Functions returning variables

[iangill]

This is the whoe sketch

#include <Arduino.h>
#include <SD.h>
#include <DHT22.h>
#include <Wire.h>
#include <WiFi.h>
#include "time.h"
#include "SPI.h"
#include "FS.h"
#include <Bme280.h>
//#include <BME280I2C.h>

#define LED_Flash 25
#define I2C_SDA 33
#define I2C_SCL 32
Bme280TwoWire sensor;
//BME280I2C bme;    // Default : forced mode, standby time = 1000 ms
// Oversampling = pressure ×1, temperature ×1, humidity ×1, filter off,

DHT22 dht22(17);

unsigned long intervalCheck;
const char* ssid = "Utopia";
const char* password = "password";
const char* ntpServer = "pool.ntp.org";
const long gmtOffset_sec = 3600 * 0;
const int daylightOffset_sec = 3600 * 0;

float temperature;
float humidity;
float humid;
char fileName[18];
char readingTimestamp[30];
char readings[30];

const float Av = 5.0;  //number of readings for average
const int Av1 = int(Av);

float humidAv[Av1];
byte humCount = 0;
bool start = 1;
int refTime = 0;
File myFile;


/////////////////////////////////////////////////////////////////////
void setup() {
  delay(5000);
  pinMode(LED_Flash, OUTPUT);
  Serial.begin(115200);
  for (int x = 0; x < 10; x++) {
    Serial.println();
  }
  Serial.print("Initializing SD card...");

  if (!SD.begin()) {
    Serial.println("Card Mount Failed");
    return;
  }
  uint8_t cardType = SD.cardType();

  if (cardType == CARD_NONE) {
    Serial.println("No SD card attached");
    return;
  }

  Serial.print("SD Card Type: ");
  if (cardType == CARD_MMC) {
    Serial.println("MMC");
  } else if (cardType == CARD_SD) {
    Serial.println("SDSC");
  } else if (cardType == CARD_SDHC) {
    Serial.println("SDHC");
  } else {
    Serial.println("UNKNOWN");
  }
  WiFi.mode(WIFI_STA);  // Optional
  WiFi.begin(ssid, password);
  Serial.println("\nConnecting");

  while (WiFi.status() != WL_CONNECTED) {
    digitalWrite(LED_Flash, HIGH);
    Serial.print(".");
    delay(100);
    digitalWrite(LED_Flash, LOW);
    delay(100);
  }
  Serial.println(" Connected");

  listDir(SD, "/", 0);
  Serial.println();
  Serial.printf("Total space: %lluMB\n", SD.totalBytes() / (1024 * 1024));
  Serial.printf("Used space: %lluMB\n", SD.usedBytes() / (1024 * 1024));


  configTime(gmtOffset_sec, daylightOffset_sec, ntpServer);

  struct tm timeinfo;
  if (!getLocalTime(&timeinfo)) {
    Serial.println("Failed to obtain time");
  }





  delay(3000);


  intervalCheck = (timeinfo.tm_min * 60 + timeinfo.tm_sec);

  Wire.begin(I2C_SDA, I2C_SCL);

  /*while(!bme.begin())
  {
    Serial.println("Could not find BME280 sensor!");
    delay(1000);
  }

  switch(bme.chipModel())
  {
     case BME280::ChipModel_BME280:
       Serial.println("Found BME280 sensor! Success.");
       break;
     case BME280::ChipModel_BMP280:
       Serial.println("Found BMP280 sensor! No Humidity available.");
       break;
     default:
       Serial.println("Found UNKNOWN sensor! Error!");
  }*/

  sensor.begin(Bme280TwoWireAddress::Primary);
  sensor.setSettings(Bme280Settings::indoor());



  digitalWrite(LED_Flash, HIGH);
}


/////////////////////////////////////////////////////////////////
void loop() {
  //humid_temp();

  if (touchRead(4)<40)
  {
    digitalWrite(LED_Flash, HIGH);
    delay(10000);
    digitalWrite(LED_Flash, LOW);
  }

  float temperature = dht22.getTemperature() * 1.0;
  delay(50);
  float humidity = dht22.getHumidity() * 1.0;
  delay(50);

  struct tm timeinfo;
  if (!getLocalTime(&timeinfo)) {
    Serial.println("Failed to obtain time");
  }


  if ((timeinfo.tm_min * 60 + timeinfo.tm_sec - intervalCheck) >= (Av * 5)) {  //check for interval
    intervalCheck = (timeinfo.tm_min * 60 + timeinfo.tm_sec);
    if (humidity != humid) {  //check if humidity has changed since last reading

      if (start) {
        sprintf(fileName, "/%02d%02d%02d00.csv", timeinfo.tm_mon + 1, timeinfo.tm_mday, timeinfo.tm_hour);  // make file name from date and time
        Serial.println();
        Serial.print("File Name =  ");
        Serial.println(fileName);

        for (int i = 0; i <= Av - 1; i++) {



          /*set start humidity, all values in matrix from 1 reading
          to stop initial readings being unusually HIGH
          */


          humidAv[i] = humidity;
        }
        refTime = timeinfo.tm_mday*24+timeinfo.tm_hour;
        start = 0;
      }

      float hum = 0.0;
      humidAv[humCount] = humidity;
      for (int i = 0; i <= Av - 1; i++) {  //find mean humidity over 5 readings

        hum = hum + humidAv[i];
      }
      humid = float(hum / Av);
      hum = 0;
      humCount++;
      if (humCount > Av - 1) {
        humCount = 0;
      }

      float temperature2 = sensor.getTemperature();
      float pressure = sensor.getPressure() * 1.005;
      

      Serial.print(&timeinfo, "%A, %B %d %Y %H:%M:%S ");

      digitalWrite(LED_Flash, HIGH);

      Serial.print("   ");
      Serial.print("BME289 T = ");
      Serial.print(temperature2, 2);
      Serial.print(" ");
      Serial.print(" deg. C,   T = ");

      Serial.print("DHT22 T = ");
      Serial.print(temperature, 2);
      Serial.print(" ");
      Serial.print(" deg. C,   H = Av ");

      Serial.print(humid, 2);
      Serial.print(" actual ");
      Serial.print(humidity, 2);
      Serial.print("%    ");
      Serial.print("P = ");
      Serial.print(pressure);
      Serial.println(" Pa ");




      sprintf(readingTimestamp, "%02d/%02d/%04d %02d:%02d:%02d,", timeinfo.tm_mday, timeinfo.tm_mon + 1, timeinfo.tm_year + 1900, timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec);
      appendFile(SD, fileName, readingTimestamp);
      appendFile(SD, fileName, NumToChar(humid));
      appendFile(SD, fileName, NumToChar(temperature2));
      appendFile(SD, fileName, NumToChar(pressure));
      appendFile(SD, fileName, "\n");  //new line

      appendFile(SD, "/Ongoing.csv", readingTimestamp);
      appendFile(SD, "/Ongoing.csv", NumToChar(humid));
       appendFile(SD, "/Ongoing.csv", NumToChar(temperature2));
       appendFile(SD, "/Ongoing.csv", NumToChar(pressure));
      appendFile(SD, "/Ongoing.csv", "\n");  //new line


      humid = humidity;
    }


    if (timeinfo.tm_mday*24+timeinfo.tm_hour > refTime) {
      start = 1;

    }
  }


  digitalWrite(LED_Flash, LOW);
}

//////////////////////////////////////////////////////////////////////

char* NumToChar(float number) {
  String numberAsString = String(number, 3) + ",";
  static char numberAsChar[10];
  numberAsString.toCharArray(numberAsChar, 10);
  //Serial.print(numberAsChar);

  return numberAsChar;
}

//////////////////////////////////////////////////////////////////////


void appendFile(fs::FS& fs, const char* path, const char* message) {


  File file = fs.open(path, FILE_APPEND);
  if (!file) {
    Serial.println("Failed to open file for appending");
    return;
  }
  if (file.print(message)) {

  } else {
    Serial.println("Append failed");
  }
  file.close();
}
///////////////////////////////////////////////////////////////////
void listDir(fs::FS& fs, const char* dirname, uint8_t levels) {
  Serial.printf("Listing directory: %s\n", dirname);

  File root = fs.open(dirname);
  if (!root) {
    Serial.println("Failed to open directory");
    return;
  }
  if (!root.isDirectory()) {
    Serial.println("Not a directory");
    return;
  }

  File file = root.openNextFile();
  while (file) {
    if (file.isDirectory()) {
      Serial.print("  DIR : ");
      Serial.println(file.name());
      if (levels) {
        listDir(fs, file.path(), levels - 1);
      }
    } else {
      Serial.print("  FILE: ");
      Serial.print(file.name());
      Serial.print("  SIZE: ");
      Serial.println(file.size());
    }
    file = root.openNextFile();
  }
}
///////////////////////////////////////////////////////////