OpenEarable · DennisMoschina · Nov 17, 2025 · Nov 17, 2025 · Nov 17, 2025 · Nov 17, 2025
diff --git a/.github/workflows/build_firmware.yaml b/.github/workflows/build_firmware.yaml
@@ -50,9 +50,9 @@ jobs:
 
       - name: Install Zephyr SDK
         run: |
-          wget -q https://github.com/zephyrproject-rtos/sdk-ng/releases/download/v0.16.4/zephyr-sdk-0.16.4_linux-x86_64_minimal.tar.xz
-          tar xf zephyr-sdk-0.16.4_linux-x86_64_minimal.tar.xz -C ~/
-          ~/zephyr-sdk-0.16.4/setup.sh -c -t arm-zephyr-eabi
+          wget -q https://github.com/zephyrproject-rtos/sdk-ng/releases/download/v0.17.0/zephyr-sdk-0.17.0_linux-x86_64_minimal.tar.xz
+          tar xf zephyr-sdk-0.17.0_linux-x86_64_minimal.tar.xz -C ~/
+          ~/zephyr-sdk-0.17.0/setup.sh -c -t arm-zephyr-eabi
 
       - name: Initialize Zephyr Workspace
         # Set up the Zephyr workspace and install the Python dependencies

diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -55,6 +55,7 @@ zephyr_library_include_directories(
     src/SD_Card/SDLogger
     src/SD_Card/Benchmark
     src/SD_Card/SD_Card_Manager
+    src/time_sync
 )
 
 zephyr_library_include_directories(app PRIVATE
@@ -74,6 +75,7 @@ add_subdirectory(src/SensorManager)
 add_subdirectory(src/SD_Card/SDLogger)
 add_subdirectory(src/SD_Card/Benchmark)
 add_subdirectory(src/SD_Card/SD_Card_Manager)
+add_subdirectory(src/time_sync)
 
 ## Cirrus Logic
 if (CONFIG_HW_CODEC_CIRRUS_LOGIC)

diff --git a/README.md b/README.md
@@ -2,7 +2,8 @@
 
 [OpenEarable](openearable.com) is the world's first fully open-source AI platform for ear-based sensing applications with true wireless audio. Packed with an unprecedented array of high-precision sensors, OpenEarable redefines what's possible in wearable tech. Designed for both development and research applications, OpenEarable is modular, reconfigurable, and built for the future.
 <br/><br/><br/>
-![image](https://github.com/user-attachments/assets/8cb55571-c6bc-4f51-b2ae-628f7be3661c)
+<img width="1323" height="568" alt="image" src="https://github.com/user-attachments/assets/ab4e2b0e-9645-4428-975f-466c7ef2f13b" />
+
 
 ## Table of Contents
 
@@ -63,56 +64,65 @@
         - Do not set any of the FOTA flags described above.
 
 9. **J-Link Setup**
-     - Wire your J-Link to the debugging breakout PCB as shown below.
-     ![image](https://github.com/user-attachments/assets/2eeec41e-6be1-4a4f-b986-7d9a07b0f8e5)
-     - If you do not own a J-Link yet, here are a few options (do **NOT** use J-Link clones, they will not work and are illegal!):
-          - [J-Link EDU Mini](https://mou.sr/3LrwiVe) (available to educational institutions, private persons, and students) with [JTAG adapter](https://www.adafruit.com/product/2094) and [cable](https://www.adafruit.com/product/1675).
-          - Full-scale J-Link for commercial use (e.g., [J-Link BASE Compact](https://mou.sr/4oQkAls)).
-          - ⚠️ The wiring show in the figure above is for the full-scale J-Link pinout. If you use the [JTAG adapter](https://www.adafruit.com/product/2094) the wiring may be different so make sure it is correct in your case! _(to be confirmed, picture coming soon)_.
-
-
-10. **Build and Flash**
+   - Wire your J-Link to the debugging breakout PCB as shown below.
+   ![image](https://github.com/user-attachments/assets/2eeec41e-6be1-4a4f-b986-7d9a07b0f8e5)
+   - If you do not own a J-Link yet, here are a few options (do **NOT** use J-Link clones, they will not work and are illegal!):
+      - [J-Link EDU Mini](https://mou.sr/3LrwiVe) (available to educational institutions, private persons, and students) with [JTAG adapter](https://www.adafruit.com/product/2094) and [cable](https://www.adafruit.com/product/1675).
+      - Full-scale J-Link for commercial use (e.g., [J-Link BASE Compact](https://mou.sr/4oQkAls)).
+      - ⚠️ The wiring show in the figure above is for the full-scale J-Link pinout. If you use the [JTAG adapter](https://www.adafruit.com/product/2094) the wiring may be different so make sure it is correct in your case!.
+
+11. **Build and Flash**
    - Click on `Generate and Build` and wait for the application to build (this will take some time)
    - Make sure your device is charged or powered via USB. If the battery is fully discharged, the charging management IC will no longer supply power to the MCU from the battery, so you won’t be able to flash the MCU unless the battery is charged or the device is directly powered via USB.
    - Open a new terminal in VS Code and run the following command from the root of the `open-earable-v2` directory to flash the FOTA build. Make sure to set the serial number of your J-Link (right click your J-Link in the `CONNECTED DEVICES` tab of the nRF connect extension and copy the serial number).
-     ```bash
-     # --right for the right ear device, or no flag to retain left/right bonding
-     # --hw version is optional and can only be used with --left or --right
-     ./tools/flash/flash_fota.sh --snr 123456789 --left --hw 2.0.1    
-
-     ```
+   ```bash
+   # --right for the right ear device, or no flag to retain left/right bonding, --standalone for no pair   
+   # --hw version is optional and can only be used with --left or --right
+   ./tools/flash/flash_fota.sh --snr 123456789 --left --hw 2.0.1    
+   ```
+
    - or without FOTA
-     ```bash
-     # --right for the right ear device, or no flag to retain left/right bonding
-      # --hw version is optional and can only be used with --left or --right
-     ./tools/flash/flash.sh --snr 123456789 --left --hw 2.0.1      
-     ```
+   ```bash
+   # --right for the right ear device, or no flag to retain left/right bonding, --standalone for no pair
+   # --hw version is optional and can only be used with --left or --right
+
+   ./tools/flash/flash.sh --snr 123456789 --left    
+   ```
+
    - The FOTA update script is also available for Windows as `./tools/flash/flash_fota.ps1`. To execute it, open PowerShell with administrative privileges.
 
 11. **Recover Board**
-- If the application or network core becomes unresponsive, or you encounter flashing issues, you can recover the board using the recovery script. The `--snr` parameter specifies the serial number of your J-Link debugger.
-- Ensure the device is powered via USB or that the battery is sufficiently charged before running the recovery process. Otherwise, the MCU may not power up correctly and the recovery will fail.
-     ```bash
-     ./tools/flash/recover.sh --snr 123456789
-     ```
-- After successful recovery, you can attempt to flash the firmware again (you will have to restore left/right bonding and hardware version).
+   - If the application or network core becomes unresponsive, or you encounter flashing issues, you can recover the board using the recovery script. The `--snr` parameter specifies the serial number of your J-Link debugger.
+   - Ensure the device is powered via USB or that the battery is sufficiently charged before running the recovery process. Otherwise, the MCU may not power up correctly and the recovery will fail.
+   ```bash
+   ./tools/flash/recover.sh --snr 123456789
+   ```
+   - After successful recovery, you can attempt to flash the firmware again.
 
 12. **Enable Debug Output**
-- Open the **J-Link Configuration** program on your computer.  
-   - On macOS: Press `CMD` + `Space` and search for `J-Link Config`.  
-   - On Windows: Search for the program from the taskbar.  
-- Ensure your J-Link is connected to your computer.  
-- In the **Connected via USB** table, locate your J-Link device. Double-click it or right-click and select **Configure**.  
-- Find the **Virtual COM-Port** option and select **Enable**. Click **OK** to apply the setting.  
-- Open **Visual Studio Code**.  
-- In the left sidebar, open the **Extensions** menu.  
-- Search for and install the [**Serial Monitor**](https://marketplace.visualstudio.com/items?itemName=ms-vscode.vscode-serial-monitor) extension.  
-- In the top menu bar, click **Terminal → New Terminal**.  
-- A terminal window will appear at the bottom of VS Code. Open the **Serial Monitor** tab.  
-- In the **Port** dropdown menu, select your J-Link’s COM port.  
-- Set the **Baud rate** to **115200**.  
-- Click **Start Monitoring**.  
-- Ensure your earable is connected to the debugger probe. You should now see debug output appearing when you interact with the device (e.g., press button).
+   - Open the **J-Link Configuration** program on your computer.  
+      - On macOS: Press `CMD` + `Space` and search for `J-Link Config`.  
+      - On Windows: Search for the program from the taskbar.  
+   - Ensure your J-Link is connected to your computer.  
+   - In the **Connected via USB** table, locate your J-Link device. Double-click it or right-click and select **Configure**.  
+   - Find the **Virtual COM-Port** option and select **Enable**. Click **OK** to apply the setting.  
+   - Open **Visual Studio Code**.  
+   - In the left sidebar, open the **Extensions** menu.  
+      - Search for and install the [**Serial Monitor**](https://marketplace.visualstudio.com/items?itemName=ms-vscode.vscode-serial-monitor) extension.  
+      - In the top menu bar, click **Terminal → New Terminal**.  
+      - A terminal window will appear at the bottom of VS Code. Open the **Serial Monitor** tab.  
+      - In the **Port** dropdown menu, select your J-Link’s COM port.  
+      - Set the **Baud rate** to **115200**.  
+      - Click **Start Monitoring**.  
+      - Ensure your earable is connected to the debugger probe. You should now see debug output appearing when you interact with the device (e.g., press button).
+
+13. **Recover Board**
+   - If the application or network core becomes unresponsive, or you encounter flashing issues, you can recover the board using the recovery script. The `--snr` parameter specifies the serial number of your J-Link debugger.
+   - Ensure the device is powered via USB or that the battery is sufficiently charged before running the recovery process. Otherwise, the MCU may not power up correctly and the recovery will fail.
+      ```bash
+      ./tools/flash/recover.sh --snr 123456789
+      ```
+   - After successful recovery, you can attempt to flash the firmware again (you will have to restore left/right bonding and hardware version).
 
 
 

diff --git a/VERSION b/VERSION
@@ -1,5 +1,5 @@
 VERSION_MAJOR = 2
 VERSION_MINOR = 2
-PATCHLEVEL = 1
+PATCHLEVEL = 2
 VERSION_TWEAK = 0
 EXTRAVERSION =
diff --git a/include/openearable_common.h b/include/openearable_common.h
@@ -12,8 +12,19 @@
 
 #define SENSOR_DATA_FIXED_LENGTH 38
 
+
 #define millis() k_cyc_to_ms_floor64(k_uptime_ticks())
-#define micros() k_cyc_to_us_floor64(k_uptime_ticks())
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+uint64_t oe_micros();
+#ifdef __cplusplus
+}
+#endif
+#ifndef micros
+#define micros() oe_micros()
+#endif
 
 #define load_switch_sd_id DT_NODELABEL(load_switch_sd)
 #define load_switch_1_8_id DT_NODELABEL(load_switch)

diff --git a/prj_fota.conf b/prj_fota.conf
@@ -260,4 +260,4 @@ CONFIG_MCUMGR_GRP_OS_RESET_HOOK=y
 
 #CONFIG_MCUMGR_GRP_SETTINGS_ACCESS_HOOK=y
 
-CONFIG_SETUP_FUEL_GAUGE=y
+CONFIG_SETUP_FUEL_GAUGE=y
diff --git a/src/ParseInfo/SensorScheme.cpp b/src/ParseInfo/SensorScheme.cpp
@@ -13,13 +13,6 @@
 
 LOG_MODULE_REGISTER(parse_info_service, CONFIG_LOG_DEFAULT_LEVEL);
 
-static void enable_notifies_handler(struct k_work *work)
-{
-    temp_disable_notifies(false);
-}
-
-K_WORK_DELAYABLE_DEFINE(enable_notifies_work, enable_notifies_handler);
-
 static char* parseInfoScheme;
 static size_t parseInfoSchemeSize;
 
@@ -40,11 +33,7 @@ static ssize_t read_parse_info(struct bt_conn *conn,
                 void *buf,
                 uint16_t len,
                 uint16_t offset) {
-	temp_disable_notifies(true);
     ssize_t ret = bt_gatt_attr_read(conn, attr, buf, len, offset, parseInfoScheme, parseInfoSchemeSize);
-
-    // re-enable notifications after a delay
-    k_work_schedule(&enable_notifies_work, K_MSEC(500));
 
     return ret;
 }

diff --git a/src/SensorManager/BMA580/BMA580_Sensor.cpp b/src/SensorManager/BMA580/BMA580_Sensor.cpp
@@ -191,14 +191,14 @@ int8_t BMA580::get_accel_and_int_settings(struct bma5_dev *dev)
     rslt = bma5_set_acc_conf(&acc_cfg, dev);
     bma5_check_rslt("bma5_get_acc_conf", rslt);
 
-    /*LOG_INF("Accel configurations");
-    LOG_INF("ODR : %s\t", enum_to_string(acc_cfg.acc_odr));
-    LOG_INF("Bandwidth : %s\t", enum_to_string(BMA5_ACC_BWP_NORM_AVG4));
-    LOG_INF("Power mode : %s\t", enum_to_string(BMA5_POWER_MODE_HPM));
-    LOG_INF("Range : %s\t", enum_to_string(BMA5_ACC_RANGE_MAX_2G));
-    LOG_INF("IIR RO : %s\t", enum_to_string(BMA5_ACC_IIR_RO_DB_60));
-    LOG_INF("Noise mode : %s\t", enum_to_string(BMA5_NOISE_MODE_LOWER_POWER));
-    LOG_INF("Auto Int clear : %s\t", enum_to_string(BMA5_ACC_DRDY_INT_AUTO_CLEAR_DISABLED));*/
+    /*LOG_DBG("Accel configurations");
+    LOG_DBG("ODR : %s\t", enum_to_string(acc_cfg.acc_odr));
+    LOG_DBG("Bandwidth : %s\t", enum_to_string(BMA5_ACC_BWP_NORM_AVG4));
+    LOG_DBG("Power mode : %s\t", enum_to_string(BMA5_POWER_MODE_HPM));
+    LOG_DBG("Range : %s\t", enum_to_string(BMA5_ACC_RANGE_MAX_2G));
+    LOG_DBG("IIR RO : %s\t", enum_to_string(BMA5_ACC_IIR_RO_DB_60));
+    LOG_DBG("Noise mode : %s\t", enum_to_string(BMA5_NOISE_MODE_LOWER_POWER));
+    LOG_DBG("Auto Int clear : %s\t", enum_to_string(BMA5_ACC_DRDY_INT_AUTO_CLEAR_DISABLED));*/
 
     /* Enable accel */
     sensor_ctrl = BMA5_SENSOR_CTRL_ENABLE;
@@ -208,7 +208,7 @@ int8_t BMA580::get_accel_and_int_settings(struct bma5_dev *dev)
 
     if (rslt == BMA5_OK)
     {
-        LOG_INF("Accel enabled");
+        LOG_DBG("Accel enabled");
     }
 
     rslt = bma5_get_acc_conf_0(&sensor_ctrl, dev);
@@ -227,10 +227,10 @@ int8_t BMA580::get_accel_and_int_settings(struct bma5_dev *dev)
     rslt = bma5_set_int_conf(&int_config, n_ints, dev);
     bma5_check_rslt("bma5_set_int_conf", rslt);
 
-    /*LOG_INF("\nInt Configurations");
-    LOG_INF("INT2 mode : %s\t", enum_to_string(BMA5_INT2_MODE_LATCHED));
-    LOG_INF("INT2 OD : %s\t", enum_to_string(BMA5_INT2_OD_PUSH_PULL));
-    LOG_INF("INT2 level : %s\t", enum_to_string(BMA5_INT2_LVL_ACTIVE_HIGH));*/
+    /*LOG_DBG("\nInt Configurations");
+    LOG_DBG("INT2 mode : %s\t", enum_to_string(BMA5_INT2_MODE_LATCHED));
+    LOG_DBG("INT2 OD : %s\t", enum_to_string(BMA5_INT2_OD_PUSH_PULL));
+    LOG_DBG("INT2 level : %s\t", enum_to_string(BMA5_INT2_LVL_ACTIVE_HIGH));*/
 
     return rslt;
 }
@@ -261,9 +261,7 @@ int BMA580::init(int odr, int fifo_watermark_level) {
     //struct bma5_fifo_conf fifo_conf;
 
     /* Assign context parameter selection */
-    enum bma5_context context;
-
-    context = BMA5_HEARABLE;
+    enum bma5_context context = BMA5_HEARABLE;
 
     _odr = odr;
 
@@ -276,7 +274,7 @@ int BMA580::init(int odr, int fifo_watermark_level) {
 
 	rslt = bma580_init(&dev);
     bma5_check_rslt("bma580_init", rslt);
-    LOG_INF("Chip ID :0x%X", dev.chip_id);
+    LOG_DBG("Chip ID :0x%X", dev.chip_id);
 
     /* Map generic interrupts to hardware interrupt pin of the sensor */
     rslt = bma580_get_int_map(&int_map, &dev);

diff --git a/src/SensorManager/Baro.cpp b/src/SensorManager/Baro.cpp
@@ -15,6 +15,8 @@ Adafruit_BMP3XX Baro::bmp;
 
 Baro Baro::sensor;
 
+static int baro_initial_discard = 1;
+
 // Initialisierung der SampleRateSettings für Baro (BMP3)
 const SampleRateSetting<18> Baro::sample_rates = {
     { BMP3_ODR_0_001_HZ, BMP3_ODR_0_003_HZ, BMP3_ODR_0_006_HZ, BMP3_ODR_0_01_HZ, 
@@ -37,6 +39,11 @@ void Baro::update_sensor(struct k_work *work) {
 
 	bmp.performReading();
 
+	if (baro_initial_discard > 0) {
+		baro_initial_discard--;
+		return;
+	}
+
 	msg_baro.sd = sensor._sd_logging;
 	msg_baro.stream = sensor._ble_stream;
 
@@ -84,6 +91,8 @@ bool Baro::init(struct k_msgq * queue) {
 }
 
 void Baro::start(int sample_rate_idx) {
+	baro_initial_discard = 1;
+
     k_timeout_t t = K_USEC(1e6 / sample_rates.true_sample_rates[sample_rate_idx]);
 
     //bmp.set_interrogation_rate(setting.reg_val);

diff --git a/src/SensorManager/BoneConduction.cpp b/src/SensorManager/BoneConduction.cpp
@@ -76,7 +76,9 @@ void BoneConduction::update_sensor(struct k_work *work) {
 
         msg_bc.data.id = ID_BONE_CONDUCTION;
         msg_bc.data.size = to_write * _size + sizeof(uint16_t);
-        msg_bc.data.time = _time_stamp - (num_samples - written) * BoneConduction::sensor.t_sample_us;
+
+        uint64_t dt_us = (uint64_t)((double)(num_samples - written) * (double)BoneConduction::sensor.t_sample_us);
+        msg_bc.data.time = _time_stamp - dt_us;
 
         if (to_write > 1) {
             uint16_t t_diff = BoneConduction::sensor.t_sample_us;

diff --git a/src/SensorManager/PPG.cpp b/src/SensorManager/PPG.cpp
@@ -102,7 +102,9 @@ void PPG::update_sensor(struct k_work *work) {
 
             msg_ppg.data.id = ID_PPG;
             msg_ppg.data.size = to_write * _size + sizeof(uint16_t);
-            msg_ppg.data.time = _time_stamp - (num_samples - written) * PPG::sensor.t_sample_us;
+
+            const uint64_t dt_us = (uint64_t)((double)(num_samples - written) * (double)PPG::sensor.t_sample_us);
+            msg_ppg.data.time = _time_stamp - dt_us;
 
             if (to_write > 1) {
                 uint16_t t_diff = PPG::sensor.t_sample_us;

diff --git a/src/audio/anc_fxlms_wrapper.cpp b/src/audio/anc_fxlms_wrapper.cpp
diff --git a/src/audio/anc_fxlms_wrapper.h b/src/audio/anc_fxlms_wrapper.h
diff --git a/src/audio/audio_datapath.c b/src/audio/audio_datapath.c
@@ -755,6 +755,11 @@ static void alt_buffer_free_both(void)
 	alt.buf_1_in_use = false;
 }
 
+__attribute__((weak)) void bt_mgmt_report_audio_underrun(uint32_t count) {
+	LOG_ERR("Audio underrun reported to bt_mgmt");
+}
+
+
 /*
  * This handler function is called every time I2S needs new buffers for
  * TX and RX data.
@@ -792,6 +797,7 @@ static void audio_datapath_i2s_blk_complete(uint32_t frame_start_ts_us, uint32_t
 					underrun_condition = false;
 					LOG_WRN("Data received, total under-runs: %d",
 						ctrl_blk.out.total_blk_underruns);
+					bt_mgmt_report_audio_underrun(ctrl_blk.out.total_blk_underruns);
 				}
 
 				tx_buf = (uint8_t *)&ctrl_blk.out

diff --git a/src/bluetooth/bt_management/CMakeLists.txt b/src/bluetooth/bt_management/CMakeLists.txt
@@ -14,7 +14,10 @@ zephyr_library_include_directories(
 
 target_sources(app PRIVATE
 	       ${CMAKE_CURRENT_SOURCE_DIR}/bt_mgmt.c
+	       ${CMAKE_CURRENT_SOURCE_DIR}/bt_mgmt_conn_interval.cpp
 	       ${CMAKE_CURRENT_SOURCE_DIR}/controller_config/bt_mgmt_ctlr_cfg.c
+		   ${CMAKE_CURRENT_SOURCE_DIR}/conn_interval/conn_intvl_exp_backoff_lin_inc.cpp
+		   ${CMAKE_CURRENT_SOURCE_DIR}/conn_interval/conn_intvl_linear.cpp
 )
 
 if (CONFIG_BT_CENTRAL)

diff --git a/src/bluetooth/bt_management/bt_mgmt.c b/src/bluetooth/bt_management/bt_mgmt.c
@@ -23,6 +23,7 @@
 #include "bt_mgmt_ctlr_cfg_internal.h"
 #include "bt_mgmt_adv_internal.h"
 #include "bt_mgmt_dfu_internal.h"
+#include "bt_mgmt_conn_interval.h"
 
 #include "BootState.h"
 
@@ -87,6 +88,8 @@ static void conn_params_updated(struct bt_conn *conn, uint16_t interval, uint16_
 
 	LOG_INF("Conn params updated: interval %d unit, latency %d, timeout: %d0 ms",interval, latency, timeout);
 
+	bt_mgmt_ci_on_conn_param_updated(conn, interval, latency, timeout);
+
 	/*msg.event = BT_MGMT_CONNECTED;
 	msg.conn = conn;
 
@@ -162,14 +165,18 @@ static void connected_cb(struct bt_conn *conn, uint8_t err)
 		LOG_ERR("Cannot update conneciton parameter (err: %d)", err);
 		return err;
 	}
-	LOG_INF("Connection parameters update requested");
+	LOG_INF("Connection parameters update requested: interval_min %d interval_max %d latency %d timeout %d",
+		conn_param->interval_min, conn_param->interval_max,
+		conn_param->latency, conn_param->timeout);
+	bt_mgmt_ci_on_connected(conn);
 
 	if (IS_ENABLED(CONFIG_BT_CENTRAL)) {
 		ret = bt_conn_set_security(conn, BT_SECURITY_L2);
 		if (ret) {
 			LOG_ERR("Failed to set security to L2: %d", ret);
 		}
 	}
+
 }
 
 K_MUTEX_DEFINE(mtx_duplicate_scan);
Original file line number	Diff line number	Diff line change
Expand Up		@@ -260,4 +260,4 @@ CONFIG_MCUMGR_GRP_OS_RESET_HOOK=y

		#CONFIG_MCUMGR_GRP_SETTINGS_ACCESS_HOOK=y

		CONFIG_SETUP_FUEL_GAUGE=y
		CONFIG_SETUP_FUEL_GAUGE=y