862 Build 1121034987
[00:00:14.217,407] <inf> bt_hci_core: No ID address. App must call settings_load()
[00:00:14.217,407] <inf> gopro_discovery: Bluetooth initialized
[00:00:14.218,322] <inf> bt_hci_core: HCI transport: SDC
[00:00:14.218,444] <inf> bt_hci_core: Identity: F6:4F:7D:39:A8:A5 (random)
[00:00:14.218,475] <inf> bt_hci_core: HCI: version 6.1 (0x0f) revision 0x1069, manufacturer 0x0059
[00:00:14.218,505] <inf> bt_hci_core: LMP: version 6.1 (0x0f) subver 0x1069
[00:00:14.220,245] <dbg> gopro_discovery: gopro_bt_start: Settings load done
[00:00:14.220,275] <inf> gopro_discovery: Scan module initialized
[00:00:14.220,397] <dbg> gopro_discovery: try_add_address_filter: Saved bond found: C6:D9:69:8A:22:91 (random)
[00:00:14.220,520] <inf> gopro_discovery: Address filter added: C6:D9:69:8A:22:91 (random)
[00:00:14.221,649] <inf> gopro_discovery: Scan started
[00:00:14.221,801] <dbg> canbus_gopro: isotp_rx_thread: Bind ISO-TP
[00:00:14.221,832] <dbg> canbus_gopro: isotp_rx_thread: Semaphore lock 0
[00:00:14.289,154] <dbg> gopro_discovery: scan_filter_match: Filters matched. Address: C6:D9:69:8A:22:91 (random) connectable: 1
[00:00:14.289,245] <dbg> gopro_c: gopro_client_set_sate: Set GoPro state: 2
[00:00:14.289,367] <dbg> gopro_discovery: eir_found: Camera ON, connecting
[00:00:14.354,980] <err> canbus_gopro: Can send timeout
[00:00:14.404,632] <err> canbus_gopro: CAN Sending failed [-11]
[00:00:14.451,782] <inf> gopro_discovery: Connected: C6:D9:69:8A:22:91 (random)
[00:00:14.451,934] <inf> gopro_discovery: Change security
[00:00:14.452,545] <err> gopro_discovery: Stop LE scan failed (err 0)
[00:00:14.702,911] <wrn> bt_conn: conn 0x200037b0 failed to establish. RF noise?
[00:00:14.703,308] <wrn> gopro_discovery: Security failed: C6:D9:69:8A:22:91 (random) level 1 err 9 BT_SECURITY_ERR_UNSPECIFIED
[00:00:14.703,399] <wrn> gopro_discovery: MTU exchange failed (err 14)
[00:00:14.703,613] <inf> gopro_discovery: Disconnected: C6:D9:69:8A:22:91 (random), reason 0x3e
[00:00:14.703,735] <dbg> gopro_discovery: disconnected: Pause for 3 sec
[00:00:17.703,979] <dbg> gopro_discovery: scan_work_handler: Scan start
[00:00:17.704,132] <dbg> gopro_discovery: try_add_address_filter: Saved bond found: C6:D9:69:8A:22:91 (random)
[00:00:17.704,223] <inf> gopro_discovery: Address filter added: C6:D9:69:8A:22:91 (random)
[00:00:17.705,261] <inf> gopro_discovery: Scan started
[00:00:17.773,529] <dbg> gopro_discovery: eir_found: Camera ON, connecting
[00:00:17.933,135] <inf> gopro_discovery: Connected: C6:D9:69:8A:22:91 (random)
[00:00:17.933,288] <inf> gopro_discovery: Change security
[00:00:17.933,898] <err> gopro_discovery: Stop LE scan failed (err 0)
[00:00:18.184,265] <wrn> bt_conn: conn 0x200037b0 failed to establish. RF noise?
[00:00:18.184,661] <wrn> gopro_discovery: Security failed: C6:D9:69:8A:22:91 (random) level 1 err 9 BT_SECURITY_ERR_UNSPECIFIED
[00:00:18.184,753] <wrn> gopro_discovery: MTU exchange failed (err 14)
[00:00:18.184,967] <inf> gopro_discovery: Disconnected: C6:D9:69:8A:22:91 (random), reason 0x3e
[00:00:18.185,089] <dbg> gopro_discovery: disconnected: Pause for 3 sec
[00:00:21.185,333] <dbg> gopro_discovery: scan_work_handler: Scan start
[00:00:21.185,485] <dbg> gopro_discovery: try_add_address_filter: Saved bond found: C6:D9:69:8A:22:91 (random)
[00:00:21.185,577] <inf> gopro_discovery: Address filter added: C6:D9:69:8A:22:91 (random)
[00:00:21.186,553] <inf> gopro_discovery: Scan started
[00:00:21.551,940] <dbg> gopro_discovery: eir_found: Camera ON, connecting
[00:00:21.709,045] <inf> gopro_discovery: Connected: C6:D9:69:8A:22:91 (random)
[00:00:21.709,197] <inf> gopro_discovery: Change security
[00:00:21.709,777] <err> gopro_discovery: Stop LE scan failed (err 0)
[00:00:21.960,174] <wrn> bt_conn: conn 0x200037b0 failed to establish. RF noise?
[00:00:21.960,571] <wrn> gopro_discovery: Security failed: C6:D9:69:8A:22:91 (random) level 1 err 9 BT_SECURITY_ERR_UNSPECIFIED
[00:00:21.960,662] <wrn> gopro_discovery: MTU exchange failed (err 14)
[00:00:21.960,845] <inf> gopro_discovery: Disconnected: C6:D9:69:8A:22:91 (random), reason 0x3e
[00:00:21.960,998] <dbg> gopro_discovery: disconnected: Pause for 3 sec
[00:00:24.961,242] <dbg> gopro_discovery: scan_work_handler: Scan start
[00:00:24.961,395] <dbg> gopro_discovery: try_add_address_filter: Saved bond found: C6:D9:69:8A:22:91 (random)
[00:00:24.961,486] <inf> gopro_discovery: Address filter added: C6:D9:69:8A:22:91 (random)
[00:00:24.962,463] <inf> gopro_discovery: Scan started
[00:00:25.032,592] <dbg> gopro_discovery: eir_found: Camera ON, connecting
[00:00:25.190,948] <inf> gopro_discovery: Connected: C6:D9:69:8A:22:91 (random)
[00:00:25.191,131] <inf> gopro_discovery: Change security
[00:00:25.191,711] <err> gopro_discovery: Stop LE scan failed (err 0)
[00:00:25.442,077] <wrn> bt_conn: conn 0x200037b0 failed to establish. RF noise?
[00:00:25.442,474] <wrn> gopro_discovery: Security failed: C6:D9:69:8A:22:91 (random) level 1 err 9 BT_SECURITY_ERR_UNSPECIFIED
[00:00:25.442,565] <wrn> gopro_discovery: MTU exchange failed (err 14)
[00:00:25.442,779] <inf> gopro_discovery: Disconnected: C6:D9:69:8A:22:91 (random), reason 0x3e
[00:00:14.220,245] - settings loaded successfully
[00:00:14.220,397] - Saved bond found: C6:D9:69:8A:22:91 (random)
The address is correct, this is my camera. I think we can say that the settings were saved and loaded successfully.
The connection to the camera only starts if the camera is turned on. This is indicated in the advertising ( eir_found function).
To connect, I call the bt_conn_le_create function. In the callback, I display a message that the connection has been established and try to change security level to BT_SECURITY_L2:
static void connected(struct bt_conn *conn, uint8_t conn_err){
static struct bt_gatt_exchange_params exchange_params;
char addr[BT_ADDR_LE_STR_LEN];
int err;
bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr));
if (conn_err) {
LOG_INF("Failed to connect to %s, 0x%02x %s", addr, conn_err, bt_hci_err_to_str(conn_err));
if (default_conn == conn) {
bt_conn_unref(default_conn);
default_conn = NULL;
(void)k_work_submit(&scan_work);
}
return;
}
LOG_INF("Connected: %s", addr);
led_idle_timer_start(0);
gopro_led_mode_set(LED_NUM_REC,LED_MODE_OFF);
exchange_params.func = exchange_func;
err = bt_gatt_exchange_mtu(conn, &exchange_params);
if (err) {
LOG_WRN("MTU exchange failed (err %d)", err);
}
LOG_INF("Change security");
err = bt_conn_set_security(conn, BT_SECURITY_L2);
if (err) {
LOG_WRN("Failed to set security: %d", err);
gatt_discover(conn);
}
err = bt_scan_stop();
if ((!err) && (err != -EALREADY)) {
LOG_ERR("Stop LE scan failed (err %d)", err);
}
}
In debug output:
[00:00:14.451,782] <inf> gopro_discovery: Connected: C6:D9:69:8A:22:91 (random)
[00:00:14.451,934] <inf> gopro_discovery: Change security
[00:00:14.452,545] <err> gopro_discovery: Stop LE scan failed (err 0)
[00:00:14.702,911] <wrn> bt_conn: conn 0x200037b0 failed to establish. RF noise?
[00:00:14.703,308] <wrn> gopro_discovery: Security failed: C6:D9:69:8A:22:91 (random) level 1 err 9 BT_SECURITY_ERR_UNSPECIFIED
If I enter pairing mode on the GoPro, the connection will be successful. And it will be successful many times, even if I disconnect the power. It will connect successfully every time. But after a certain number of connections, or maybe even days, it stops connecting. And it won't connect again, no matter how many times I try, until I enter pairing mode.
By the schematic, my module doesn't have an external 32kHz crystal. Therefore, in the board settings ( https://github.com/Sergey1560/nrf52_gopro_zephyr/blob/master/boards/vend/goprocan_nrf52840/goprocan_nrf52840_defconfig ) , I use:
CONFIG_CLOCK_CONTROL_NRF_K32SRC_SYNTH=y
CONFIG_CLOCK_CONTROL_NRF_K32SRC_XTAL=n
Full device tree:
Wireshark log, when connection fail:
What could be the cause of the problem?
