Temp

#include <Arduino.h>
#include <U8g2lib.h>

#ifdef U8X8_HAVE_HW_SPI
#include <SPI.h>
#endif
#ifdef U8X8_HAVE_HW_I2C
#include <Wire.h>
#endif

#include <SPI.h>
#include <SD.h>

File myFile;

U8G2_SSD1306_128X64_NONAME_F_SW_I2C u8g2(U8G2_R0, /* clock=/ SCL, / data=/ SDA, / reset=*/ U8X8_PIN_NONE);   // All Boards without Reset of the Display

#include <WEMOS_SHT3X.h>

SHT3X sht30(0x44);

  float temp_c;
  float temp_f;
  float humidity2;
  boolean sdini = 1;

  int val_temp;
  int val_humi;

void setup() {

  Serial.begin(115200);
  delay(100);
  pinMode(LED_BUILTIN, OUTPUT);
  Serial.println("Wemos boot");
  u8g2.begin();
  u8g2.clearBuffer();
  u8g2.setFont(u8g2_font_5x7_mr);
  u8g2.setCursor(0, 10);
  u8g2.print("WEMOS BOOTING...");
  u8g2.sendBuffer();
  u8g2.clearBuffer();
  digitalWrite(LED_BUILTIN, HIGH);

  //----------------------------------------------
  if (sdini == 1){
  Serial.print("Initializing SD card...");

  //if (!SD.begin(4)) {
  if (!SD.begin(15)) {
    Serial.println("initialization failed!");
    delay(200);
    return;
  }
  Serial.println("initialization done.");
  sdini = 0;
}
}


void loop() {
//  SPI.setDataMode(SPI_MODE3);
  delay(5000);
  digitalWrite(LED_BUILTIN, LOW);
  delay(10);
  digitalWrite(LED_BUILTIN, HIGH);

  mojafunkcia();

  u8g2.setFont(u8g2_font_inb19_mf );
  u8g2.setCursor(7, 34);
  //u8g2.print("T: ");
  u8g2.print(sht30.cTemp);
  u8g2.print((char)176);
  u8g2.print("C");
  u8g2.setCursor(7, 64);
  //u8g2.print("H: ");
  u8g2.print(sht30.humidity);
  u8g2.print(" %");
  u8g2.sendBuffer();

//-----------------------------------------------------------------------//

  delay(2000);


  myFile = SD.open("test.txt", FILE_WRITE);
  if (myFile) {
    Serial.println("Writing TEMP to test.txt...");
    myFile.print("TEMP ");
    delay(50);
    myFile.print(sht30.cTemp);
    delay(50);
    myFile.print((char)176);
    delay(50);
    myFile.print("C;");

    Serial.println("Writing HUMI to test.txt...");
    myFile.print("HUMI ");
    delay(50);
    myFile.print(sht30.humidity);
    delay(50);
    myFile.println("%;");
    delay(50);
    myFile.close();
    delay(50);

    Serial.println("done.");
    Serial.println();
  } else {
    // if the file didn't open, print an error:
    Serial.println("error opening test.txt");
  }


}



void mojafunkcia()
{

  if(sht30.get()==0){

    //sht30.get();
    Serial.print("Temperature in Celsius : ");
    Serial.println(sht30.cTemp);
    Serial.print("Relative Humidity : ");
    Serial.println(sht30.humidity);


  }
  else
  {
    Serial.println("Temperature read error!");
  }

}