---
title: "Desky 2025"
slug: "desky_2025"
url: "https://haakony.no/posts/desky_2025"
date: "2025-04-07"
updated: "2026-06-08"
categories: ["projects"]
tags: ["c++", "arduino", "esp32", "btc", "desky"]
reading_time_minutes: 3
description: "In this project, I built a Bitcoin price tracker that shows real-time price data on a small AMOLED screen. It fetches Bitcoin price data from the CoinDesk API and displays it as an easy-to-read graph,…"
---

# Desky 2025

# Building a Bitcoin Price Tracker with ESP32-S3 and AMOLED Display

## Introduction

In this project, I built a Bitcoin price tracker that shows real-time price data on a small AMOLED screen. It fetches Bitcoin price data from the CoinDesk API and displays it as an easy-to-read graph, along with high/low values and percentage change.

<video src="https://haakony.no/media/1" controls width="600"></video>

## Hardware

I based this project on the [LILYGO T-Display-S3 AMOLED](https://www.banggood.com/custlink/3KGS4PpAQM) development board, which includes:

- ESP32-S3 microcontroller with WiFi and Bluetooth 5.0
- 1.9-inch AMOLED display with RM67162 controller
- Two programmable buttons
- Compact form factor perfect for desktop displays

![LILYGO T-Display-S3 AMOLED](https://imgaz.staticbg.com/images/oaupload/banggood/images/6C/81/ce4120bc-1df4-424e-a377-4cd4e02023ce.jpg.webp)

## Features

Here are the main features I wanted in this tracker:

1. **Real-time Price Updates**: Fetches the latest Bitcoin price data every 5 minutes
2. **Interactive Time Intervals**: Switch between 30-minute, 30-hour, and 30-day views using the buttons
3. **Visual Price Graph**: Displays price trends with auto-scaling for optimal visualization
4. **Key Price Information**: Shows high, low, and current prices
5. **Percentage Change**: Displays price movement with color coding (green for positive, red for negative)
6. **Clean User Interface**: Well-organized layout with clear labeling

## How It Works

The project is split into a few key parts:

### 1. Hardware Setup

The LILYGO T-Display-S3 AMOLED board gives me everything I need in one package. The ESP32-S3 handles WiFi and data processing, and the AMOLED display makes the output look sharp and vibrant.

### 2. Software Architecture

I structured the code to:
- Initialize the display and WiFi connection
- Fetch Bitcoin price data from the CoinDesk API
- Process and store the historical price data
- Draw the graph and price information on the display
- Handle button inputs for switching between time intervals

### 3. Data Visualization

I draw the graph using the TFT_eSPI library, which is efficient and works well with the AMOLED display. The price data is auto-scaled so the graph stays useful even when the market moves a lot.

### 4. User Interaction

I use the two onboard buttons for interaction:
- Button 1: Cycles through different time intervals (30m → 30h → 30d)
- Button 2: Manually refreshes the data

## Technical Challenges and Solutions

While building it, I ran into a few challenges and solved them:

1. **Display Initialization**: The AMOLED display required specific initialization parameters to work correctly
2. **Memory Management**: ESP32 has limited RAM, so we optimized data structures and drawing routines
3. **Screen Refresh**: We implemented proper sprite clearing to prevent artifacts and ensure smooth updates
4. **API Rate Limiting**: Added error handling for API requests to manage potential rate limits
5. **Button Debouncing**: Implemented proper debounce logic to ensure reliable button inputs

## Code Structure

I kept the code modular, with separate functions for:
- Display initialization and management
- Data fetching and parsing
- Graph drawing and visualization
- Button handling and user interaction

I also used a template-based approach for environment variables so sensitive values like API keys stay out of source code.

## Future Enhancements

There are a few obvious ways I could expand this:

1. **Additional Cryptocurrencies**: Add support for tracking multiple cryptocurrencies
2. **Custom Alerts**: Implement price alerts for significant movements
3. **More Time Intervals**: Add additional time ranges like 7-day or 1-month views
4. **Weather Integration**: Combine with weather data for a multi-purpose display
5. **Cloud Integration**: Store historical data in the cloud for longer-term analysis

## Conclusion

This project is a good example of what I can do with an ESP32-S3 and a small AMOLED display. By combining hardware and software in a simple way, I ended up with a compact desktop tool that gives me real-time Bitcoin market data at a glance.

It also shows how practical and useful modern microcontroller projects can be when they are connected to live internet data.

## Resources

- [GitHub Repository](https://github.com/haakony/desky_2025_2)
- [LILYGO T-Display-S3 AMOLED](https://www.banggood.com/custlink/3KGS4PpAQM)
- [LILYGO T-Display-S3 AMOLED Documentation](https://github.com/Xinyuan-LilyGO/T-Display-S3-AMOLED)
- [TFT_eSPI Library](https://github.com/Bodmer/TFT_eSPI)