commit 47a68826dcea1a5cb08f48228fc66be06bea2581
Author: Biosias <jakub@gdos.sk>
Date:   Wed Jul 29 12:46:54 2026 +0200

    Initial commit

diff --git a/README.md b/README.md
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+# Rocket Telemetry Module
+
+Code for rocket telemetry module used on Astronomická Expedice
diff --git a/main.ino b/main.ino
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+++ b/main.ino
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+/*
+  Seeeduino XIAO ESP32-S3 + BMP280 -> WiFi -> UDP sender
+  --------------------------------------------------------
+  Reads temperature (°C) and pressure (hPa) from a BMP280 over I2C,
+  along with the WiFi signal strength (RSSI), and sends them as a
+  semicolon-delimited string (terminated with a newline) over UDP
+  to a specified IP address and port 9999.
+  Payload format: temperature;pressure;rssi\n
+  Example:        24.53;1013.25;-58
+
+  Wiring (I2C):
+    XIAO ESP32-S3 SDA (D4/GPIO5)  -> BMP280 SDA
+    XIAO ESP32-S3 SCL (D5/GPIO6)  -> BMP280 SCL
+    3V3                           -> VCC
+    GND                           -> GND
+
+  Required libraries (install via Library Manager):
+    - Adafruit BMP280 Library
+    - Adafruit Unified Sensor
+*/
+
+#include <Wire.h>
+#include <WiFi.h>
+#include <WiFiUdp.h>
+#include <Adafruit_Sensor.h>
+#include <Adafruit_BMP280.h>
+
+// ---------------- USER CONFIG ----------------
+const char* WIFI_SSID     = "control-tower-24";
+const char* WIFI_PASSWORD = "expaexpa";
+
+// Destination for UDP packets
+const char* UDP_TARGET_IP = "192.168.1.17";  // <-- change to your receiver's IP
+const uint16_t UDP_TARGET_PORT = 9999;
+
+// How often to read + send (ms)
+const unsigned long SEND_INTERVAL_MS = 500;
+
+// I2C pins for XIAO ESP32-S3 (default Wire pins)
+const int I2C_SDA_PIN = 5;  // D4
+const int I2C_SCL_PIN = 6;  // D5
+
+// BMP280 I2C address: 0x76 (SDO to GND) or 0x77 (SDO to VCC)
+const uint8_t BMP280_I2C_ADDRESS = 0x76;
+// -----------------------------------------------
+
+Adafruit_BMP280 bmp;
+WiFiUDP udp;
+
+unsigned long lastSendTime = 0;
+
+void connectWiFi() {
+  Serial.print("Connecting to WiFi");
+  WiFi.mode(WIFI_STA);
+  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
+
+  while (WiFi.status() != WL_CONNECTED) {
+    delay(400);
+    Serial.print(".");
+  }
+
+  Serial.println();
+  Serial.print("WiFi connected. IP address: ");
+  Serial.println(WiFi.localIP());
+}
+
+void setup() {
+  Serial.begin(115200);
+  delay(1000); // give the serial monitor time to attach
+
+  // Init I2C on XIAO ESP32-S3 pins
+  Wire.begin(I2C_SDA_PIN, I2C_SCL_PIN);
+
+  // Init BMP280
+  if (!bmp.begin(BMP280_I2C_ADDRESS)) {
+    Serial.println("Could not find a valid BMP280 sensor, check wiring or address!");
+    while (1) {
+      delay(1000);
+    }
+  }
+
+  // Recommended settings for weather monitoring (see Adafruit example)
+  bmp.setSampling(Adafruit_BMP280::MODE_NORMAL,
+                  Adafruit_BMP280::SAMPLING_X2,   // temperature
+                  Adafruit_BMP280::SAMPLING_X16,  // pressure
+                  Adafruit_BMP280::FILTER_X16,
+                  Adafruit_BMP280::STANDBY_MS_500);
+
+  connectWiFi();
+}
+
+  long counter = 0;
+
+void loop() {
+  // Reconnect WiFi if dropped
+  if (WiFi.status() != WL_CONNECTED) {
+    connectWiFi();
+  }
+
+  unsigned long now = millis();
+  if (now - lastSendTime >= SEND_INTERVAL_MS) {
+    lastSendTime = now;
+
+    float temperature = bmp.readTemperature();      // °C
+    float pressure     = bmp.readPressure() / 100.0F; // Pa -> hPa
+    long  rssi         = WiFi.RSSI();                 // dBm
+
+    // Build payload: counter;temperature;pressure;rssi\n
+    char payload[64];
+    snprintf(payload, sizeof(payload), "%ld;%.2f;%.2f;%ld\n", counter, temperature, pressure, rssi);
+
+    counter = counter + 1;
+
+    Serial.print("Sending UDP packet: ");
+    Serial.println(payload);
+
+    udp.beginPacket(UDP_TARGET_IP, UDP_TARGET_PORT);
+    udp.print(payload);
+    udp.endPacket();
+  }
+}