ballon_sonde.ino

#include <Wire.h>
#include <Adafruit_BME680.h>
#include <Adafruit_SGP30.h>
#include <SPI.h>
#include <SD.h>

const int chipSelect = 10;
const int uvPin = A2;
const float coeffUV = 5.0 / 1023.0;
const unsigned long interval = 15000;
unsigned long previousMillis = 0;

Adafruit_BME680 bme;
Adafruit_SGP30 sgp;

void setup() {
  Serial.begin(9600);
  delay(2000);

  if (!bme.begin(0x76)) {
    Serial.println(F("Erreur : BME680 non détecté !"));
    while (1);
  }

  bme.setTemperatureOversampling(BME680_OS_8X);
  bme.setHumidityOversampling(BME680_OS_2X);
  bme.setPressureOversampling(BME680_OS_4X);
  bme.setIIRFilterSize(BME680_FILTER_SIZE_3);
  bme.setGasHeater(320, 150);
  delay(200);

  if (!sgp.begin()) {
    Serial.println(F("Erreur : SGP30 non détecté !"));
    while (1);
  }

  if (!SD.begin(chipSelect)) {
    Serial.println(F("Erreur : carte SD non détectée !"));
    while (1);
  }

  File dataFile = SD.open("donnees.txt", FILE_WRITE);
  if (dataFile && dataFile.size() == 0) {
    dataFile.println(F("temps,temperature,pression,humidite,UV,eCO2"));
    dataFile.close();
  }

  Serial.println(F("Initialisation OK."));
}

void loop() {
  if (millis() - previousMillis < interval) return;
  previousMillis = millis();

  int uv = analogRead(uvPin);
  float uvVolt = uv * coeffUV;

  if (!bme.performReading()) {
    Serial.println(F("Erreur lecture BME680"));
    return;
  }

  if (!sgp.IAQmeasure()) {
    Serial.println(F("Erreur lecture SGP30"));
    return;
  }

  // Impression directe sans String ni buffer char[]
  File dataFile = SD.open("donnees.txt", FILE_WRITE);
  if (dataFile) {
    unsigned long now = millis();

    Serial.print(now); Serial.print(',');
    Serial.print(bme.temperature, 1); Serial.print(',');
    Serial.print(bme.pressure / 100.0, 1); Serial.print(',');
    Serial.print(bme.humidity, 1); Serial.print(',');
    // Serial.print(bme.gas_resistance / 1000.0, 1); Serial.print(',');
    Serial.print(uv); Serial.print(',');
    // Serial.print(uvVolt, 2); Serial.print(',');
    Serial.println(sgp.eCO2);
    // Serial.println(sgp.TVOC);

    dataFile.print(now); dataFile.print(',');
    dataFile.print(bme.temperature, 1); dataFile.print(',');
    dataFile.print(bme.pressure / 100.0, 1); dataFile.print(',');
    dataFile.print(bme.humidity, 1); dataFile.print(',');
    // dataFile.print(bme.gas_resistance / 1000.0, 1); dataFile.print(',');
    dataFile.print(uv); dataFile.print(',');
    // dataFile.print(uvVolt, 2); dataFile.print(',');
    dataFile.print(sgp.eCO2); dataFile.print(',');
    // dataFile.println(sgp.TVOC);

    dataFile.close();
  } else {
    Serial.println(F("Erreur écriture fichier SD !"));
  }
}