WirelessAdapter

A wireless communication system built on two ESP32 using the ESP-NOW protocol. This project provides a transmitter-receiver pair for wireless data transmission.

Overview

This repository contains firmware for creating a wireless adapter system consisting of:

• Wireless Transmitter: Receives data from an HID, and packages and sends data wirelessly to the RX using ESP-NOW
• Wireless Receiver: Receives data wirelessly using ESP-NOW and delivers input-reports to a host PC.
• ESP-NOW MAC Utility: Helper utility to retrieve device MAC addresses for pairing
• Custom Components: Custom components and configuration shared across RX and TX architecture.

Features

• ESP-NOW Protocol: Fast, wireless communication between ESP32 devices
• Low Latency: Below 5ms RTT on Average
• Bidirectional Communication: Both transmitter and receiver components
• Modular Design: Structured with custom components and decoupled architecture for easier extension
• CMake Build System: Standard ESP-IDF build configuration

Project Structure

WirelessAdapter/
├── wireless_transmitter-2.0/   # Transmitter firmware
│   ├── main/                   # Main application code
│   ├── CMakeLists.txt          # Build configuration
│   └── structure.puml          # Architecture diagram
├── wireless_receiver-2.0/      # Receiver firmware
│   ├── main/                   # Main application code
│   ├── CMakeLists.txt          # Build configuration
│   └── structure.puml          # Architecture diagram
├── espnow_getmac/              # MAC address utility
│   ├── main/                   # Main application code
│   └── CMakeLists.txt          # Build configuration
└── custom_components/          # Reusable components

Prerequisites

• ESP-IDF: Espressif IoT Development Framework (version 4.x or 5.x)
• ESP32 Development Board: Any ESP32 series board that supports both ESP_NOW & USB_OTG
• USB Cable: For flashing and serial communication
• Python 3.x: Required by ESP-IDF

Installation

1. Install ESP-IDF

Follow the official ESP-IDF installation guide for your operating system.

2. Clone this Repository

git clone https://github.com/AndrewTheeFirst/WirelessAdapter.git
cd WirelessAdapter

Usage

Getting MAC Addresses

Before pairing devices, you need to know their MAC addresses:

cd espnow_getmac
idf.py build flash monitor

Note the MAC address displayed in the serial output.

Building and Flashing the Transmitter

cd wireless_transmitter-2.0
idf.py build flash monitor

Building and Flashing the Receiver

cd wireless_receiver-2.0
idf.py build flash monitor

Configuration

Pairing Devices

1. Flash the espnow_getmac utility to both ESP32 boards to obtain their MAC addresses
2. Update the MAC addresses in the transmitter and receiver code
3. Rebuild and reflash both devices

Architecture

The project uses PlantUML diagrams (structure.puml) in each component directory to document the architecture. View these files with a PlantUML viewer or plugin.

Author

Andrew (@AndrewTheeFirst)

Acknowledgments

• ESP-IDF framework by Espressif Systems
• ESP-NOW protocol documentation and examples