diff --git a/main/ate0004.c b/main/ate0004.c
index bfb1c77..aed4cd5 100644
--- a/main/ate0004.c
+++ b/main/ate0004.c
@@ -1,37 +1,37 @@
 #include "ate0004.h"
 
-static i2c_master_bus_handle_t i2c_bus_handle = NULL;
-static httpd_handle_t webserver_handle = NULL;
+static i2c_master_bus_handle_t _i2c_bus_handle = NULL;
+static httpd_handle_t _webserver_handle = NULL;
 
-static zh_pcf8574_handle_t button_handle = {0};
-static zh_pcf8574_handle_t led_handle = {0};
-static zh_pcf8574_handle_t relay_handle = {0};
+static zh_pcf8574_handle_t _button_handle = {0};
+static zh_pcf8574_handle_t _led_handle = {0};
+static zh_pcf8574_handle_t _relay_handle = {0};
 
-static bool is_ts = true;
-static bool is_ret = false;
-static bool is_ext = false;
+static bool _is_ts_enabled = true;
+static bool _is_ret_enabled = false;
+static bool _is_ext_enabled = false;
 
-static void zh_wifi_softap_init(void);
-static void zh_webserver_init(void);
-static void zh_gpio_init(void);
-static void zh_io_expander_init(void);
-static void zh_pcf8574_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
+static void _zh_wifi_softap_init(void);
+static void _zh_webserver_init(void);
+static void _zh_gpio_init(void);
+static void _zh_pcf8574_init(void);
+static void _zh_pcf8574_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
 
 void app_main(void)
 {
     nvs_flash_init();
     esp_event_loop_create_default();
-    zh_wifi_softap_init();
-    zh_webserver_init();
-    zh_gpio_init();
+    _zh_wifi_softap_init();
+    _zh_webserver_init();
+    _zh_gpio_init();
     gpio_set_level(TRIAC_GPIO, LOW);
-    zh_io_expander_init();
-    zh_pcf8574_write_gpio(&led_handle, TS_LED_GREEN, LED_ON);
-    zh_pcf8574_write_gpio(&led_handle, RET_LED_BLUE, LED_ON);
-    zh_pcf8574_write_gpio(&led_handle, EXT_LED_BLUE, LED_ON);
+    _zh_pcf8574_init();
+    zh_pcf8574_write_gpio(&_led_handle, TS_LED_GREEN, LED_ON);
+    zh_pcf8574_write_gpio(&_led_handle, RET_LED_BLUE, LED_ON);
+    zh_pcf8574_write_gpio(&_led_handle, EXT_LED_BLUE, LED_ON);
 }
 
-static void zh_wifi_softap_init(void)
+static void _zh_wifi_softap_init(void)
 {
     esp_netif_init();
     esp_netif_create_default_wifi_ap();
@@ -50,14 +50,14 @@ static void zh_wifi_softap_init(void)
     esp_wifi_start();
 }
 
-static void zh_webserver_init(void)
+static void _zh_webserver_init(void)
 {
     httpd_config_t config = HTTPD_DEFAULT_CONFIG();
-    httpd_start(&webserver_handle, &config);
-    zh_ota_server_init(webserver_handle);
+    httpd_start(&_webserver_handle, &config);
+    zh_ota_server_init(_webserver_handle);
 }
 
-static void zh_gpio_init(void)
+static void _zh_gpio_init(void)
 {
     gpio_config_t triac_pin_config = {
         .intr_type = GPIO_INTR_DISABLE,
@@ -69,7 +69,7 @@ static void zh_gpio_init(void)
     gpio_config(&triac_pin_config);
 }
 
-static void zh_io_expander_init(void)
+static void _zh_pcf8574_init(void)
 {
     i2c_master_bus_config_t i2c_bus_config = {
         .clk_source = I2C_CLK_SRC_DEFAULT,
@@ -77,96 +77,96 @@ static void zh_io_expander_init(void)
         .sda_io_num = GPIO_NUM_21,
         .glitch_ignore_cnt = 7,
     };
-    i2c_new_master_bus(&i2c_bus_config, &i2c_bus_handle);
-    esp_event_handler_instance_register(ZH_PCF8574, ESP_EVENT_ANY_ID, &zh_pcf8574_event_handler, NULL, NULL);
+    i2c_new_master_bus(&i2c_bus_config, &_i2c_bus_handle);
+    esp_event_handler_instance_register(ZH_PCF8574, ESP_EVENT_ANY_ID, &_zh_pcf8574_event_handler, NULL, NULL);
     zh_pcf8574_init_config_t config = ZH_PCF8574_INIT_CONFIG_DEFAULT();
-    config.i2c_handle = i2c_bus_handle;
+    config.i2c_handle = _i2c_bus_handle;
     config.i2c_address = LED_I2C_ADDRESS;
-    zh_pcf8574_init(&config, &led_handle);
+    zh_pcf8574_init(&config, &_led_handle);
     config.i2c_address = RELAY_I2C_ADDRESS;
-    zh_pcf8574_init(&config, &relay_handle);
+    zh_pcf8574_init(&config, &_relay_handle);
     config.i2c_address = BUTTON_I2C_ADDRESS;
     config.p0_gpio_work_mode = true;
     config.p1_gpio_work_mode = true;
     config.p2_gpio_work_mode = true;
     config.interrupt_gpio = GPIO_NUM_17;
-    zh_pcf8574_init(&config, &button_handle);
+    zh_pcf8574_init(&config, &_button_handle);
 }
 
-static void zh_pcf8574_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
+static void _zh_pcf8574_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
 {
     zh_pcf8574_event_on_isr_t *event = event_data;
     switch (event->gpio_number)
     {
     case TS_BUTTON:
-        if (event->gpio_level == LOW && is_ret == false && is_ext == false)
+        if (event->gpio_level == LOW && _is_ret_enabled == false && _is_ext_enabled == false)
         {
-            if (is_ts == true)
+            if (_is_ts_enabled == true)
             {
-                zh_pcf8574_write_gpio(&led_handle, TS_LED_RED, LED_ON);
-                zh_pcf8574_write_gpio(&led_handle, TS_LED_GREEN, LED_OFF);
-                zh_pcf8574_write_gpio(&relay_handle, TS_RELAY, RELAY_ON);
-                is_ts = false;
+                zh_pcf8574_write_gpio(&_led_handle, TS_LED_RED, LED_ON);
+                zh_pcf8574_write_gpio(&_led_handle, TS_LED_GREEN, LED_OFF);
+                zh_pcf8574_write_gpio(&_relay_handle, TS_RELAY, RELAY_ON);
+                _is_ts_enabled = false;
             }
             else
             {
-                zh_pcf8574_write_gpio(&led_handle, TS_LED_RED, LED_OFF);
-                zh_pcf8574_write_gpio(&led_handle, TS_LED_GREEN, LED_ON);
-                zh_pcf8574_write_gpio(&relay_handle, TS_RELAY, RELAY_OFF);
-                is_ts = true;
+                zh_pcf8574_write_gpio(&_led_handle, TS_LED_RED, LED_OFF);
+                zh_pcf8574_write_gpio(&_led_handle, TS_LED_GREEN, LED_ON);
+                zh_pcf8574_write_gpio(&_relay_handle, TS_RELAY, RELAY_OFF);
+                _is_ts_enabled = true;
             }
         }
         break;
     case RET_BUTTON:
-        if (is_ext == true)
+        if (_is_ext_enabled == true)
         {
             break;
         }
         if (event->gpio_level == LOW)
         {
-            is_ret = true;
-            zh_pcf8574_write_gpio(&led_handle, RET_LED_BLUE, LED_OFF);
-            zh_pcf8574_write_gpio(&led_handle, RET_LED_GREEN, LED_ON);
-            zh_pcf8574_write_gpio(&relay_handle, RET_RELAY, RELAY_ON);
-            zh_pcf8574_write_gpio(&relay_handle, GROUND_RELAY, RELAY_ON);
+            _is_ret_enabled = true;
+            zh_pcf8574_write_gpio(&_led_handle, RET_LED_BLUE, LED_OFF);
+            zh_pcf8574_write_gpio(&_led_handle, RET_LED_GREEN, LED_ON);
+            zh_pcf8574_write_gpio(&_relay_handle, RET_RELAY, RELAY_ON);
+            zh_pcf8574_write_gpio(&_relay_handle, GROUND_RELAY, RELAY_ON);
             vTaskDelay(20 / portTICK_PERIOD_MS);
             gpio_set_level(TRIAC_GPIO, HIGH);
         }
         else
         {
             gpio_set_level(TRIAC_GPIO, LOW);
-            vTaskDelay(1 / portTICK_PERIOD_MS);
-            zh_pcf8574_write_gpio(&led_handle, RET_LED_BLUE, LED_ON);
-            zh_pcf8574_write_gpio(&led_handle, RET_LED_GREEN, LED_OFF);
-            zh_pcf8574_write_gpio(&relay_handle, RET_RELAY, RELAY_OFF);
-            zh_pcf8574_write_gpio(&relay_handle, GROUND_RELAY, RELAY_OFF);
-            is_ret = false;
+            vTaskDelay(5 / portTICK_PERIOD_MS);
+            zh_pcf8574_write_gpio(&_led_handle, RET_LED_BLUE, LED_ON);
+            zh_pcf8574_write_gpio(&_led_handle, RET_LED_GREEN, LED_OFF);
+            zh_pcf8574_write_gpio(&_relay_handle, RET_RELAY, RELAY_OFF);
+            zh_pcf8574_write_gpio(&_relay_handle, GROUND_RELAY, RELAY_OFF);
+            _is_ret_enabled = false;
         }
         break;
     case EXT_BUTTON:
-        if (is_ret == true)
+        if (_is_ret_enabled == true)
         {
             break;
         }
         if (event->gpio_level == LOW)
         {
-            is_ext = true;
-            zh_pcf8574_write_gpio(&led_handle, EXT_LED_BLUE, LED_OFF);
-            zh_pcf8574_write_gpio(&led_handle, EXT_LED_GREEN, LED_ON);
-            zh_pcf8574_write_gpio(&relay_handle, EXT_RELAY, RELAY_ON);
-            zh_pcf8574_write_gpio(&relay_handle, GROUND_RELAY, RELAY_ON);
+            _is_ext_enabled = true;
+            zh_pcf8574_write_gpio(&_led_handle, EXT_LED_BLUE, LED_OFF);
+            zh_pcf8574_write_gpio(&_led_handle, EXT_LED_GREEN, LED_ON);
+            zh_pcf8574_write_gpio(&_relay_handle, EXT_RELAY, RELAY_ON);
+            zh_pcf8574_write_gpio(&_relay_handle, GROUND_RELAY, RELAY_ON);
             vTaskDelay(20 / portTICK_PERIOD_MS);
             gpio_set_level(TRIAC_GPIO, HIGH);
         }
         else
         {
             gpio_set_level(TRIAC_GPIO, LOW);
-            vTaskDelay(1 / portTICK_PERIOD_MS);
-            zh_pcf8574_write_gpio(&led_handle, EXT_LED_BLUE, LED_ON);
-            zh_pcf8574_write_gpio(&led_handle, EXT_LED_GREEN, LED_OFF);
-            zh_pcf8574_write_gpio(&relay_handle, EXT_RELAY, RELAY_OFF);
-            zh_pcf8574_write_gpio(&relay_handle, GROUND_RELAY, RELAY_OFF);
-            is_ext = false;
+            vTaskDelay(5 / portTICK_PERIOD_MS);
+            zh_pcf8574_write_gpio(&_led_handle, EXT_LED_BLUE, LED_ON);
+            zh_pcf8574_write_gpio(&_led_handle, EXT_LED_GREEN, LED_OFF);
+            zh_pcf8574_write_gpio(&_relay_handle, EXT_RELAY, RELAY_OFF);
+            zh_pcf8574_write_gpio(&_relay_handle, GROUND_RELAY, RELAY_OFF);
+            _is_ext_enabled = false;
         }
         break;
     default:
diff --git a/main/ate0004.h b/main/ate0004.h
index be22b89..b2f2e45 100644
--- a/main/ate0004.h
+++ b/main/ate0004.h
@@ -1,3 +1,7 @@
+/**
+ * @file ate0004.h
+ */
+
 #pragma once
 
 #include "zh_pcf8574.h"