Shard

# Shard - ESP32-S3 Development Board

![Shard Board](https://github.com/user-attachments/assets/2b6138d2-c1b5-407c-aaca-fd7eff1a97fd)

[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
[![KiCad](https://img.shields.io/badge/KiCad-8.x-blue.svg)](https://kicad.org/)
[![ESP32-S3](https://img.shields.io/badge/ESP32-S3-red.svg)](https://www.espressif.com/en/products/socs/esp32-s3)

**Shard** is a simple and open-source ESP32-S3 development board designed for prototyping and embedded development. Featuring a compact form factor with comprehensive GPIO access and high-performance specifications.

## Table of Contents

- [Features](#features)
- [Specifications](#specifications)
- [Getting Started](#getting-started)
- [Programming](#programming)
- [Pinout](#pinout)
- [Hardware Design](#hardware-design)
- [Contributing](#contributing)

## Features

- **High Performance**: ESP32-S3 dual-core processor with WiFi and Bluetooth capabilities
- **Generous Memory**: 16 MB Flash storage
- **Rich I/O**: 21 configurable GPIO pins with UART, SPI, and I2C support
- **Visual Feedback**: Built-in addressable RGB LED (Neopixel)
- **Flexible Power**: Supports external power supply up to 16V
- **Compact Design**: Small form factor (4.6 × 4.8 cm) ideal for prototyping

## Specifications

| Feature | Specification |
|---------|---------------|
| **MCU** | ESP32-S3 dual-core Xtensa LX7 |
| **Flash Memory** | 16 MB |
| **GPIO Pins** | 21 |
| **Connectivity** | WiFi 802.11 b/g/n, Bluetooth 5.0 LE |
| **Power Input** | 3.3V - 16V (external), 5V (USB) |
| **Dimensions** | 46 × 48 mm |
| **LED Indicator** | Addressable RGB (Neopixel) |
| **Buttons** | Reset, Boot |

## Getting Started

### Power Supply

- **USB Power**: 5V via USB-C
- **External Power**: 3.3V - 16V via power pins

## Programming

### Upload Process

Since the board lacks a built-in USB-UART bridge, firmware uploads require manual boot sequence:

1. **Initiate Upload**: Start the upload process in your IDE
2. **Enter Download Mode**:
   - Press and hold the **RESET** button
   - Press and release the **BOOT** button
   - Release the **RESET** button
3. **Complete Upload**: Wait for upload to finish
4. **Exit Download Mode**: Press **RESET** button to start execution

### Arduino IDE Setup

#### Installation

1. Install the ESP32 board package:
   - Open Arduino IDE 2.x
   - Go to **File** → **Preferences**
   - Add to Additional Board Manager URLs:

     ```text
     https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
     ```

   - Go to **Tools** → **Board** → **Boards Manager**
   - Search for "esp32" and install

2. Board Configuration:
   - Select **Tools** → **Board** → **ESP32 Arduino** → **UM-PROS3**
   - Set **Upload Speed**: 921600
   - Set **Flash Size**: 16MB
   - Set **Partition Scheme**: Default 16MB with spiffs

### PlatformIO Setup

Create a `platformio.ini` file in your project root:

```ini
[env:env:esp32-s3-shard]
platform = espressif32
board = shard ; or `um-pros3`
framework = arduino

board_build.flash_mode = dio
board_build.flash_size = 16MB
board_build.partitions = default_16MB.csv
```

To use my custom board config file `shard.json`, download it and place it under the `boards` folder inside your project.

#### Optional Custom Partition Table

This is the default partition table (`partitions.csv`):

```csv
# Name , Type, SubType, Offset  , Size    , Flags
nvs    , data, nvs    , 0x9000  , 0x5000  , 
otadata, data, ota    , 0xe000  , 0x2000  , 
app0   , app , ota_0  , 0x10000 , 0x700000, 
app1   , app , ota_1  , 0x710000, 0x700000, 
spiffs , data, spiffs , 0xe10000, 0x1F0000, 
```

To specify a different partition table, modify the `partitions` entry inside `shard.json`

Follow the [upload process](#upload-process) when programming with PlatformIO.

## Pinout

### Pin Mapping Summary

| Function | GPIO Pins | Notes |
|----------|-----------|-------|
| **Digital I/O** | GPIO1-21 | 3.3V logic level |
| **ADC** | GPIO1-14 | 12-bit resolution |
| **Touch** | GPIO1-14 | Capacitive touch sensing |
| **SPI** | Configurable |  |
| **I2C** | Configurable |  |
| **UART** | Configurable | TX, RX |
| **PWM** | All GPIO |  |
| **RGB LED** | GPIO21 | Built-in addressable LED |

## Hardware Design

All design files are open-source and available in this repository:

- **Schematic**: `Shard.kicad_sch` or `Shard.pdf`
- **PCB Layout**: `Shard.kicad_pcb`
- **Gerber Files**: `shard-gerbers/`
- **Bill of Materials**: `Shard_BOM.xlsx`
- **Part Placement**: `Shard_CPL.xlsx`

## Contributing

Feel free to open a pull request or an issue

## References

- [ESP32-S3 Hardware Design Guidelines](https://docs.espressif.com/projects/esp-hardware-design-guidelines/en/latest/esp32s3/esp-hardware-design-guidelines-en-master-esp32s3.pdf)
- [ESP32-S3 Datasheet](https://www.espressif.com/sites/default/files/documentation/esp32-s3_datasheet_en.pdf)
- [Arduino ESP32 Documentation](https://docs.espressif.com/projects/arduino-esp32/en/latest/)

---

This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.