Video: https://youtu.be/BDN0qQKkOAo
Schematic: https://github.com/kakushinAU/BitcoinTracker/blob/main/ESP32_Bitcoin_Tracker_Schematic.pdf
Paper cutout pattern (A4 size): https://github.com/kakushinAU/BitcoinTracker/blob/main/Bitcoin_Tracker_Case-A4.pdf
Paper cutout pattern (Letter size): https://github.com/kakushinAU/BitcoinTracker/blob/main/Bitcoin_Tracker_Case-Letter.pdf
MegaCoreX board manager URL: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
Pololu USB AVR Programmer v2.1: https://www.pololu.com/product/3172
#include <WiFi.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>
#include <NTPClient.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#define NTP_OFFSET 39600 // In seconds 39600 = +11 hours
#define NTP_INTERVAL 60 * 1000 // In miliseconds
#define NTP_ADDRESS "1.asia.pool.ntp.org"
WiFiUDP ntpUDP;
NTPClient timeClient(ntpUDP, NTP_ADDRESS, NTP_OFFSET, NTP_INTERVAL);
Adafruit_SSD1306 display(128, 64, &Wire, 4);
const char* ssid = "mywifi";
const char* password = "mywifipassword";
String response = "";
String currentPrice = "";
String formattedTime = "";
volatile unsigned long lastPriceCheck = (millis() - 10000);
//JSON document
DynamicJsonDocument doc(2048);
void setup(void) {
Serial.begin(9600);
display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
display.clearDisplay();
display.setTextColor(WHITE);
WiFi.mode(WIFI_STA);
WiFi.begin(ssid, password);
display.setTextSize(1);
display.setCursor(0, 0);
display.print("CONNECTING TO: ");
display.println(ssid);
display.println();
display.display();
delay(500);
// Wait for connection
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
display.print(".");
display.display();
}
Serial.print("WiFi connected with IP: ");
Serial.println(WiFi.localIP());
display.clearDisplay();
display.setCursor(0, 0);
display.println("WiFi connected ");
display.println();
display.print("IP: ");
display.println(WiFi.localIP());
display.display();
delay(1000);
// Start time client and display
timeClient.begin();
}
String updateTime()
{
timeClient.update();
String formattedTime = timeClient.getFormattedTime();
return (formattedTime);
}
String checkBitcoinPrice()
{
HTTPClient http;
String request = "http://api.coindesk.com/v1/bpi/currentprice/BTC.json";
http.begin(request);
http.GET();
response = http.getString();
DeserializationError error = deserializeJson(doc, response);
if (error) {
Serial.print(F("deserializeJson() failed: "));
Serial.println(error.f_str());
return ("error");
}
http.end();
return (doc["bpi"]["USD"]["rate"].as<char*>());
}
void loop() {
String formattedTime = updateTime();
if ((lastPriceCheck + 10000) < millis()) {
currentPrice = checkBitcoinPrice();
lastPriceCheck = millis();
}
display.clearDisplay();
display.setTextSize(1);
display.setCursor(0, 0);
display.print(formattedTime);
display.println(" BITCOIN USD");
display.setTextSize(2);
display.setCursor(0, 24);
display.print(" BTC");
display.setCursor(0, 48);
display.print("$");
display.println(currentPrice);
display.display(); // write the buffer to the display
delay(100);
}