Added SNTP and start of data logging

components/wifi/CMakeLists.txt

@@ -1,4 +1,4 @@
 idf_component_register(SRCS "wifi.c"
   INCLUDE_DIRS "."
-  REQUIRES driver esp_wifi
+  REQUIRES driver esp_wifi lwip
 )

components/wifi/wifi.c

@@ -1,17 +1,28 @@
+#include "wifi.h"
 #include <string.h>
-
-#include "esp_system.h"
+#include "freertos/FreeRTOS.h"
+#include "esp_sntp.h"
 #include "esp_wifi.h"
 #include "esp_event.h"
 #include "esp_log.h"
 
-static const char* TAG = "WIFI";
+static const char *TAG = "WIFI";
+
+static EventGroupHandle_t s_wifi_event_group;
+static bool ntp_time_obtained = false;
+
+#define WIFI_CONNECTED_BIT (1 << 0)
+
+bool has_ntp_time_obtained_once() {
+  return ntp_time_obtained;
+}
 
 static void event_handler(void* arg, esp_event_base_t event_base,
                                 int32_t event_id, void* event_data)
 {
     if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
       esp_wifi_connect();
+      ESP_LOGI(TAG, "connecting...");
     }
     else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
         esp_wifi_connect();
@@ -20,11 +31,11 @@ static void event_handler(void* arg, esp_event_base_t event_base,
     else if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
         ip_event_got_ip_t* event = (ip_event_got_ip_t*) event_data;
         ESP_LOGI(TAG, "got ip:" IPSTR, IP2STR(&event->ip_info.ip));
+        xEventGroupSetBits(s_wifi_event_group, WIFI_CONNECTED_BIT);
     }
 }
 
 void start_wifi() {
-
     ESP_ERROR_CHECK(esp_netif_init());
 
     ESP_ERROR_CHECK(esp_event_loop_create_default());
@@ -33,6 +44,8 @@ void start_wifi() {
     wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
     ESP_ERROR_CHECK(esp_wifi_init(&cfg));
 
+    s_wifi_event_group = xEventGroupCreate();
+
     esp_event_handler_instance_t instance_any_id;
     esp_event_handler_instance_t instance_got_ip;
     ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT,
@@ -58,4 +71,30 @@ void start_wifi() {
     ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config) );
     ESP_ERROR_CHECK(esp_wifi_start() );
     ESP_LOGI(TAG, "wifi_init_sta finished.");
+
+    // Wait for WiFi to connect
+    xEventGroupWaitBits(s_wifi_event_group, WIFI_CONNECTED_BIT, pdFALSE, pdFALSE, portMAX_DELAY);
+    esp_sntp_setservername(0, "pool.ntp.org");
+    esp_sntp_setoperatingmode(SNTP_OPMODE_POLL);
+    sntp_set_sync_status(SNTP_SYNC_STATUS_RESET);
+    sntp_set_sync_mode(SNTP_SYNC_MODE_SMOOTH);
+    esp_sntp_init();
+
+    setenv("TZ", "GMT0BST,M3.5.0/1,M10.5.0", 1);
+    tzset();
+
+
+    for (uint32_t i = 0; i < 20; ++i) {
+        if (sntp_get_sync_status() != SNTP_SYNC_STATUS_COMPLETED) {
+           ESP_LOGI(TAG, "... waiting for time update");
+           vTaskDelay(1000 / portTICK_PERIOD_MS);
+        }
+    }
+
+    time_t epoch;
+    time(&epoch);
+    struct tm *timeinfo = localtime(&epoch);
+
+    ESP_LOGI(TAG, "Current time: %i:%i", timeinfo->tm_hour, timeinfo->tm_min);
+    ntp_time_obtained = true;
 }

components/wifi/wifi.h

@@ -1,3 +1,12 @@
 #pragma once
 
+#include <stdbool.h>
+// The idea with this function is to check if NTP time has been obtained
+// at least once - and therefore time is at least vaguely accurate
+// I want to call this when saving data to know whether the time is valid/trusted
+// at all
+bool has_ntp_time_obtained_once();
+
+// Probably should rename this to "start networking" or something because
+// it also does NTP stuff, and maybe even establish the HTTP Server stuff?
 void start_wifi();

main/main.c

@@ -7,13 +7,14 @@
 #include "dht22.h"
 #include "wifi.h"
 #include "esp_log.h"
-#include "esp_wifi.h"
+#include "esp_sntp.h"
 #include "freertos/FreeRTOS.h"
 #include "freertos/projdefs.h"
 #include "freertos/task.h"
 #include "nvs_flash.h"
 #include "portmacro.h"
 #include <stdbool.h>
+#include <stdint.h>
 #include <stdio.h>
 
 static const char* TAG = "YASPAM";
@@ -24,6 +25,15 @@ static volatile bool run_pms5003 = true;
 static TaskHandle_t dht22_handle = NULL;
 static TaskHandle_t pms5003_handle = NULL;
 
+typedef struct {
+  uint8_t myt_sec;    // 0 -> 61
+  uint8_t myt_min;    // 0 -> 69
+  uint8_t myt_hour;   // 0 -> 23
+  uint8_t myt_day;    // 1 -> 31
+  uint8_t myt_month;  // 0 -> 11 !!
+  uint8_t myt_year;   // years since 1900
+} my_time;
+
 #ifdef CONFIG_PMS5003_ENABLED
 #include "pms5003.h"
 
@@ -42,19 +52,48 @@ read_from_pms5003()
 #ifdef CONFIG_DHT22_ENABLED
 #include "dht22.h"
 
-void
-read_from_dht22()
-{
+typedef struct {
+  deci_percent rh;
+  deci_degrees_c temp;
+  my_time time;
+} my_dht22_data;
+
+my_dht22_data latest_datapoint;
+
+my_dht22_data ten_minute_rolling_average;
+uint16_t num_samples_last_ten_mins = 0;
+
+void read_from_dht22() {
   while (run_dht) {
     // Data reading is based on time, so need to block interrups etc
+    // I _think_ these are freeRTOS task interrupts - I wonder if
+    // I need to also block ESP interrupts? Should I even do that?
     portDISABLE_INTERRUPTS();
     int ret = dht22_read();
     portENABLE_INTERRUPTS();
     if (ret != DHT22_OK) {
       dht22_handle_error(ret);
     } else {
-      ESP_LOGI(TAG, "Got DHT22 data!");
-      // TODO: Write the data out somewhere - into RAM maybe?
+      latest_datapoint.temp = dht22_temperature();
+      latest_datapoint.rh = dht22_relative_humidity();
+
+      if (has_ntp_time_obtained_once()) {
+        time_t epoch;
+        time(&epoch);
+        struct tm *timeinfo = localtime(&epoch);
+
+        // There must be a better way - I couldn't figure out how to do it nicely all at once
+        latest_datapoint.time.myt_sec   = timeinfo->tm_sec;
+        latest_datapoint.time.myt_min   = timeinfo->tm_min;
+        latest_datapoint.time.myt_hour  = timeinfo->tm_hour;
+        latest_datapoint.time.myt_day   = timeinfo->tm_mday;
+        latest_datapoint.time.myt_month = timeinfo->tm_mon;
+        latest_datapoint.time.myt_year = timeinfo->tm_year;
+        // TODO: update ten minute rolling average
+        //
+        // TODO: Write the data out somewhere - into RAM maybe - I think only every 10 minutes
+        // though
+      }
     }
     vTaskDelay(pdMS_TO_TICKS(CONFIG_DHT22_PERIOD_POLL));
   }