examples/protocols/sntp: use common network component

examples/protocols/sntp/CMakeLists.txt

@@ -2,5 +2,9 @@
 # in this exact order for cmake to work correctly
 cmake_minimum_required(VERSION 3.5)
 
+# (Not part of the boilerplate)
+# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
+set(EXTRA_COMPONENT_DIRS $ENV{IDF_PATH}/examples/common_components/protocol_examples_common)
+
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 project(sntp)

examples/protocols/sntp/Makefile

@@ -5,5 +5,7 @@
 
 PROJECT_NAME := sntp
 
+EXTRA_COMPONENT_DIRS = $(IDF_PATH)/examples/common_components/protocol_examples_common
+
 include $(IDF_PATH)/make/project.mk
 

examples/protocols/sntp/README.md

@@ -2,6 +2,14 @@
 
 This example demonstrates the use of LwIP SNTP module to obtain time from Internet servers. See the README.md file in the upper level 'examples' directory for more information about examples.
 
+## Configuring the Example
+
+To configure the project, run `make menuconfig` (or `idf.py menuconfig` if using CMake build system).
+
+* Configure Wi-Fi or Ethernet under "Example Connection Configuration" menu. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../README.md) for more details.
+
+* When using Make build system, set `Default serial port` under `Serial flasher config`.
+
 ## Obtaining time using LwIP SNTP module
 
 When this example boots first time after ESP32 is reset, it connects to WiFi and obtains time using SNTP.

examples/protocols/sntp/main/Kconfig.projbuild

@@ -1,17 +0,0 @@
-menu "Example Configuration"
-
-    config WIFI_SSID
-        string "WiFi SSID"
-        default "myssid"
-        help
-            SSID (network name) for the example to connect to.
-
-    config WIFI_PASSWORD
-        string "WiFi Password"
-        default "mypassword"
-        help
-            WiFi password (WPA or WPA2) for the example to use.
-
-            Can be left blank if the network has no security set.
-
-endmenu

examples/protocols/sntp/main/sntp_example_main.c

@@ -13,33 +13,16 @@
 #include "freertos/task.h"
 #include "freertos/event_groups.h"
 #include "esp_system.h"
-#include "esp_wifi.h"
+#include "esp_event.h"
-#include "esp_event_loop.h"
 #include "esp_log.h"
 #include "esp_attr.h"
 #include "esp_sleep.h"
 #include "nvs_flash.h"
+#include "protocol_examples_common.h"
 
 #include "lwip/err.h"
 #include "lwip/apps/sntp.h"
 
-/* The examples use simple WiFi configuration that you can set via
-   'make menuconfig'.
-
-   If you'd rather not, just change the below entries to strings with
-   the config you want - ie #define EXAMPLE_WIFI_SSID "mywifissid"
-*/
-#define EXAMPLE_WIFI_SSID CONFIG_WIFI_SSID
-#define EXAMPLE_WIFI_PASS CONFIG_WIFI_PASSWORD
-
-/* FreeRTOS event group to signal when we are connected & ready to make a request */
-static EventGroupHandle_t wifi_event_group;
-
-/* The event group allows multiple bits for each event,
-   but we only care about one event - are we connected
-   to the AP with an IP? */
-const int CONNECTED_BIT = BIT0;
-
 static const char *TAG = "example";
 
 /* Variable holding number of times ESP32 restarted since first boot.
@@ -50,8 +33,6 @@ RTC_DATA_ATTR static int boot_count = 0;
 
 static void obtain_time(void);
 static void initialize_sntp(void);
-static void initialise_wifi(void);
-static esp_err_t event_handler(void *ctx, system_event_t *event);
 
 
 void app_main()
@@ -94,9 +75,15 @@ void app_main()
 static void obtain_time(void)
 {
     ESP_ERROR_CHECK( nvs_flash_init() );
-    initialise_wifi();
+    tcpip_adapter_init();
-    xEventGroupWaitBits(wifi_event_group, CONNECTED_BIT,
+    ESP_ERROR_CHECK( esp_event_loop_create_default() );
-                        false, true, portMAX_DELAY);
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+
     initialize_sntp();
 
     // wait for time to be set
@@ -111,7 +98,7 @@ static void obtain_time(void)
         localtime_r(&now, &timeinfo);
     }
 
-    ESP_ERROR_CHECK( esp_wifi_stop() );
+    ESP_ERROR_CHECK( example_disconnect() );
 }
 
 static void initialize_sntp(void)
@@ -121,44 +108,3 @@ static void initialize_sntp(void)
     sntp_setservername(0, "pool.ntp.org");
     sntp_init();
 }
-
-static void initialise_wifi(void)
-{
-    tcpip_adapter_init();
-    wifi_event_group = xEventGroupCreate();
-    ESP_ERROR_CHECK( esp_event_loop_init(event_handler, NULL) );
-    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
-    ESP_ERROR_CHECK( esp_wifi_init(&cfg) );
-    ESP_ERROR_CHECK( esp_wifi_set_storage(WIFI_STORAGE_RAM) );
-    wifi_config_t wifi_config = {
-        .sta = {
-            .ssid = EXAMPLE_WIFI_SSID,
-            .password = EXAMPLE_WIFI_PASS,
-        },
-    };
-    ESP_LOGI(TAG, "Setting WiFi configuration SSID %s...", wifi_config.sta.ssid);
-    ESP_ERROR_CHECK( esp_wifi_set_mode(WIFI_MODE_STA) );
-    ESP_ERROR_CHECK( esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config) );
-    ESP_ERROR_CHECK( esp_wifi_start() );
-}
-
-static esp_err_t event_handler(void *ctx, system_event_t *event)
-{
-    switch(event->event_id) {
-    case SYSTEM_EVENT_STA_START:
-        esp_wifi_connect();
-        break;
-    case SYSTEM_EVENT_STA_GOT_IP:
-        xEventGroupSetBits(wifi_event_group, CONNECTED_BIT);
-        break;
-    case SYSTEM_EVENT_STA_DISCONNECTED:
-        /* This is a workaround as ESP32 WiFi libs don't currently
-           auto-reassociate. */
-        esp_wifi_connect();
-        xEventGroupClearBits(wifi_event_group, CONNECTED_BIT);
-        break;
-    default:
-        break;
-    }
-    return ESP_OK;
-}