nrobinson2000/LCD-Bitcoin-Monitor.ino

## bitcoin.json
{
  "eventName": "bitcoin",
  "url": "https://api.bitcoinaverage.com/ticker/global/USD/",
  "requestType": "GET",
  "mydevices": true
}

## LCD-Bitcoin-Monitor.ino
/*
 Bitcoin Monitor:

 This sketch shows the current Bitcoin price
 on an LCD.

  The circuit:
 * LCD RS pin to digital pin D0
 * LCD EN pin to digital pin D1
 * LCD D4 pin to digital pin D2
 * LCD D5 pin to digital pin D3
 * LCD D6 pin to digital pin D4
 * LCD D7 pin to digital pin D5
 * 10K resistor:
 * ends to +5V and ground
 * wiper to LCD VO pin (pin 3)
 * connect R/W (pin 5) to ground

*/
#include "LiquidCrystal/LiquidCrystal.h"

LiquidCrystal lcd(D0, D1, D2, D3, D4, D5);

void setup()
{
  lcd.begin(16,2);  // set up the LCD's number of columns and rows:

  lcd.print("Bitcoin Price:");  // Print a message to the LCD.

  Particle.publish("bitcoin");  // Trigger bitcoin webhook

  Particle.subscribe("hook-response/bitcoin/0", bitcoinHandler, MY_DEVICES);  // Subscribe to the webhook response

  Serial.begin(9600);  // Begin serial
}

void loop()
{
  if (millis()/1000 % 10 == 0) // Every ten seconds
  {
    Particle.publish("bitcoin");  // Trigger bitcoin webhook
  }
}

void bitcoinHandler(const char *event, const char *data)  // This is called when the Photon recives the webhook data.
{
 Serial.println(data);                                    // Print the data to serial for debugging
 String ask = String(getAskPrice(data));                  // Get the ask price of Bitcoin
 Serial.println(ask);                                     // Print it to serial
 lcd.setCursor(0, 1);                                     // Set the cursor to the second line
 lcd.print("            ");                               // Clear the second line
 lcd.setCursor(0,1);                                      // Reset cursor
 lcd.print(ask);                                          // Print the price of bitcoin
 lcd.print(" USD");                                       // Print "USD" after
}

String getAskPrice(String data)                                 // This function gets the value in the "ask:" part of the JSON.
{
    int kLocation = data.indexOf("k");                          // Find where the "k" of ask appears
    int commaLocation = data.indexOf(",", kLocation);           // Find where the comma after the value appears

   String value = data.substring(kLocation +4, commaLocation);  // The value is from 4 characters after where "k" is and right before where the comma is.
    return value;                                               // Return the ask price of Bitcoin
}
	{
	"eventName": "bitcoin",
	"url": "https://api.bitcoinaverage.com/ticker/global/USD/",
	"requestType": "GET",
	"mydevices": true
	}
	/*
	Bitcoin Monitor:

	This sketch shows the current Bitcoin price
	on an LCD.

	The circuit:
	* LCD RS pin to digital pin D0
	* LCD EN pin to digital pin D1
	* LCD D4 pin to digital pin D2
	* LCD D5 pin to digital pin D3
	* LCD D6 pin to digital pin D4
	* LCD D7 pin to digital pin D5
	* 10K resistor:
	* ends to +5V and ground
	* wiper to LCD VO pin (pin 3)
	* connect R/W (pin 5) to ground

	*/
	#include "LiquidCrystal/LiquidCrystal.h"

	LiquidCrystal lcd(D0, D1, D2, D3, D4, D5);

	void setup()
	{
	lcd.begin(16,2); // set up the LCD's number of columns and rows:

	lcd.print("Bitcoin Price:"); // Print a message to the LCD.

	Particle.publish("bitcoin"); // Trigger bitcoin webhook

	Particle.subscribe("hook-response/bitcoin/0", bitcoinHandler, MY_DEVICES); // Subscribe to the webhook response

	Serial.begin(9600); // Begin serial
	}

	void loop()
	{
	if (millis()/1000 % 10 == 0) // Every ten seconds
	{
	Particle.publish("bitcoin"); // Trigger bitcoin webhook
	}
	}

	void bitcoinHandler(const char event, const char data) // This is called when the Photon recives the webhook data.
	{
	Serial.println(data); // Print the data to serial for debugging
	String ask = String(getAskPrice(data)); // Get the ask price of Bitcoin
	Serial.println(ask); // Print it to serial
	lcd.setCursor(0, 1); // Set the cursor to the second line
	lcd.print(" "); // Clear the second line
	lcd.setCursor(0,1); // Reset cursor
	lcd.print(ask); // Print the price of bitcoin
	lcd.print(" USD"); // Print "USD" after
	}

	String getAskPrice(String data) // This function gets the value in the "ask:" part of the JSON.
	{
	int kLocation = data.indexOf("k"); // Find where the "k" of ask appears
	int commaLocation = data.indexOf(",", kLocation); // Find where the comma after the value appears

	String value = data.substring(kLocation +4, commaLocation); // The value is from 4 characters after where "k" is and right before where the comma is.
	return value; // Return the ask price of Bitcoin
	}