dht lora sender demo

Author: Richard3366

examples/Sensor/DHT11_LoRa_sender/DHT11_LoRa_sender.ino

@@ -0,0 +1,85 @@
+#include <DHTesp.h>
+#include "LoRaWan_APP.h"
+#include "Arduino.h"
+
+// DHT11 Configuration
+#define DHT_PIN 1  // GPIO1 connected to DHT11 (avoid using GPIO1)
+DHTesp dht;
+
+// LoRa Configuration
+#define RF_FREQUENCY                915000000   // Hz (adjust according to your region)
+#define TX_OUTPUT_POWER             14          // dBm (increase power to extend transmission range)
+#define LORA_BANDWIDTH              0           // 125 kHz
+#define LORA_SPREADING_FACTOR       7           // SF7
+#define LORA_CODINGRATE             1           // 4/5
+#define LORA_PREAMBLE_LENGTH        8           // Preamble length
+#define LORA_FIX_LENGTH_PAYLOAD_ON  false
+#define LORA_IQ_INVERSION_ON        false
+
+#define BUFFER_SIZE                 50          // Data buffer size
+char txpacket[BUFFER_SIZE];                    // Transmission buffer
+bool lora_idle = true;                         // LoRa idle state flag
+
+// LoRa event callbacks
+static RadioEvents_t RadioEvents;
+void OnTxDone(void);
+void OnTxTimeout(void);
+
+void setup() {
+  Serial.begin(115200);
+  
+  // Initialize DHT11
+  dht.setup(DHT_PIN, DHTesp::DHT11);
+  Serial.println("DHT11 Initialized");
+
+  // Initialize LoRa
+  Mcu.begin(HELTEC_BOARD, SLOW_CLK_TPYE); // Adjust parameters according to your board
+  RadioEvents.TxDone = OnTxDone;
+  RadioEvents.TxTimeout = OnTxTimeout;
+  
+  Radio.Init(&RadioEvents);
+  Radio.SetChannel(RF_FREQUENCY);
+  Radio.SetTxConfig(MODEM_LORA, TX_OUTPUT_POWER, 0, LORA_BANDWIDTH,
+                   LORA_SPREADING_FACTOR, LORA_CODINGRATE,
+                   LORA_PREAMBLE_LENGTH, LORA_FIX_LENGTH_PAYLOAD_ON,
+                   true, 0, 0, LORA_IQ_INVERSION_ON, 3000);
+}
+
+void loop() {
+  if (lora_idle) {
+    delay(2000); // DHT11 requires at least 1-second sampling interval
+
+    // Read temperature and humidity data
+    TempAndHumidity data = dht.getTempAndHumidity();
+    if (dht.getStatus() != DHTesp::ERROR_NONE) {
+      Serial.println("DHT11 read failed: " + String(dht.getStatusString()));
+      return;
+    }
+
+    // Format data as JSON string (example: {"t":25.5,"h":50.0})
+    snprintf(txpacket, BUFFER_SIZE, 
+             "{\"t\":%.1f,\"h\":%.1f}", 
+             data.temperature, 
+             data.humidity);
+
+    Serial.printf("Sending data: %s\n", txpacket);
+
+    // Transmit data via LoRa
+    Radio.Send((uint8_t *)txpacket, strlen(txpacket));
+    lora_idle = false;
+  }
+  Radio.IrqProcess(); // Process LoRa events
+}
+
+// LoRa transmission complete callback
+void OnTxDone(void) {
+  Serial.println("LoRa transmission successful");
+  lora_idle = true;
+}
+
+// LoRa transmission timeout callback
+void OnTxTimeout(void) {
+  Radio.Sleep();
+  Serial.println("LoRa transmission timeout");
+  lora_idle = true;
+}