WebAPIから天気情報を取得して、LCDに表示する

ProjectX.ino

#include <ArduinoJson.h>
#include <LiquidCrystal.h>
#include <SPI.h>
#include <WiFi.h>

// select the pins used on the LCD panel
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

// define some values used by the panel and buttons
int lcd_key     = 0;
int adc_key_in  = 0;
#define btnRIGHT  0
#define btnUP     1
#define btnDOWN   2
#define btnLEFT   3
#define btnSELECT 4
#define btnNONE   5

#define COUNTRY 0
#define CITY 1
#define WEATHER 2

int screen_status = 0;
int selected_city = 1;

char ssid[] = "YOUR SSID"; //  your network SSID (name) 
char pass[] = "YOUR PASSWORD";    // your network password (use for WPA, or use as key for WEP)
int keyIndex = 0;            // your network key Index number (needed only for WEP)

int status = WL_IDLE_STATUS;
char server[] = "api.openweathermap.org";
char parameter[] = "/data/2.5/weather?q=Tokyo,jp";

WiFiClient client;

// read the buttons
int read_LCD_buttons()
{
  adc_key_in = analogRead(0);      // read the value from the sensor 
  // my buttons when read are centered at these valies: 0, 144, 329, 504, 741
  // we add approx 50 to those values and check to see if we are close
  if (adc_key_in > 1000) return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result
  // For V1.1 us this threshold
  if (adc_key_in < 50)   return btnRIGHT;  
  if (adc_key_in < 250)  return btnUP; 
  if (adc_key_in < 450)  return btnDOWN; 
  if (adc_key_in < 650)  return btnLEFT; 
  if (adc_key_in < 850)  return btnSELECT;  

  return btnNONE;  // when all others fail, return this...
}

void clearTop() {
  lcd.setCursor(0,0);
  lcd.print("                ");
}
void clearBottom() {
  lcd.setCursor(0,1);
  lcd.print("                ");
}
void writeLcdTop(char* str) {
  clearTop();
  lcd.setCursor(0,0);
  lcd.print(str);
}
void writeLcdTop(const char* str) {
  clearTop();
  lcd.setCursor(0,0);
  lcd.print(str);
}
void writeLcdTop(String str) {
  clearTop();
  lcd.setCursor(0,0);
  lcd.print(str);
}
void writeLcdBtm(char* str) {
  clearBottom();
  lcd.setCursor(0,1);
  lcd.print(str);
}
void writeLcdBtm(const char* str) {
  clearBottom();
  lcd.setCursor(0,1);
  lcd.print(str);
}
void writeLcdBtm(String str) {
  clearBottom();
  lcd.setCursor(0,1);
  lcd.print(str);
}
String getCity() {
  switch (selected_city) {
  case 0:
    {
      return "Sapporo,jp";
      break;
    }
  case 1:
    {
      return "Tokyo,jp";
      break;
    }
  case 2:
    {
      return "Osaka,jp";
      break;
    }
  case 3:
    {
      return "Fukuoka,jp";
      break;
    }
  case 4:
    {
      return "NY,us";
      break;
    }
  case 5:
    {
      return "Paris,fr";
      break;
    }
  }
}

void getWeather() {
  writeLcdTop(getCity());
  writeLcdBtm("--Preparing WiFi");

  while (status != WL_CONNECTED) {
    // Connect to WPA/WPA2 network. Change this line if using open or WEP network:    
    status = WiFi.begin(ssid, pass);

    delay(300);
  }
  writeLcdBtm("--Connecting");
  client.stop();

  if (client.connect(server, 80)) {

    client.println("GET /data/2.5/weather?q=" + getCity() + " HTTP/1.1");

    client.println("Host: api.openweathermap.org");
    client.println("Connection: close");
    client.println();

    // read weather
    char tmp;
    int cnt = 0;
    int braceCnt = 0;
    char json[511];
    while (client.available() && cnt < 1000) {
      tmp = client.read();
      if (tmp == '{') {
        braceCnt++;
      }

      if (braceCnt > 0) {
        json[cnt] = tmp;
        cnt++;
      }
      if (tmp == '}') {
        braceCnt--;
      }
    }
    json[cnt] = '\0';
    Serial.println();
    Serial.println("read");
    StaticJsonBuffer<1000> jsonBuffer;
    JsonObject& root = jsonBuffer.parseObject(json);
    if (!root.success())
    {
      Serial.println("parseObject() failed");
      return;
    }
    // set weather
    const char* wmain = root["weather"][0]["main"];
    const char* wdesc = root["weather"][0]["description"];

    writeLcdTop(wmain);
    writeLcdBtm(wdesc);
  } 
  else {
    writeLcdTop("Not Connected");
  }
}

void setup()
{
  Serial.begin(9600);
  lcd.begin(16, 2);

  screen_status = CITY;
  writeLcdTop("Select City");
  writeLcdBtm("> " + getCity());
}

void loop()
{
  lcd_key = read_LCD_buttons();  // read the buttons

    switch (lcd_key) {
  case btnRIGHT:
    {
      screen_status = WEATHER;
      getWeather();
      break;
    }
  case btnLEFT:
    {
      break;
    }
  case btnUP:
    {
      if (screen_status == CITY) {
        selected_city = (--selected_city + 6) % 6;
        Serial.println(selected_city);
        writeLcdBtm("> " + getCity());
        delay(600);
        break;
      }
    }
  case btnDOWN:
    {
      if (screen_status == CITY) {
        selected_city = (++selected_city) % 6;
        Serial.println(selected_city);
        writeLcdBtm("> " + getCity());
        delay(600);
        break;
      }
    }
  case btnSELECT:
    {
      screen_status = CITY;
      writeLcdTop("Select City");
      writeLcdBtm("> " + getCity());
      break;
    }
  case btnNONE:
    {
      break;
    }
  }
}