funktioniert.

CMakeLists.txt

@@ -32,6 +32,7 @@ add_custom_command(
 
 add_executable(sensor-pico
     src/main.cpp
+    src/time_sync.c
     src/webserver.c
 )
 
@@ -58,6 +59,7 @@ target_link_libraries(sensor-pico
     pico_lwip
     pico_lwip_http
     pico_lwip_mqtt
+    pico_lwip_sntp
 )
 
 # Erzeugt .uf2 Datei zum Flashen

lwipopts.h

@@ -1,6 +1,8 @@
 #ifndef _LWIPOPTS_H
 #define _LWIPOPTS_H
 
+#include <stdint.h>
+
 #define HTTPD_FSDATA_FILE "src/fsdata.c"
 
 #define NO_SYS 1
@@ -31,6 +33,20 @@
 #define PBUF_POOL_SIZE 24
 #define MEMP_NUM_SYS_TIMEOUT 20
 
+#define MQTT_OUTPUT_RINGBUF_SIZE 2048
+
+#define SNTP_SERVER_DNS 1
+#define SNTP_SERVER_ADDRESS "de.pool.ntp.org"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+void sntp_set_system_time_us(uint32_t sec, uint32_t us);
+#ifdef __cplusplus
+}
+#endif
+#define SNTP_SET_SYSTEM_TIME_US(sec, us) sntp_set_system_time_us((sec), (us))
+
 #define TCP_MSS 1460
 #define TCP_WND (8 * TCP_MSS)
 #define TCP_SND_BUF (8 * TCP_MSS)

src/main.cpp

@@ -3,12 +3,15 @@
 #include "hardware/i2c.h"
 #include "lwip/apps/httpd.h"
 #include "lwip/apps/mqtt.h"
+#include "lwip/apps/sntp.h"
 #include "pico/cyw43_arch.h"
 #include "pico/stdlib.h"
 #include "webserver.h"
-#include <cstdint>
 #include <cstdio>
+#include <cstdlib>
 #include <cstring>
+#include <ctime>
+#include <stdint.h>
 
 static dhcp_server_t dhcp_server{};
 
@@ -61,14 +64,14 @@ void mqtt_cb(mqtt_client_t *client, void *arg,
   *mqtt_status = (status == MQTT_CONNECT_ACCEPTED) ? 0 : 1;
 }
 
-int connect_to_mqtt() {
+mqtt_client_t *connect_to_mqtt() {
   static int mqtt_status{-1};
   ip_addr_t broker_ip;
   static mqtt_client_t *client{};
   static mqtt_connect_client_info_t info{};
 
   if (!ipaddr_aton(saved_mqtt_address, &broker_ip)) {
-    return -1;
+    return nullptr;
   }
   if (!client) {
     client = mqtt_client_new();
@@ -84,11 +87,14 @@ int connect_to_mqtt() {
     cyw43_arch_poll();
     sleep_ms(100);
   }
-  return mqtt_status;
+  if (mqtt_status == 0) {
+    return client;
+  }
+  return nullptr;
 }
 
 BME280_READING_INTERVALS_MS convert_Interval(int interval) {
-  if (interval < 1 && interval > 0) {
+  if (interval < 1) {
     return INTERVAL_0_5MS;
   } else if (interval < 20 && interval > 1) {
     return INTERVAL_10MS;
@@ -109,12 +115,100 @@ BME280_READING_INTERVALS_MS convert_Interval(int interval) {
   }
 }
 
+void publish_cb(void *arg, err_t err) { printf("Publish succesfull!\n"); }
+
+void publish_mqtt(mqtt_client_t *client, const char *payload) {
+  uint payload_len{strlen(payload)};
+  mqtt_publish(client, "tele/sensor-pico/SENSOR", payload, payload_len, 1, 1,
+               publish_cb, nullptr);
+}
+
+bool parse_json(const char *raw, float &temperature, float &humidity,
+                float &pressure) {
+  if (!raw)
+    return false;
+
+  const char *t_ptr = std::strstr(raw, "\"temperature\":");
+  const char *h_ptr = std::strstr(raw, "\"humidity\":");
+  const char *p_ptr = std::strstr(raw, "\"pressure\":");
+
+  if (!t_ptr || !h_ptr || !p_ptr)
+    return false;
+
+  long t_raw = std::strtol(t_ptr + 14, nullptr, 10);
+  long h_raw = std::strtol(h_ptr + 11, nullptr, 10);
+  long p_raw = std::strtol(p_ptr + 11, nullptr, 10);
+
+  temperature = t_raw / 100.0f;
+  humidity = h_raw / 1024.0f;
+  pressure = p_raw / 25600.0f;
+
+  return true;
+}
+
+void build_sensor_payload(char *buffer, size_t size, bme280_handle_t handle,
+                          const char *sensor_name) {
+  bme280_read_data(handle);
+  const char *raw = bme280_get_json(handle);
+
+  if (!raw) {
+    snprintf(buffer, size, "{\"error\":\"no data\"}");
+    return;
+  }
+
+  float temperature, humidity, pressure;
+  parse_json(raw, temperature, humidity, pressure);
+
+  time_t now;
+  time(&now);
+  struct tm *timeinfo = localtime(&now);
+
+  char time_str[32];
+  strftime(time_str, sizeof(time_str), "%Y-%m-%dT%H:%M:%S", timeinfo);
+
+  snprintf(buffer, size,
+           "{"
+           "\"Time\":\"%s\","
+           "\"%s\":{"
+           "\"Temperature\":%.2f,"
+           "\"Humidity\":%.2f,"
+           "\"Pressure\":%.2f"
+           "},"
+           "\"TempUnit\":\"C\""
+           "}",
+           time_str, sensor_name, temperature, humidity, pressure);
+}
+bool is_time_synced() {
+  time_t now = time(NULL);
+  struct tm *timeinfo = localtime(&now);
+  return timeinfo->tm_year > 70;
+}
+
+void start_sntp() {
+  cyw43_arch_lwip_begin();
+  if (sntp_enabled()) {
+    sntp_stop();
+  }
+  sntp_setoperatingmode(SNTP_OPMODE_POLL);
+#if SNTP_SERVER_DNS
+  sntp_setservername(0, "de.pool.ntp.org");
+#endif
+  sntp_init();
+  cyw43_arch_lwip_end();
+}
+
 int main() {
+  uint32_t last_publish{};
+  uint32_t last_sntp_retry_ms{};
   int mqtt_ret{-1};
   int wifi_status{1};
   int bme_status{-1};
+  char payload[256];
+  mqtt_client_t *client{};
   bme280_handle_t handle{};
   stdio_init_all();
+  setenv("TZ", "CET-1CEST,M3.5.0,M10.5.0", 1);
+  tzset();
   sleep_ms(3000);
   cyw43_arch_init();
   httpd_init();
@@ -125,30 +219,49 @@ int main() {
   }
   printf("Connected to wifi!\n");
   printf("IP: %s\n", ip4addr_ntoa(netif_ip4_addr(netif_default)));
+  start_sntp();
+  last_sntp_retry_ms = to_ms_since_boot(get_absolute_time());
 
   while (true) {
     while (saved_mqtt_address[0] == '\0') {
       cyw43_arch_poll();
       sleep_ms(200);
     }
-    mqtt_ret = connect_to_mqtt();
+    client = connect_to_mqtt();
-    if (!mqtt_ret) {
+    if (client == nullptr) {
-      printf("Connected to mqtt!\n");
-      break;
-    } else {
       printf("Mqtt Status: %d\n", mqtt_ret);
       reset_mqtt_config();
+    } else {
+      printf("Connected to mqtt!\n");
+      break;
     }
   }
   bme_status =
       bme280_init(&handle, 0x76, convert_Interval(saved_measure_frequency));
   if (!bme_status) {
+    last_publish = to_ms_since_boot(get_absolute_time());
     while (true) {
-      bme280_read_data(handle);
+      if ((to_ms_since_boot(get_absolute_time()) - last_publish) >=
-      printf("Messwerte: %s\n", bme280_get_json(handle));
+          saved_post_frequency * 1000) {
-      // publish_mqtt();
+        if (is_time_synced()) {
+          build_sensor_payload(payload, sizeof(payload), handle, "BME280");
+          publish_mqtt(client, payload);
+          printf("Payload: %s\n", payload);
+          last_publish = to_ms_since_boot(get_absolute_time());
+        } else {
+          printf("Waiting for SNTP sync (Current year: 1970)...\n");
+          uint32_t now_ms = to_ms_since_boot(get_absolute_time());
+          if (now_ms - last_sntp_retry_ms > 30000) {
+            printf("Retrying SNTP...\n");
+            start_sntp();
+            last_sntp_retry_ms = now_ms;
+          }
+          last_publish = to_ms_since_boot(get_absolute_time()) -
+                         (saved_post_frequency * 1000) + 5000;
+        }
+      }
       cyw43_arch_poll();
-      sleep_ms(500);
+      sleep_ms(100);
     }
   }
 }

src/time_sync.c

@@ -0,0 +1,10 @@
+#include <stdint.h>
+#include <sys/time.h>
+#include <time.h>
+
+void sntp_set_system_time_us(uint32_t sec, uint32_t us) {
+  struct timeval tv;
+  tv.tv_sec = (time_t)sec;
+  tv.tv_usec = (suseconds_t)us;
+  settimeofday(&tv, NULL);
+}