style: added docs

main/ate0005.c

@@ -1,46 +1,261 @@
 #include "ate0005.h"
 
-static task_stats_t _task_stats = {A_INCLINOMETER_TASK_STACK_SIZE, B_INCLINOMETER_TASK_STACK_SIZE, A_TACHOMETER_TASK_STACK_SIZE, B_TACHOMETER_TASK_STACK_SIZE};
+/**
+ * @brief Internal structure holding the tasks minimum free stack sizes.
+ *
+ * Each field stores the high water mark of the corresponding processing
+ * task, reported by uxTaskGetStackHighWaterMark(). The statistics task reads
+ * these values to log stack usage and to raise a warning when a value falls
+ * below the threshold.
+ */
+typedef struct
+{
+    uint32_t a_inclinometer_task_min_stack_size; /*!< Minimum free stack size of the A inclinometer task */
+    uint32_t b_inclinometer_task_min_stack_size; /*!< Minimum free stack size of the B inclinometer task */
+    uint32_t a_tachometer_task_min_stack_size;   /*!< Minimum free stack size of the A tachometer task */
+    uint32_t b_tachometer_task_min_stack_size;   /*!< Minimum free stack size of the B tachometer task */
+} _task_stats_t;
 
-static httpd_handle_t _http_server_handle = NULL;
-
-static zh_pcf8574_handle_t _lcd_handle = {0};
-static zh_encoder_handle_t _mode_encoder_handle = {0};
-static zh_inclinometer_handle_t _a_inclinometer_handle = {0};
-static zh_inclinometer_handle_t _b_inclinometer_handle = {0};
-static zh_tachometer_handle_t _a_tachometer_handle = {0};
-static zh_tachometer_handle_t _b_tachometer_handle = {0};
-static esp_timer_handle_t _inclinometer_reset_timer_handle = {0};
-
-static SemaphoreHandle_t _lcd_mutex = NULL;
-static TaskHandle_t _a_inclinometer_task_handle = NULL;
-static TaskHandle_t _b_inclinometer_task_handle = NULL;
-static TaskHandle_t _a_tachometer_task_handle = NULL;
-static TaskHandle_t _b_tachometer_task_handle = NULL;
-static TaskHandle_t _zh_stats_task_handle = NULL;
+static httpd_handle_t _http_server_handle = NULL;                 /*!< HTTP server handle */
+static zh_pcf8574_handle_t *_lcd_handle = NULL;                   /*!< PCF8574 LCD expander handle */
+static zh_160x_i2c_handle_t *_lcd_160x_handle = NULL;             /*!< 16x2 LCD display handle */
+static zh_encoder_handle_t *_mode_encoder_handle = NULL;          /*!< Mode selector rotary encoder handle */
+static zh_inclinometer_handle_t *_a_inclinometer_handle = NULL;   /*!< A channel inclinometer handle */
+static zh_inclinometer_handle_t *_b_inclinometer_handle = NULL;   /*!< B channel inclinometer handle */
+static zh_tachometer_handle_t *_a_tachometer_handle = NULL;       /*!< A channel tachometer handle */
+static zh_tachometer_handle_t *_b_tachometer_handle = NULL;       /*!< B channel tachometer handle */
+static esp_timer_handle_t _inclinometer_reset_timer_handle = {0}; /*!< Inclinometer reset software timer handle */
+static SemaphoreHandle_t _lcd_mutex = NULL;                       /*!< Mutex to protect the LCD display access */
+static TaskHandle_t _a_inclinometer_task_handle = NULL;           /*!< Handle of the A inclinometer processing task */
+static TaskHandle_t _b_inclinometer_task_handle = NULL;           /*!< Handle of the B inclinometer processing task */
+static TaskHandle_t _a_tachometer_task_handle = NULL;             /*!< Handle of the A tachometer processing task */
+static TaskHandle_t _b_tachometer_task_handle = NULL;             /*!< Handle of the B tachometer processing task */
+static TaskHandle_t _zh_stats_task_handle = NULL;                 /*!< Handle of the statistics processing task */
 
+/**
+ * @brief Initialize WiFi in AP+STA mode.
+ *
+ * Creates default AP and STA netifs, configures the AP with the SSID,
+ * password, channel and maximum number of connections and the STA with the
+ * SSID and password. Registers the Wi-Fi event handler and starts Wi-Fi.
+ */
 static void _zh_wifi_init(void);
+
+/**
+ * @brief Initialize the web server with OTA support.
+ *
+ * Starts the HTTP server with default configuration and registers the OTA
+ * update page handler at the root URI.
+ */
 static void _zh_webserver_init(void);
+
+/**
+ * @brief Initialize the ESP-NOW wireless protocol.
+ *
+ * Not implemented yet.
+ */
 static void _zh_espnow_init(void);
+
+/**
+ * @brief Initialize the mode selector rotary encoder.
+ *
+ * Registers the encoder event handler and initializes the encoder with the
+ * task configuration, GPIO numbers, queue size and position limits
+ * corresponding to the number of main menu entries.
+ */
 static void _zh_encoder_init(void);
+
+/**
+ * @brief Initialize the A channel inclinometer.
+ *
+ * Initializes the inclinometer with the A channel optical device GPIO numbers
+ * and the encoder pulse count, then creates the A inclinometer processing
+ * task.
+ */
 static void _zh_a_inclinometer_init(void);
+
+/**
+ * @brief Initialize the B channel inclinometer.
+ *
+ * Initializes the inclinometer with the B channel optical device GPIO numbers
+ * and the encoder pulse count, then creates the B inclinometer processing
+ * task.
+ */
 static void _zh_b_inclinometer_init(void);
+
+/**
+ * @brief Initialize the A channel tachometer.
+ *
+ * Initializes the tachometer with the A channel optical device GPIO numbers
+ * and the encoder pulse count, then creates the A tachometer processing
+ * task.
+ */
 static void _zh_a_tachometer_init(void);
+
+/**
+ * @brief Initialize the B channel tachometer.
+ *
+ * Initializes the tachometer with the B channel optical device GPIO numbers
+ * and the encoder pulse count, then creates the B tachometer processing
+ * task.
+ */
 static void _zh_b_tachometer_init(void);
+
+/**
+ * @brief Initialize the PCF8574 I2C expander of the LCD display.
+ *
+ * Creates the I2C master bus, initializes the PCF8574 expander with the task
+ * configuration and I2C address, initializes the 16x2 LCD driver on top of
+ * it and creates the LCD access mutex.
+ */
 static void _zh_pcf8574_init(void);
+
+/**
+ * @brief Show the system loading screen on the LCD display.
+ *
+ * Displays the manufacturer name, project name and firmware version, then an
+ * animated progress bar. After loading, shows the current operating mode
+ * label.
+ */
 static void _zh_system_load(void);
+
+/**
+ * @brief Create the inclinometer reset timer.
+ *
+ * Creates a one-shot software timer that resets the inclinometer angle on
+ * long press of the mode encoder button.
+ */
 static void _zh_timer_init(void);
+
+/**
+ * @brief Handle the mode encoder events.
+ *
+ * On button press starts the inclinometer reset timer and enters reset mode.
+ * On button release stops the timer and either ignores the event if the reset
+ * already occurred, or toggles the menu mode.
+ *
+ * Entering the menu mode stops the tasks and deinitializes the active devices
+ * of the current operating mode and enables the LCD cursor. Leaving the menu
+ * mode initializes the devices of the selected mode.
+ *
+ * On encoder rotation in the menu mode updates and displays the selected menu
+ * entry, otherwise restores the encoder position to the current menu value.
+ *
+ * @param arg User data registered with the event handler (unused)
+ * @param event_base Event base of the registered event
+ * @param event_id ID of the encoder or button event
+ * @param event_data Pointer to the event payload structure
+ */
 static void _zh_encoder_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
+
+/**
+ * @brief Handle the ESP-NOW events.
+ *
+ * Not implemented yet.
+ *
+ * @param arg User data registered with the event handler (unused)
+ * @param event_base Event base of the registered event
+ * @param event_id ID of the ESP-NOW event (unused)
+ * @param event_data Pointer to the event payload (unused)
+ */
 static void _zh_espnow_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
+
+/**
+ * @brief Handle the Wi-Fi station events.
+ *
+ * Initiates connection on station start, reconnects with a limited number of
+ * retries on disconnection and stops the syslog statistics task. On IP
+ * assignment resets the retry counter, initializes the syslog client and
+ * creates the statistics processing task.
+ *
+ * @param arg User data registered with the event handler (unused)
+ * @param event_base Event base of the registered event
+ * @param event_id ID of the Wi-Fi or IP event
+ * @param event_data Pointer to the event payload structure (unused)
+ */
 static void _zh_wifi_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
+
+/**
+ * @brief Inclinometer reset timer callback.
+ *
+ * Called on long press of the mode encoder button. Resets the angle of the
+ * active inclinometers of the current operating mode when the device is not
+ * in the menu mode.
+ *
+ * @param arg User data registered with the timer (unused)
+ */
 static void _zh_inclinometer_reset_timer_on_alarm_cb(void *arg);
 
+/**
+ * @brief A channel inclinometer processing task.
+ *
+ * Displays the A channel angle with 1 decimal place on the second LCD row.
+ * The value is refreshed only when it changes. Updates the task minimum free
+ * stack size for the statistics task.
+ *
+ * @param pvParameter Task parameter (unused)
+ */
 static void _zh_a_inclinometer_processing_task(void *pvParameter);
+
+/**
+ * @brief B channel inclinometer processing task.
+ *
+ * Displays the B channel angle with 1 decimal place on the second LCD row.
+ * The value is refreshed only when it changes. Updates the task minimum free
+ * stack size for the statistics task.
+ *
+ * @param pvParameter Task parameter (unused)
+ */
 static void _zh_b_inclinometer_processing_task(void *pvParameter);
+
+/**
+ * @brief A channel tachometer processing task.
+ *
+ * Displays the A channel RPM on the second LCD row. The value is refreshed
+ * only when it changes. Updates the task minimum free stack size for the
+ * statistics task.
+ *
+ * @param pvParameter Task parameter (unused)
+ */
 static void _zh_a_tachometer_processing_task(void *pvParameter);
+
+/**
+ * @brief B channel tachometer processing task.
+ *
+ * Displays the B channel RPM on the second LCD row. The value is refreshed
+ * only when it changes. Updates the task minimum free stack size for the
+ * statistics task.
+ *
+ * @param pvParameter Task parameter (unused)
+ */
 static void _zh_b_tachometer_processing_task(void *pvParameter);
+
+/**
+ * @brief Statistics processing task.
+ *
+ * Periodically sends the tasks minimum free stack sizes and the component
+ * error counters to the remote syslog server. Messages are logged with the
+ * warning severity when a stack size falls below the threshold or an error
+ * counter is not zero.
+ *
+ * @param pvParameter Task parameter (unused)
+ */
 static void _zh_stats_processing_task(void *pvParameter);
 
+/**
+ * @brief Main application entry point.
+ *
+ * Initializes NVS flash with erase and re-init on empty or version mismatch,
+ * the default event loop, the PCF8574 LCD expander, the system loading
+ * screen, the mode encoder, the inclinometer reset timer, the A and B
+ * inclinometers, WiFi in AP+STA mode, the web server and ESP-NOW.
+ *
+ * Then performs the OTA rollback self-check: if the running image is pending
+ * verification, waits 60 seconds and marks it as valid.
+ */
+void app_main(void);
+
+volatile static _task_stats_t _task_stats = {A_INCLINOMETER_TASK_STACK_SIZE, B_INCLINOMETER_TASK_STACK_SIZE, A_TACHOMETER_TASK_STACK_SIZE, B_TACHOMETER_TASK_STACK_SIZE};
 static const char *_main_menu[] = {MAIN_MENU_ANGLE_ANGLE_NAME, MAIN_MENU_TACHO_TACHO_NAME, MAIN_MENU_ANGLE_TACHO_NAME, MAIN_MENU_REMOTE_NAME};
 volatile static bool _is_menu_mode = false;
 volatile static bool _is_reset_mode = false;
@@ -51,8 +266,12 @@ volatile static bool _is_wifi_connected = false;
 
 void app_main(void)
 {
-    _lcd_mutex = xSemaphoreCreateMutex();
-    nvs_flash_init();
+    esp_err_t err = nvs_flash_init();
+    if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND)
+    {
+        ESP_ERROR_CHECK(nvs_flash_erase());
+        ESP_ERROR_CHECK(nvs_flash_init());
+    }
     esp_event_loop_create_default();
     _zh_pcf8574_init();
     _zh_system_load();
@@ -108,7 +327,6 @@ static void _zh_webserver_init(void)
 
 static void _zh_espnow_init(void)
 {
-    // To Do.
 }
 
 static void _zh_encoder_init(void)
@@ -121,7 +339,6 @@ static void _zh_encoder_init(void)
     config.a_gpio_number = MODE_ENCODER_A_GPIO;
     config.b_gpio_number = MODE_ENCODER_B_GPIO;
     config.s_gpio_number = MODE_ENCODER_S_GPIO;
-    config.s_gpio_debounce_time = 1000;
     config.encoder_min_value = 0;
     config.encoder_max_value = (sizeof(_main_menu) / sizeof(_main_menu[0])) - 1;
     config.encoder_step = 1;
@@ -137,8 +354,8 @@ static void _zh_a_inclinometer_init(void)
     config.b_gpio_number = A_OPTICAL_DEVICE_B_GPIO;
     config.encoder_pulses = 3600;
     zh_inclinometer_init(&config, &_a_inclinometer_handle);
-    xTaskCreatePinnedToCore(&_zh_a_inclinometer_processing_task, "a_inclinometer_processing_task", A_INCLINOMETER_TASK_STACK_SIZE, NULL, A_INCLINOMETER_TASK_PRIORITY,
-                            &_a_inclinometer_task_handle, tskNO_AFFINITY);
+    xTaskCreatePinnedToCore(&_zh_a_inclinometer_processing_task, "a_inclinometer_processing_task", A_INCLINOMETER_TASK_STACK_SIZE, NULL,
+                            A_INCLINOMETER_TASK_PRIORITY, &_a_inclinometer_task_handle, tskNO_AFFINITY);
 }
 
 static void _zh_b_inclinometer_init(void)
@@ -148,8 +365,8 @@ static void _zh_b_inclinometer_init(void)
     config.b_gpio_number = B_OPTICAL_DEVICE_B_GPIO;
     config.encoder_pulses = 3600;
     zh_inclinometer_init(&config, &_b_inclinometer_handle);
-    xTaskCreatePinnedToCore(&_zh_b_inclinometer_processing_task, "b_inclinometer_processing_task", B_INCLINOMETER_TASK_STACK_SIZE, NULL, B_INCLINOMETER_TASK_PRIORITY,
-                            &_b_inclinometer_task_handle, tskNO_AFFINITY);
+    xTaskCreatePinnedToCore(&_zh_b_inclinometer_processing_task, "b_inclinometer_processing_task", B_INCLINOMETER_TASK_STACK_SIZE, NULL,
+                            B_INCLINOMETER_TASK_PRIORITY, &_b_inclinometer_task_handle, tskNO_AFFINITY);
 }
 
 static void _zh_a_tachometer_init(void)
@@ -159,8 +376,8 @@ static void _zh_a_tachometer_init(void)
     config.b_gpio_number = A_OPTICAL_DEVICE_B_GPIO;
     config.encoder_pulses = 3600;
     zh_tachometer_init(&config, &_a_tachometer_handle);
-    xTaskCreatePinnedToCore(&_zh_a_tachometer_processing_task, "a_tachometer_processing_task", A_TACHOMETER_TASK_STACK_SIZE, NULL, A_TACHOMETER_TASK_PRIORITY,
-                            &_a_tachometer_task_handle, tskNO_AFFINITY);
+    xTaskCreatePinnedToCore(&_zh_a_tachometer_processing_task, "a_tachometer_processing_task", A_TACHOMETER_TASK_STACK_SIZE, NULL,
+                            A_TACHOMETER_TASK_PRIORITY, &_a_tachometer_task_handle, tskNO_AFFINITY);
 }
 
 static void _zh_b_tachometer_init(void)
@@ -170,8 +387,8 @@ static void _zh_b_tachometer_init(void)
     config.b_gpio_number = B_OPTICAL_DEVICE_B_GPIO;
     config.encoder_pulses = 3600;
     zh_tachometer_init(&config, &_b_tachometer_handle);
-    xTaskCreatePinnedToCore(&_zh_b_tachometer_processing_task, "b_tachometer_processing_task", B_TACHOMETER_TASK_STACK_SIZE, NULL, B_TACHOMETER_TASK_PRIORITY,
-                            &_b_tachometer_task_handle, tskNO_AFFINITY);
+    xTaskCreatePinnedToCore(&_zh_b_tachometer_processing_task, "b_tachometer_processing_task", B_TACHOMETER_TASK_STACK_SIZE, NULL,
+                            B_TACHOMETER_TASK_PRIORITY, &_b_tachometer_task_handle, tskNO_AFFINITY);
 }
 
 static void _zh_pcf8574_init(void)
@@ -191,34 +408,35 @@ static void _zh_pcf8574_init(void)
     config.i2c_handle = _i2c_bus_handle;
     config.i2c_address = LCD_I2C_ADDRESS;
     zh_pcf8574_init(&config, &_lcd_handle);
-    zh_160x_init(&_lcd_handle, ZH_LCD_16X2);
+    zh_160x_init(&_lcd_handle, &_lcd_160x_handle, ZH_LCD_16X2);
+    _lcd_mutex = xSemaphoreCreateMutex();
 }
 
 static void _zh_system_load(void)
 {
-    zh_160x_set_cursor(&_lcd_handle, 0, 0);
-    zh_160x_print_char(&_lcd_handle, "LLC AEROTECH");
-    zh_160x_set_cursor(&_lcd_handle, 1, 0);
+    zh_160x_set_cursor(&_lcd_160x_handle, 0, 0);
+    zh_160x_print_char(&_lcd_160x_handle, "LLC AEROTECH");
+    zh_160x_set_cursor(&_lcd_160x_handle, 1, 0);
     const esp_app_desc_t *esp_app_desc = esp_app_get_description();
-    zh_160x_print_char(&_lcd_handle, esp_app_desc->project_name);
-    zh_160x_set_cursor(&_lcd_handle, 1, 8);
-    zh_160x_print_char(&_lcd_handle, "V");
-    zh_160x_print_char(&_lcd_handle, esp_app_desc->version);
+    zh_160x_print_char(&_lcd_160x_handle, esp_app_desc->project_name);
+    zh_160x_set_cursor(&_lcd_160x_handle, 1, 8);
+    zh_160x_print_char(&_lcd_160x_handle, "V");
+    zh_160x_print_char(&_lcd_160x_handle, esp_app_desc->version);
     vTaskDelay(1000 / portTICK_PERIOD_MS);
-    zh_160x_lcd_clear(&_lcd_handle);
-    zh_160x_set_cursor(&_lcd_handle, 0, 0);
-    zh_160x_print_char(&_lcd_handle, "SYSTEM LOADING:");
+    zh_160x_lcd_clear(&_lcd_160x_handle);
+    zh_160x_set_cursor(&_lcd_160x_handle, 0, 0);
+    zh_160x_print_char(&_lcd_160x_handle, "SYSTEM LOADING:");
     for (uint8_t i = 0; i <= 100; i += 10)
     {
-        zh_160x_print_progress_bar(&_lcd_handle, 1, i);
+        zh_160x_print_progress_bar(&_lcd_160x_handle, 1, i);
         vTaskDelay(100 / portTICK_PERIOD_MS);
     }
     vTaskDelay(500 / portTICK_PERIOD_MS);
-    zh_160x_lcd_clear(&_lcd_handle);
+    zh_160x_lcd_clear(&_lcd_160x_handle);
     vTaskDelay(500 / portTICK_PERIOD_MS);
-    zh_160x_set_cursor(&_lcd_handle, 0, 0);
-    zh_160x_print_char(&_lcd_handle, "MODE:");
-    zh_160x_print_char(&_lcd_handle, _main_menu[0]);
+    zh_160x_set_cursor(&_lcd_160x_handle, 0, 0);
+    zh_160x_print_char(&_lcd_160x_handle, "MODE:");
+    zh_160x_print_char(&_lcd_160x_handle, _main_menu[0]);
 }
 
 static void _zh_timer_init(void)
@@ -231,11 +449,12 @@ static void _zh_timer_init(void)
 
 static void _zh_encoder_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
 {
+    (void)arg;
     switch (event_id)
     {
     case ZH_BUTTON_EVENT:
-        zh_encoder_button_event_on_isr_t *button_event = event_data;
-        if (button_event->button_status == ENCODER_BUTTON_PRESSED)
+        zh_encoder_button_event_on_isr_t *button_event = (zh_encoder_button_event_on_isr_t *)event_data;
+        if (button_event->button_status == ZH_ENCODER_BUTTON_STATUS_PRESSED)
         {
             esp_timer_start_once(_inclinometer_reset_timer_handle, 2000000);
             _is_reset_mode = true;
@@ -258,36 +477,53 @@ static void _zh_encoder_event_handler(void *arg, esp_event_base_t event_base, in
                 switch (_current_menu_value)
                 {
                 case MODE_ANGLE_ANGLE:
-                    vTaskDelete(_a_inclinometer_task_handle);
-                    vTaskDelete(_b_inclinometer_task_handle);
+                    if (_a_inclinometer_task_handle != NULL)
+                    {
+                        vTaskDelete(_a_inclinometer_task_handle);
+                    }
+                    if (_b_inclinometer_task_handle != NULL)
+                    {
+                        vTaskDelete(_b_inclinometer_task_handle);
+                    }
                     zh_inclinometer_deinit(&_a_inclinometer_handle);
                     zh_inclinometer_deinit(&_b_inclinometer_handle);
                     break;
                 case MODE_TACHO_TACHO:
-                    vTaskDelete(_a_tachometer_task_handle);
-                    vTaskDelete(_b_tachometer_task_handle);
+                    if (_a_tachometer_task_handle != NULL)
+                    {
+                        vTaskDelete(_a_tachometer_task_handle);
+                    }
+                    if (_b_tachometer_task_handle != NULL)
+                    {
+                        vTaskDelete(_b_tachometer_task_handle);
+                    }
                     zh_tachometer_deinit(&_a_tachometer_handle);
                     zh_tachometer_deinit(&_b_tachometer_handle);
                     break;
                 case MODE_ANGLE_TACHO:
-                    vTaskDelete(_a_inclinometer_task_handle);
-                    vTaskDelete(_b_tachometer_task_handle);
+                    if (_a_inclinometer_task_handle != NULL)
+                    {
+                        vTaskDelete(_a_inclinometer_task_handle);
+                    }
+                    if (_b_tachometer_task_handle != NULL)
+                    {
+                        vTaskDelete(_b_tachometer_task_handle);
+                    }
                     zh_inclinometer_deinit(&_a_inclinometer_handle);
                     zh_tachometer_deinit(&_b_tachometer_handle);
                     break;
                 case MODE_REMOTE:
-                    // To Do.
                     break;
                 default:
                     break;
                 }
-                zh_160x_clear_row(&_lcd_handle, 1);
-                zh_160x_set_cursor(&_lcd_handle, 0, 0);
-                zh_160x_on_cursor(&_lcd_handle, true);
+                zh_160x_clear_row(&_lcd_160x_handle, 1);
+                zh_160x_set_cursor(&_lcd_160x_handle, 0, 0);
+                zh_160x_on_cursor(&_lcd_160x_handle, true);
             }
             else
             {
-                zh_160x_off_cursor(&_lcd_handle);
+                zh_160x_off_cursor(&_lcd_160x_handle);
                 switch (_current_menu_value)
                 {
                 case MODE_ANGLE_ANGLE:
@@ -303,8 +539,8 @@ static void _zh_encoder_event_handler(void *arg, esp_event_base_t event_base, in
                     _zh_b_tachometer_init();
                     break;
                 case MODE_REMOTE:
-                    zh_160x_set_cursor(&_lcd_handle, 1, 0);
-                    zh_160x_print_char(&_lcd_handle, "NOT CONNECTED");
+                    zh_160x_set_cursor(&_lcd_160x_handle, 1, 0);
+                    zh_160x_print_char(&_lcd_160x_handle, "NOT CONNECTED");
                     break;
                 default:
                     break;
@@ -313,15 +549,15 @@ static void _zh_encoder_event_handler(void *arg, esp_event_base_t event_base, in
         }
         break;
     case ZH_ENCODER_EVENT:
-        zh_encoder_event_on_isr_t *encoder_event = event_data;
+        zh_encoder_event_on_isr_t *encoder_event = (zh_encoder_event_on_isr_t *)event_data;
         if (_is_menu_mode == true)
         {
-            _current_menu_value = (uint8_t)encoder_event->encoder_position; // -V2004
-            zh_160x_clear_row(&_lcd_handle, 0);
-            zh_160x_set_cursor(&_lcd_handle, 0, 0);
-            zh_160x_print_char(&_lcd_handle, "MODE:");
-            zh_160x_print_char(&_lcd_handle, _main_menu[(uint8_t)encoder_event->encoder_position]); // -V2004
-            zh_160x_set_cursor(&_lcd_handle, 0, 0);
+            _current_menu_value = (uint8_t)encoder_event->encoder_position;
+            zh_160x_clear_row(&_lcd_160x_handle, 0);
+            zh_160x_set_cursor(&_lcd_160x_handle, 0, 0);
+            zh_160x_print_char(&_lcd_160x_handle, "MODE:");
+            zh_160x_print_char(&_lcd_160x_handle, _main_menu[(uint8_t)encoder_event->encoder_position]);
+            zh_160x_set_cursor(&_lcd_160x_handle, 0, 0);
         }
         else
         {
@@ -335,11 +571,12 @@ static void _zh_encoder_event_handler(void *arg, esp_event_base_t event_base, in
 
 static void _zh_espnow_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
 {
-    // To Do.
 }
 
 static void _zh_wifi_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
 {
+    (void)arg;
+    (void)event_data;
     switch (event_id)
     {
     case WIFI_EVENT_STA_START:
@@ -348,7 +585,10 @@ static void _zh_wifi_event_handler(void *arg, esp_event_base_t event_base, int32
     case WIFI_EVENT_STA_DISCONNECTED:
         if (_is_wifi_connected == true)
         {
-            vTaskDelete(_zh_stats_task_handle);
+            if (_zh_stats_task_handle != NULL)
+            {
+                vTaskDelete(_zh_stats_task_handle);
+            }
             zh_syslog_deinit();
             _is_wifi_connected = false;
         }
@@ -364,7 +604,11 @@ static void _zh_wifi_event_handler(void *arg, esp_event_base_t event_base, int32
         zh_syslog_init_config_t config = ZH_SYSLOG_INIT_CONFIG_DEFAULT();
         strcpy(config.syslog_ip, SYSLOG_IP);
         zh_syslog_init(&config);
-        xTaskCreatePinnedToCore(&_zh_stats_processing_task, "stats_processing_task", STATS_TASK_STACK_SIZE, NULL, STATS_TASK_PRIORITY, &_zh_stats_task_handle, tskNO_AFFINITY);
+        if (_zh_stats_task_handle == NULL)
+        {
+            xTaskCreatePinnedToCore(&_zh_stats_processing_task, "stats_processing_task", STATS_TASK_STACK_SIZE, NULL, STATS_TASK_PRIORITY,
+                                    &_zh_stats_task_handle, tskNO_AFFINITY);
+        }
         break;
     default:
         break;
@@ -373,6 +617,7 @@ static void _zh_wifi_event_handler(void *arg, esp_event_base_t event_base, int32
 
 static void _zh_inclinometer_reset_timer_on_alarm_cb(void *arg)
 {
+    (void)arg;
     _is_reset_mode = false;
     _is_reset_occurred = true;
     if (_is_menu_mode == false)
@@ -394,11 +639,13 @@ static void _zh_inclinometer_reset_timer_on_alarm_cb(void *arg)
 
 static void _zh_a_inclinometer_processing_task(void *pvParameter)
 {
-    float prev_angle = 0, current_angle = 0;
+    (void)pvParameter;
+    float prev_angle = 0.0;
+    float current_angle = 0.0;
     xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-    zh_160x_set_cursor(&_lcd_handle, 1, 0);
-    zh_160x_print_char(&_lcd_handle, "A:");
-    zh_160x_print_float(&_lcd_handle, current_angle, 1);
+    zh_160x_set_cursor(&_lcd_160x_handle, 1, 0);
+    zh_160x_print_char(&_lcd_160x_handle, "A:");
+    zh_160x_print_float(&_lcd_160x_handle, current_angle, 1);
     xSemaphoreGive(_lcd_mutex);
     for (;;)
     {
@@ -407,10 +654,10 @@ static void _zh_a_inclinometer_processing_task(void *pvParameter)
         {
             prev_angle = current_angle;
             xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-            zh_160x_set_cursor(&_lcd_handle, 1, 5);
-            zh_160x_print_char(&_lcd_handle, "   ");
-            zh_160x_set_cursor(&_lcd_handle, 1, 2);
-            zh_160x_print_float(&_lcd_handle, current_angle, 1);
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 5);
+            zh_160x_print_char(&_lcd_160x_handle, "   ");
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 2);
+            zh_160x_print_float(&_lcd_160x_handle, current_angle, 1);
             xSemaphoreGive(_lcd_mutex);
         }
         vTaskDelay(100 / portTICK_PERIOD_MS);
@@ -421,11 +668,13 @@ static void _zh_a_inclinometer_processing_task(void *pvParameter)
 
 static void _zh_b_inclinometer_processing_task(void *pvParameter)
 {
-    float prev_angle = 0, current_angle = 0;
+    (void)pvParameter;
+    float prev_angle = 0.0;
+    float current_angle = 0.0;
     xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-    zh_160x_set_cursor(&_lcd_handle, 1, 8);
-    zh_160x_print_char(&_lcd_handle, "B:");
-    zh_160x_print_float(&_lcd_handle, current_angle, 1);
+    zh_160x_set_cursor(&_lcd_160x_handle, 1, 8);
+    zh_160x_print_char(&_lcd_160x_handle, "B:");
+    zh_160x_print_float(&_lcd_160x_handle, current_angle, 1);
     xSemaphoreGive(_lcd_mutex);
     for (;;)
     {
@@ -434,10 +683,10 @@ static void _zh_b_inclinometer_processing_task(void *pvParameter)
         {
             prev_angle = current_angle;
             xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-            zh_160x_set_cursor(&_lcd_handle, 1, 13);
-            zh_160x_print_char(&_lcd_handle, "   ");
-            zh_160x_set_cursor(&_lcd_handle, 1, 10);
-            zh_160x_print_float(&_lcd_handle, current_angle, 1);
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 13);
+            zh_160x_print_char(&_lcd_160x_handle, "   ");
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 10);
+            zh_160x_print_float(&_lcd_160x_handle, current_angle, 1);
             xSemaphoreGive(_lcd_mutex);
         }
         vTaskDelay(100 / portTICK_PERIOD_MS);
@@ -448,11 +697,13 @@ static void _zh_b_inclinometer_processing_task(void *pvParameter)
 
 static void _zh_a_tachometer_processing_task(void *pvParameter)
 {
-    uint16_t prev_rpm = 0, current_rpm = 0;
+    (void)pvParameter;
+    uint16_t prev_rpm = 0;
+    uint16_t current_rpm = 0;
     xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-    zh_160x_set_cursor(&_lcd_handle, 1, 0);
-    zh_160x_print_char(&_lcd_handle, "A:");
-    zh_160x_print_int(&_lcd_handle, current_rpm);
+    zh_160x_set_cursor(&_lcd_160x_handle, 1, 0);
+    zh_160x_print_char(&_lcd_160x_handle, "A:");
+    zh_160x_print_int(&_lcd_160x_handle, current_rpm);
     xSemaphoreGive(_lcd_mutex);
     for (;;)
     {
@@ -461,10 +712,10 @@ static void _zh_a_tachometer_processing_task(void *pvParameter)
         {
             prev_rpm = current_rpm;
             xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-            zh_160x_set_cursor(&_lcd_handle, 1, 3);
-            zh_160x_print_char(&_lcd_handle, "    ");
-            zh_160x_set_cursor(&_lcd_handle, 1, 2);
-            zh_160x_print_int(&_lcd_handle, current_rpm);
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 3);
+            zh_160x_print_char(&_lcd_160x_handle, "    ");
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 2);
+            zh_160x_print_int(&_lcd_160x_handle, current_rpm);
             xSemaphoreGive(_lcd_mutex);
         }
         vTaskDelay(100 / portTICK_PERIOD_MS);
@@ -475,11 +726,13 @@ static void _zh_a_tachometer_processing_task(void *pvParameter)
 
 static void _zh_b_tachometer_processing_task(void *pvParameter)
 {
-    uint16_t prev_rpm = 0, current_rpm = 0;
+    (void)pvParameter;
+    uint16_t prev_rpm = 0;
+    uint16_t current_rpm = 0;
     xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-    zh_160x_set_cursor(&_lcd_handle, 1, 8);
-    zh_160x_print_char(&_lcd_handle, "B:");
-    zh_160x_print_int(&_lcd_handle, current_rpm);
+    zh_160x_set_cursor(&_lcd_160x_handle, 1, 8);
+    zh_160x_print_char(&_lcd_160x_handle, "B:");
+    zh_160x_print_int(&_lcd_160x_handle, current_rpm);
     xSemaphoreGive(_lcd_mutex);
     for (;;)
     {
@@ -488,10 +741,10 @@ static void _zh_b_tachometer_processing_task(void *pvParameter)
         {
             prev_rpm = current_rpm;
             xSemaphoreTake(_lcd_mutex, portMAX_DELAY);
-            zh_160x_set_cursor(&_lcd_handle, 1, 11);
-            zh_160x_print_char(&_lcd_handle, "    ");
-            zh_160x_set_cursor(&_lcd_handle, 1, 10);
-            zh_160x_print_int(&_lcd_handle, current_rpm);
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 11);
+            zh_160x_print_char(&_lcd_160x_handle, "    ");
+            zh_160x_set_cursor(&_lcd_160x_handle, 1, 10);
+            zh_160x_print_int(&_lcd_160x_handle, current_rpm);
             xSemaphoreGive(_lcd_mutex);
         }
         vTaskDelay(100 / portTICK_PERIOD_MS);
@@ -502,51 +755,52 @@ static void _zh_b_tachometer_processing_task(void *pvParameter)
 
 static void _zh_stats_processing_task(void *pvParameter)
 {
+    (void)pvParameter;
     const esp_app_desc_t *esp_app_desc = esp_app_get_description();
     for (;;)
     {
         char buffer[1024] = {0};
         const zh_encoder_stats_t *encoder_stats = zh_encoder_get_stats();
         const zh_pcf8574_stats_t *pcf8574_stats = zh_pcf8574_get_stats();
-        sprintf(buffer, "A inclinometer task minimum free stack size: %ld.\n", _task_stats.a_inclinometer_task_min_stack_size);
+        snprintf(buffer, sizeof(buffer), "A inclinometer task minimum free stack size: %lu.\n", _task_stats.a_inclinometer_task_min_stack_size);
         zh_syslog_send(ZH_KERN, _task_stats.a_inclinometer_task_min_stack_size > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_inclinometer", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "B inclinometer task minimum free stack size: %ld.\n", _task_stats.b_inclinometer_task_min_stack_size);
+        snprintf(buffer, sizeof(buffer), "B inclinometer task minimum free stack size: %lu.\n", _task_stats.b_inclinometer_task_min_stack_size);
         zh_syslog_send(ZH_KERN, _task_stats.b_inclinometer_task_min_stack_size > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_inclinometer", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "A tachometer task minimum free stack size: %ld.\n", _task_stats.b_tachometer_task_min_stack_size);
+        snprintf(buffer, sizeof(buffer), "A tachometer task minimum free stack size: %lu.\n", _task_stats.a_tachometer_task_min_stack_size);
+        zh_syslog_send(ZH_KERN, _task_stats.a_tachometer_task_min_stack_size > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_tachometer", buffer);
+        vTaskDelay(500 / portTICK_PERIOD_MS);
+        snprintf(buffer, sizeof(buffer), "B tachometer task minimum free stack size: %lu.\n", _task_stats.b_tachometer_task_min_stack_size);
         zh_syslog_send(ZH_KERN, _task_stats.b_tachometer_task_min_stack_size > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_tachometer", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "B tachometer task minimum free stack size: %ld.\n", _task_stats.b_tachometer_task_min_stack_size);
-        zh_syslog_send(ZH_KERN, _task_stats.b_tachometer_task_min_stack_size > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_tachometer", buffer);
-        vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Stats task minimum free stack size: %ld.\n", (uint32_t)uxTaskGetStackHighWaterMark(NULL));
+        snprintf(buffer, sizeof(buffer), "Stats task minimum free stack size: %lu.\n", (uint32_t)uxTaskGetStackHighWaterMark(NULL));
         zh_syslog_send(ZH_KERN, (uint32_t)uxTaskGetStackHighWaterMark(NULL) > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_syslog", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Encoder task minimum free stack size: %ld.\n", encoder_stats->min_stack_size);
+        snprintf(buffer, sizeof(buffer), "Encoder task minimum free stack size: %lu.\n", encoder_stats->min_stack_size);
         zh_syslog_send(ZH_KERN, encoder_stats->min_stack_size > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_encoder", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Expander task minimum free stack size: %ld.\n", pcf8574_stats->min_stack_size);
+        snprintf(buffer, sizeof(buffer), "Expander task minimum free stack size: %lu.\n", pcf8574_stats->min_stack_size);
         zh_syslog_send(ZH_KERN, pcf8574_stats->min_stack_size > 100 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_pcf8574", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Number of event post error: %ld.\n", encoder_stats->event_post_error);
+        snprintf(buffer, sizeof(buffer), "Number of event post error: %lu.\n", encoder_stats->event_post_error);
         zh_syslog_send(ZH_KERN, encoder_stats->event_post_error == 0 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_encoder", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Number of queue overflow error: %ld.\n", encoder_stats->queue_overflow_error);
+        snprintf(buffer, sizeof(buffer), "Number of queue overflow error: %lu.\n", encoder_stats->queue_overflow_error);
         zh_syslog_send(ZH_KERN, encoder_stats->queue_overflow_error == 0 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_encoder", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Number of i2c driver error: %ld.\n", pcf8574_stats->i2c_driver_error);
+        snprintf(buffer, sizeof(buffer), "Number of i2c driver error: %lu.\n", pcf8574_stats->i2c_driver_error);
         zh_syslog_send(ZH_KERN, pcf8574_stats->i2c_driver_error == 0 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_pcf8574", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Number of event post error: %ld.\n", pcf8574_stats->event_post_error);
+        snprintf(buffer, sizeof(buffer), "Number of event post error: %lu.\n", pcf8574_stats->event_post_error);
         zh_syslog_send(ZH_KERN, pcf8574_stats->event_post_error == 0 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_pcf8574", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Number of vector error: %ld.\n", pcf8574_stats->vector_error);
+        snprintf(buffer, sizeof(buffer), "Number of vector error: %lu.\n", pcf8574_stats->vector_error);
         zh_syslog_send(ZH_KERN, pcf8574_stats->vector_error == 0 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_pcf8574", buffer);
         vTaskDelay(500 / portTICK_PERIOD_MS);
-        sprintf(buffer, "Number of queue overflow error: %ld.\n", pcf8574_stats->queue_overflow_error);
+        snprintf(buffer, sizeof(buffer), "Number of queue overflow error: %lu.\n", pcf8574_stats->queue_overflow_error);
         zh_syslog_send(ZH_KERN, pcf8574_stats->queue_overflow_error == 0 ? ZH_INFO : ZH_WARNING, esp_app_desc->project_name, "zh_pcf8574", buffer);
         vTaskDelay(60000 / portTICK_PERIOD_MS);
     }
     vTaskDelete(NULL);
-}
+}