bitcointicker.ino

// bitcointicker v0.04 
//  buZz / NURDspace

// libraries used; 
//
//  * https://github.com/squix78/esp8266-oled-ssd1306
//  * https://github.com/tzapu/WiFiManager

#include <ESP8266WiFi.h>
#include <DNSServer.h>
#include <ESP8266WebServer.h>
#include <WiFiManager.h>
#include <ArduinoJson.h>

#include <Wire.h>
#include "SSD1306.h"


// Initialize the oled display for address 0x3c
// sda-pin=14 and sdc-pin=12
SSD1306   display(0x3c, D3, D4);

const char* host = "api.coindesk.com";
String url = "/v1/bpi/currentprice.json";

#define DEBUG       1

void setup() {

  display.init();
  display.setContrast(0x01);

  //display.setColor(0);
  display.fillRect(1,30,128,1);
  display.display();
  
  Serial.begin(115200);

  WiFiManager wm;
  wm.autoConnect();

  if (DEBUG) Serial.println("connected to wifi!");

  //display.drawRect(1,30,128,2);
//  display.flipScreenVertically();

}

WiFiClient client;
const int httpPort = 80;
int y = 0;
  
void loop() {

  StaticJsonBuffer<800> jsonBuffer;

  if (!client.connect(host, httpPort)) {
    if (DEBUG) Serial.println("connection failed");
    ESP.deepSleep(1000000);
    return;
  }
  
  client.print(String("GET ") + url + " HTTP/1.1\r\nHost: " + host + "\r\nConnection: close\r\n\r\n");
  delay(10);
  
  unsigned int i = 0;
  int n = 1;
  char json[500] ="{";
  while (!client.find("\"USD\":{")){delay(1);} 
  int timeout = millis() + 5000;
  while (client.available() == 0) {
    delay(1);
    if (timeout - millis() < 0) {
      if (DEBUG) Serial.println(">>> Client Timeout !");
      client.stop();
      ESP.deepSleep(1000000);
      return;
    }
  }
  while (i<600) {
    delay(1);
    if(client.available()) {
      char c = client.read();
      json[n]=c;
      if(c=='}') break;
      n++;
      i=0;
    }
    i++;
  }

  JsonObject& root = jsonBuffer.parseObject(json);

  if (!root.success()) {
    if (DEBUG) Serial.println("parseObject() failed");
    ESP.deepSleep(1000000);
  } else {

    const char* code = root["code"];
    double rate_float = root["rate_float"];  

    y++;
    if (y>20) y = 1;

    display.clear();
    display.setFont(ArialMT_Plain_24);
    display.drawString(15, 10, root["rate"]);
    display.display();

    if (DEBUG) Serial.println(rate_float);

    ESP.deepSleep(60000000); // 1 minute sleep
    //delay(25000); // Repeat 10 secs
  }
  while (client.available()) {
    delay(1);
    char bla = client.read();
  }
  client.stop();
  ESP.deepSleep(1000000);
}