Bitcoin_Price_Ticker_using_ESP8266_WiFi_Module.ino

/*
 * Bitcoin Price Ticker using ESP8266 WiFi Module
 * www.KendrickTabi.com
 * http://www.kendricktabi.com/2015/06/bitcoin-price-ticker-using-esp8266-wifi-module.html
 */

#include <SoftwareSerial.h>
 
#define SSID "mySSID" // insert your SSID
#define PASS "myPassword" // insert your password

String id;
String value;

void setup() {
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }

  Serial1.begin(9600);
  while (!Serial1) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }
  
  delay(1000);
  
  Serial.println("Bitcoin Price Ticker");
  Serial.println("by: www.KendrickTabi.com");
  Serial.println();
  Serial1.println("AT+RST"); // restet and test if module is redy
  Serial.println("Resetting the module...");
  delay(1000);
  if(Serial1.find("ready")) {
    Serial.println("WiFi - Module is ready");
  }
  else{
    Serial.println("Module dosn't respond. Please restart.");
    return;
  }
  delay(3000);
  
  Serial1.println("AT+CWMODE=1");
  String cmd="AT+CWJAP=\"";
  cmd+=SSID;
  cmd+="\",\"";
  cmd+=PASS;
  cmd+="\"";
  Serial1.println(cmd);
  delay(5000);
  if(Serial1.find("OK")){
    Serial.println("OK, Connected to WiFi.");
    Serial.println();
  }
  else{
    Serial.println("Can not connect to the WiFi.");
    Serial.println();
    return;
  }
  
  delay(5000);
  Serial1.println(F("AT+CIPMUX=0")); // set to single connection mode
}

void loop() {
  String cmd = "AT+CIPSTART=\"TCP\",\"";
  cmd += "api.coindesk.com";
  cmd += "\",80";
  Serial1.println(cmd);
  if(Serial1.find("Error")) return;
  cmd = "GET /v1/bpi/currentprice.json";
  cmd += " HTTP/1.0\r\nHost: api.coindesk.com\r\n\r\n";
  
  Serial1.print("AT+CIPSEND=");
  Serial1.println(cmd.length());
  
  if(Serial1.find(">")){
    Serial.println("Connection established.");
  }
  else{
    Serial1.println("AT+CIPCLOSE");
    Serial.println("Connection timeout.");
    delay(1000);
    return;
  }
  
  Serial1.println(cmd);
  
  unsigned int i = 0; //timeout counter
  int n = 1; // char counter
  char json[500] ="{";
  while (!Serial1.find("\"USD\":{")){} 
  while (i<600) {
    if(Serial1.available()) {
      char c = Serial1.read();
      json[n]=c;
      if(c=='}') break;
      n++;
      i=0;
    }
    i++;
  }
  
  Serial.println(json);
  id += json;
  value += json;
  
  id = id.substring(9,12);
  Serial.print(id);
  Serial.print("= ");
  
  value = value.substring(99,106);
  Serial.println(value);
  Serial.println();
  
  id="";
  value="";
  delay(60000); // Repeat every minute
}