Wetterstation

Das ist ein Projekt mit einem ESP32 V4. Mit einem C++ Programm werden die Sensordaten Temperatur, Luftfeuchte und Luftdruck von einem BME280 eingelesen und an einem OLED Display angezeigt. Beide Komponenten sind am I2C-Bus angeschlossen. Das Display taktet im 15 Sekunden Rytmus die Seiten Datum/Uhrzeit, Temperatur, Luftfeuchte, Sonnenwerte und Luftdruck durch. Die Seiten können auch mit einem Taster durchgeblättert werden.

Hardware

Die Hardware für dieses Projekt:

• 1 x ESP32 V4.
• 1 x BME280.
• 1 x OLED 0,96".
• 1 x LDR Widerstand.
• 1 x Taster.
• 2x 10k Ohm Widerstand.
• Optional: 1 x WS2812B addressable RGB LED Strip.

Software

Die Software für dieses Projekt.

• C++ Programm.
• Div. Librarys.

Installation

Die Programme in die Arduino IDE kopieren und speichern.

• Die eigenen WLAN-Login-Daten eingeben.
• Die Librarys installieren.
• Die Software kompilieren und in den ESP32 laden.
• BME280 am GPIO 21 (SDA), GPIO 22 (SCL) anschliesen.
• OLED Display am GPIO 21 (SDA), GPIO 22 (SCL) anschliesen.
• LDR am GPIO 21 (SDA), GPIO 22 (SCL) anschliesen.
• RGB LEDs am GPIO 21 (SDA), GPIO 22 (SCL) anschliesen.
• Taster am GPIO 18 anschliesen.

Programm

C++ Programm

/*********
  Board: DOIT ESP32 DEVKIT V1  / V4

Einstellungen:
https://arduino.esp8266.com/stable/package_esp8266com_index.json
https://dl.espressif.com/dl/package_esp32_index.json
http://dan.drown.org/stm32duino/package_STM32duino_index.json
https://dl.espressif.com/dl/package_esp32_index.json


BME280 temperature, humidity and pressure sensor;
LDR (light dependent resistor – luminosity sensor);
0.96 inch I2C OLED Display;
Pushbutton;
12 WS2812B addressable RGB LEDs;


Component  ESP32 Pin Assignment
BME280  GPIO 21 (SDA), GPIO 22 (SCL)
OLED Display  GPIO 21 (SDA), GPIO 22 (SCL)
Light Dependent Resistor (LDR)  GPIO 33
Pushbutton  GPIO 18
Addressable RGB LEDs  GPIO 27

*/

#include <Arduino.h>
#include <Adafruit_NeoPixel.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BME280.h>
#include <WiFi.h>
#include <time.h>

// Insert your network credentials
const char* ssid     = "xxx";
const char* password = "xxx";

// NTP Server Details
const char* ntpServer = "pool.ntp.org";
const long  gmtOffset_sec = 0;
const int   daylightOffset_sec = 3600;

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

#define I2Cdisplay_SDA 21
#define I2Cdisplay_SCL 22
TwoWire I2Cdisplay = TwoWire(1);

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &I2Cdisplay, -1);

// WS2812B Addressable RGB LEDs
#define LED_PIN    27  // GPIO the LEDs are connected to
#define LED_COUNT  12  // Number of LEDs
Adafruit_NeoPixel strip(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800);

// BME280
#define I2C_SDA 21
#define I2C_SCL 22
TwoWire I2CBME = TwoWire(0);
Adafruit_BME280 bme;

// LDR (Light Dependent Resistor)
#define ldr  33

// Pushbutton
#define buttonPin  18

int buttonState;              // current reading from the input pin
int lastButtonState = LOW;    // previous reading from the input pin

unsigned long lastDebounceTime = 0;  // the last time the output pin was toggled
unsigned long debounceDelay = 50;    // the debounce time; increase if the output flickers

// Screens
int displayScreenNum = 0;
int displayScreenNumMax = 4;

unsigned long lastTimer = 0;
unsigned long timerDelay = 15000;

unsigned char temperature_icon[] ={
  0b00000001, 0b11000000, //        ###
  0b00000011, 0b11100000, //       #####
  0b00000111, 0b00100000, //      ###  #
  0b00000111, 0b11100000, //      ######
  0b00000111, 0b00100000, //      ###  #
  0b00000111, 0b11100000, //      ######
  0b00000111, 0b00100000, //      ###  #
  0b00000111, 0b11100000, //      ######
  0b00000111, 0b00100000, //      ###  #
  0b00001111, 0b11110000, //     ########
  0b00011111, 0b11111000, //    ##########
  0b00011111, 0b11111000, //    ##########
  0b00011111, 0b11111000, //    ##########
  0b00011111, 0b11111000, //    ##########
  0b00001111, 0b11110000, //     ########
  0b00000111, 0b11100000, //      ######
};

unsigned char humidity_icon[] ={
  0b00000000, 0b00000000, //
  0b00000001, 0b10000000, //        ##
  0b00000011, 0b11000000, //       ####
  0b00000111, 0b11100000, //      ######
  0b00001111, 0b11110000, //     ########
  0b00001111, 0b11110000, //     ########
  0b00011111, 0b11111000, //    ##########
  0b00011111, 0b11011000, //    ####### ##
  0b00111111, 0b10011100, //   #######  ###
  0b00111111, 0b10011100, //   #######  ###
  0b00111111, 0b00011100, //   ######   ###
  0b00011110, 0b00111000, //    ####   ###
  0b00011111, 0b11111000, //    ##########
  0b00001111, 0b11110000, //     ########
  0b00000011, 0b11000000, //       ####
  0b00000000, 0b00000000, //
};

unsigned char arrow_down_icon[] ={
  0b00001111, 0b11110000, //     ########
  0b00011111, 0b11111000, //    ##########
  0b00011111, 0b11111000, //    ##########
  0b00011100, 0b00111000, //    ###    ###
  0b00011100, 0b00111000, //    ###    ###
  0b00011100, 0b00111000, //    ###    ###
  0b01111100, 0b00111110, //  #####    #####
  0b11111100, 0b00111111, // ######    ######
  0b11111100, 0b00111111, // ######    ######
  0b01111000, 0b00011110, //  ####      ####
  0b00111100, 0b00111100, //   ####    ####
  0b00011110, 0b01111000, //    ####  ####
  0b00001111, 0b11110000, //     ########
  0b00000111, 0b11100000, //      ######
  0b00000011, 0b11000000, //       ####
  0b00000001, 0b10000000, //        ##
};

unsigned char sun_icon[] ={
  0b00000000, 0b00000000, //
  0b00100000, 0b10000010, //   #     #     #
  0b00010000, 0b10000100, //    #    #    #
  0b00001000, 0b00001000, //     #       #
  0b00000001, 0b11000000, //        ###
  0b00000111, 0b11110000, //      #######
  0b00000111, 0b11110000, //      #######
  0b00001111, 0b11111000, //     #########
  0b01101111, 0b11111011, //  ## ######### ##
  0b00001111, 0b11111000, //     #########
  0b00000111, 0b11110000, //      #######
  0b00000111, 0b11110000, //      #######
  0b00010001, 0b11000100, //    #   ###   #
  0b00100000, 0b00000010, //   #           #
  0b01000000, 0b10000001, //  #      #      #
  0b00000000, 0b10000000, //         #
};

// Clear the LEDs
void colorWipe(uint32_t color, int wait, int numNeoPixels) {
  for(int i=0; i<numNeoPixels; i++) { // For each pixel in strip...
    strip.setPixelColor(i, color);         //  Set pixel's color (in RAM)
    strip.show();                          //  Update strip to match
    delay(wait);                           //  Pause for a moment
  }
}

// Rainbow cycle along all LEDs. Pass delay time (in ms) between frames.
void rainbow(int wait) {
  long firstPixelHue = 256;
    for(int i=0; i<strip.numPixels(); i++) { // For each pixel in strip...
      int pixelHue = firstPixelHue + (i * 65536L / strip.numPixels());
      strip.setPixelColor(i, strip.gamma32(strip.ColorHSV(pixelHue)));
    }
    strip.show(); // Update strip with new contents
    delay(wait);  // Pause for a moment
}

// Create display marker for each screen
void displayIndicator(int displayNumber) {
  int xCoordinates[5] = {44, 54, 64, 74, 84};
  for (int i =0; i<5; i++) {
    if (i == displayNumber) {
      display.fillCircle(xCoordinates[i], 60, 2, WHITE);
    }
    else {
      display.drawCircle(xCoordinates[i], 60, 2, WHITE);
    }
  }
}

//SCREEN NUMBER 0: DATE AND TIME
void displayLocalTime(){
  struct tm timeinfo;
  if(!getLocalTime(&timeinfo)){
    Serial.println("Failed to obtain time");
  }
  Serial.println(&timeinfo, "%A, %B %d %Y %H:%M:%S");

  //GET DATE
  //Get full weekday name
  char weekDay[10];
  strftime(weekDay, sizeof(weekDay), "%a", &timeinfo);
  //Get day of month
  char dayMonth[4];
  strftime(dayMonth, sizeof(dayMonth), "%d", &timeinfo);
  //Get abbreviated month name
  char monthName[5];
  strftime(monthName, sizeof(monthName), "%b", &timeinfo);
  //Get year
  char year[6];
  strftime(year, sizeof(year), "%Y", &timeinfo);

  //GET TIME
  //Get hour (12 hour format)
  /*char hour[4];
  strftime(hour, sizeof(hour), "%I", &timeinfo);*/

  //Get hour (24 hour format)
  char hour[4];
  strftime(hour, sizeof(hour), "%H", &timeinfo);
  //Get minute
  char minute[4];
  strftime(minute, sizeof(minute), "%M", &timeinfo);

  //Display Date and Time on OLED display
  display.clearDisplay();
  display.setTextColor(WHITE);
  display.setTextSize(3);
  display.setCursor(19,5);
  display.print(hour);
  display.print(":");
  display.print(minute);
  display.setTextSize(1);
  display.setCursor(16,40);
  display.print(weekDay);
  display.print(", ");
  display.print(dayMonth);
  display.print(" ");
  display.print(monthName);
  display.print(" ");
  display.print(year);
  displayIndicator(displayScreenNum);
  display.display();
  rainbow(10);
}

// SCREEN NUMBER 1: TEMPERATURE
void displayTemperature(){
  display.clearDisplay();
  display.setTextSize(2);
  display.drawBitmap(15, 5, temperature_icon, 16, 16 ,1);
  display.setCursor(35, 5);
  float temperature = bme.readTemperature();
  display.print(temperature);
  display.cp437(true);
  display.setTextSize(1);
  display.print(" ");
  display.write(167);
  display.print("C");
  display.setCursor(0, 34);
  display.setTextSize(1);
  display.print("Humidity: ");
  display.print(bme.readHumidity());
  display.print(" %");
  display.setCursor(0, 44);
  display.setTextSize(1);
  display.print("Pressure: ");
  display.print(bme.readPressure()/100.0F);
  display.print(" hpa");
  displayIndicator(displayScreenNum);
  display.display();
  int temperaturePer = map(temperature, -5, 36, 0, LED_COUNT-1);
  colorWipe(strip.Color(0,   255,   0), 50, temperaturePer);
}

// SCREEN NUMBER 2: HUMIDITY
void displayHumidity(){
  display.clearDisplay();
  display.setTextSize(2);
  display.drawBitmap(15, 5, humidity_icon, 16, 16 ,1);
  display.setCursor(35, 5);
  float humidity = bme.readHumidity();
  display.print(humidity);
  display.print(" %");
  display.setCursor(0, 34);
  display.setTextSize(1);
  display.print("Temperature: ");
  display.print(bme.readTemperature());
  display.cp437(true);
  display.print(" ");
  display.write(167);
  display.print("C");
  display.setCursor(0, 44);
  display.setTextSize(1);
  display.print("Pressure: ");
  display.print(bme.readPressure()/100.0F);
  display.print(" hpa");
  displayIndicator(displayScreenNum);
  display.display();
  int humidityPer = map(humidity, 0, 100, 0, LED_COUNT-1);
  colorWipe(strip.Color(0,   0,   255), 50, humidityPer);
}

// SCREEN NUMBER 3: PRESSURE
void displayPressure(){
  display.clearDisplay();
  display.setTextSize(2);
  display.drawBitmap(0, 5, arrow_down_icon, 16, 16 ,1);
  display.setCursor(20, 5);
  display.print(bme.readPressure()/100.0F);
  display.setTextSize(1);
  display.print(" hpa");
  display.setCursor(0, 34);
  display.setTextSize(1);
  display.print("Temperature: ");
  display.print(bme.readTemperature());
  display.cp437(true);
  display.print(" ");
  display.write(167);
  display.print("C");
  display.setCursor(0, 44);
  display.setTextSize(1);
  display.print("Humidity: ");
  display.print(bme.readHumidity());
  display.print(" hpa");
  displayIndicator(displayScreenNum);
  display.display();
  colorWipe(strip.Color(255,   0,   255), 50, 12);
}

// SCREEN NUMBER 4: LUMINOSITY
void displayLDR(){
  display.clearDisplay();
  display.setTextSize(2);
  display.drawBitmap(33, 5, sun_icon, 16, 16 ,1);
  display.setCursor(53, 5);
  int ldrReading = map(analogRead(ldr), 0, 4095, 100, 0);
  display.print(ldrReading);
  display.print(" %");
  display.setTextSize(1);
  display.setCursor(0, 34);
  display.print("Temperature: ");
  display.print(bme.readTemperature());
  display.print(" ");
  display.cp437(true);
  display.write(167);
  display.print("C");
  display.setCursor(0, 44);
  display.setTextSize(1);
  display.print("Humidity: ");
  display.print(bme.readHumidity());
  display.print(" %");
  display.setCursor(0, 44);
  displayIndicator(displayScreenNum);
  display.display();
  int ldrReadingPer = map(ldrReading, 0, 100, 0, LED_COUNT-1);
  colorWipe(strip.Color(255,   255,   0), 50, ldrReadingPer);
}

// Display the right screen accordingly to the displayScreenNum
void updateScreen() {
  colorWipe(strip.Color(0, 0, 0), 1, LED_COUNT);
  if (displayScreenNum == 0){
    displayLocalTime();
  }
  else if (displayScreenNum == 1) {
    displayTemperature();
  }
  else if (displayScreenNum ==2){
    displayHumidity();
  }
  else if (displayScreenNum==3){
    displayPressure();
  }
  else {
    displayLDR();
  }
}

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

  // Initialize the pushbutton pin as an input
  pinMode(buttonPin, INPUT);

  I2CBME.begin(I2C_SDA, I2C_SCL, 100000);
  I2Cdisplay.begin(I2Cdisplay_SDA, I2Cdisplay_SCL, 100000);

  // Initialize OLED Display
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.clearDisplay();
  display.setTextColor(WHITE);

  // Initialize BME280
  bool status = bme.begin(0x76, &I2CBME);
  if (!status) {
    Serial.println("Could not find a valid BME280 sensor, check wiring!");
    while (1);
  }

  // Initialize WS2812B LEDs
  strip.begin();           // INITIALIZE NeoPixel strip object (REQUIRED)
  strip.show();            // Turn OFF all pixels ASAP
  strip.setBrightness(50); // Set BRIGHTNESS to about 1/5 (max = 255)

  // Connect to Wi-Fi
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected.");

  // Init and get the time
  configTime(gmtOffset_sec, daylightOffset_sec, ntpServer);
}

void loop() {
  // read the state of the switch into a local variable
  int reading = digitalRead(buttonPin);

  // Change screen when the pushbutton is pressed
  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }

  if ((millis() - lastDebounceTime) > debounceDelay) {
    if (reading != buttonState) {
      buttonState = reading;
      if (buttonState == HIGH) {
        updateScreen();
        Serial.println(displayScreenNum);
        if(displayScreenNum < displayScreenNumMax) {
          displayScreenNum++;
        }
        else {
          displayScreenNum = 0;
        }
        lastTimer = millis();
      }
    }
  }
  lastButtonState = reading;

  // Change screen every 15 seconds (timerDelay variable)
  if ((millis() - lastTimer) > timerDelay) {
    updateScreen();
    Serial.println(displayScreenNum);
    if(displayScreenNum < displayScreenNumMax) {
      displayScreenNum++;
    }
    else {
      displayScreenNum = 0;
    }
    lastTimer = millis();
  }
}

RAW code

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