Esp32, ssd1306, weather data display (No.4 )

Nowadays, the weather forecast became more accurate. You can search in the internet and get information. It is very nice.

However, I thought it might be nicer if I have a display which tells the weather data. 

I used website called open weather map. This is a little bit complicated project because involving request data, receive data and extract data. 

The theory 

So, the theory is esp32 request data to open weather map. Then open weather map send the data as Jason format. So, we extract the data we want from that format. Then we display the data to the organic LED display. 

Necessary equipment

1. ESP32 ( WiFi module ) 

2. SSD1306 (Organic LED display ) 

Connection 

ESP32 <---> SSD1306 

3.3V <---> Vin

GND <---> GND

D22 <---> SCL 

D21 <---> SDA

Code

#include <WiFiClient.h>

#include <HTTPClient.h>

#include <ArduinoJson.h>

#include<Wire.h>             //

#include<Adafruit_GFX.h>     //ダウンロードしたライブラリをインクルード

#include<Adafruit_SSD1306.h>

#include <TimeLib.h>

//NTP関連

struct tm timeInfo;

int now_hour;

#define SCREEN_WIDTH 128 // OLED display width,  in pixels

#define SCREEN_HEIGHT 64 // OLED display height, in pixels

Adafruit_SSD1306 display(128, 64, &Wire, -1);

const char* ssid = "";/your wifi ssid

const char* password =  "";/pw

const String endpoint = "";

const String key = "";

const String endpointone = "";

void setup() {

  Serial.begin(115200);

  display.begin();

  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3c)) {

    Serial.println(F("SSD1306 allocation failed"));

    for (;;); // Don't proceed, loop forever

  }

  display.clearDisplay();

  display.setTextSize(1);

  display.setTextColor(SSD1306_WHITE);

  int cursorPosition = 0;

  display.setCursor(0, 0);

  display.print("   Connecting");

  Serial.println("Connecting");

  display.display();

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {

    delay(1000);

    Serial.println("Connecting to WiFi..");

    display.setCursor(0, 2);

    display.print(".");

    cursorPosition++;

    display.display();

  }

  display.clearDisplay();

  display.print("   Connected!");

  display.display();

  Serial.println("Connected to the WiFi network");

}

void loop() {

  if ((WiFi.status() == WL_CONNECTED)) {

    WiFiClient client;

    HTTPClient http;

    http.begin(client, endpoint + key); //URLを指定

    int httpCode = http.GET();  //GETリクエストを送信

    if (httpCode > 0) { //返答がある場合

      String payload = http.getString();  //返答（JSON形式）を取得

      Serial.println(httpCode);

      Serial.println(payload);

      const size_t capacity = JSON_ARRAY_SIZE(1) + JSON_OBJECT_SIZE(1) + JSON_OBJECT_SIZE(2) + JSON_OBJECT_SIZE(3) + JSON_OBJECT_SIZE(4) + JSON_OBJECT_SIZE(5) + JSON_OBJECT_SIZE(8) + JSON_OBJECT_SIZE(13) + 470;

      DynamicJsonBuffer jsonBuffer(capacity);

      String json = payload;

      //jsonオブジェクトの作成

      JsonObject& weatherdata = jsonBuffer.parseObject(json);

      //パースが成功したかどうかを確認

      if (!weatherdata.success()) {

        Serial.println("parseObject() failed");

      }

      //各データを抜き出し

      const char* weather = weatherdata["weather"][0]["description"];

      const double temp = weatherdata["main"]["temp"];

      int humidity = weatherdata["main"]["humidity"];

      //LCDに表示

      display.clearDisplay();//画面を消去

      //天気を表示

      display.setCursor(0, 0);

      display.println("Current weather");

      display.println(weather);

      //気温を表示

      String temp_str = String(temp - 273.15);

      display.print(temp_str);

      display.print((char)247);

      display.println("C");

      Serial.println(weather);

      Serial.println(temp_str);

      display.print(humidity);

      display.print("%");

      display.display();

      delay(3000);

    }

    else {

      Serial.println("Error on HTTP request");

    }

  }

  if ((WiFi.status() == WL_CONNECTED)) {

    WiFiClient client;

    HTTPClient http;

    http.begin(client, endpointone + key); //URLを指定

    int httpCodeone = http.GET();  //GETリクエストを送信

    if (httpCodeone > 0) { //返答がある場合

      String payloadone = http.getString();  //返答（JSON形式）を取得

      Serial.println(httpCodeone);

      Serial.println(payloadone);

      const size_t capacity = 40 * JSON_ARRAY_SIZE(1) + JSON_ARRAY_SIZE(40) + 86 * JSON_OBJECT_SIZE(1) + JSON_OBJECT_SIZE(2) + 40 * JSON_OBJECT_SIZE(3) + 40 * JSON_OBJECT_SIZE(4) + JSON_OBJECT_SIZE(5) + JSON_OBJECT_SIZE(8) + 74 * JSON_OBJECT_SIZE(9) + 6 * JSON_OBJECT_SIZE(10) + 14380;

      DynamicJsonBuffer jsonBuffer(capacity);

      String json = payloadone;

      JsonObject& root = jsonBuffer.parseObject(json);

      int data_number = now_hour / 3 + 4;

      if (!root.success()) {

        Serial.println("parseObject() failed");

      }

      if (root.success()) {

        const char* weatherf = root["list"][data_number]["weather"][0]["description"];

        const double tempf = root["list"][data_number]["main"]["temp"];

        display.clearDisplay();

        display.setCursor(0, 0);

        display.println("Forecast 12h later");

        display.println(weatherf);

        

        String temp_f = String(tempf - 273.15);

        display.print(temp_f);

        display.print((char)247);

        display.print("C");

        display.display();

        delay(3000);

      }

      http.end(); //Free the resources

    }

    delay(5000);

  }

}