iot_weather_step2.ino

/**************************************************************************
 read bme280 data and display on ssd1306 
 **************************************************************************/

#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#include <Adafruit_Sensor.h>
#include <Adafruit_BME280.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET     4 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

Adafruit_BME280 bme; // I2C

volatile byte revolutions;

// interrupt routine to count revolutions
void IRAM_ATTR isr() {
  revolutions += 1;
}

void setup() {
  Serial.begin(115200);

  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3C for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }

  unsigned status;

  // default settings
  status = bme.begin(0x76);  
  if (!status) {
        Serial.println("Could not find a valid BME280 sensor, check wiring, address, sensor ID!");
        Serial.print("SensorID was: 0x"); Serial.println(bme.sensorID(),16);
        Serial.print("        ID of 0xFF probably means a bad address, a BMP 180 or BMP 085\n");
        Serial.print("   ID of 0x56-0x58 represents a BMP 280,\n");
        Serial.print("        ID of 0x60 represents a BME 280.\n");
        Serial.print("        ID of 0x61 represents a BME 680.\n");
        while (1) delay(10);
  }

  // attach pin 14 to interrupt routine
  pinMode(14, INPUT);
  attachInterrupt(14, isr, FALLING);

}

void loop() {

  display.clearDisplay();

  display.setTextSize(1);             // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE);        // Draw white text

  display.setCursor(0,0);            
  display.print("Temperatur: ");
  display.setCursor(70,0);
  display.print(bme.readTemperature());
  display.setCursor(100,0);
  display.print(" *C");

  display.setCursor(0,10);            
  display.print("Luftdruck: ");
  display.setCursor(65,10);
  display.print(bme.readPressure() / 100.0F);
  display.setCursor(100,10);
  display.print(" hPa");

  display.setCursor(0,20);            
  display.print("Feuchtigkeit: ");
  display.setCursor(80,20);
  display.print(bme.readHumidity());
  display.setCursor(110,20);
  display.print(" %");

  display.setCursor(0,30);            
  display.print("Wind: ");
  display.setCursor(50,30);
  display.print(revolutions*6*16*0.001885); // revolutions in 60sec to km/h at 16cm diameter
  display.setCursor(80,30);
  display.print(" km/h");

  display.display();

  revolutions=0;

  // wait 10s
  delay(10000);
  
}