ESP32 Bus Expander is a companion firmware designed to extend the capabilities of the ESP32 Bit Pirate.
It runs on an ESP32-C5 and connects to the main Bit Pirate device via UART, adding hardware features that are not available on the primary board.
The first goal of this expansion module is to provide 5 GHz Wi-Fi support, which is not available on most ESP32-S3 based boards. Future versions may also expose 802.15.4 radio protocols such as Zigbee and Thread.
To flash it, use the webflasher and select ESP32 Bus Expander (ESP32-C5): ESP32 Bit Pirate Web Flasher.
Many boards used with the ESP32 Bit Pirate only support 2.4 GHz Wi-Fi.
The ESP32 Bus Expander solves this limitation by adding a secondary device that provides additional radio capabilities.
The architecture becomes:
ESP32 Bit Pirate (ESP32-S3)
│
│ UART
▼
ESP32 Bus Expander (ESP32-C5)
- The Bit Pirate remains the main interface (CLI, scripts, tools).
- The Bus Expander provides additional wireless hardware features.
It allows new radio technologies to be added without changing the main firmware.
- Wi-Fi 5 GHz support
- Connected to the Bit Pirate via UART
- Works as a radio coprocessor
- Can be controlled from the Bit Pirate firmware
With the expander connected, the Bit Pirate can interact with networks that require 5 GHz connectivity.
Future firmware versions may extend support for additional radio protocols available on the ESP32-C5, including:
- Zigbee (IEEE 802.15.4)
- Thread
- Matter
- Other 802.15.4 based protocols
This will allow the ESP32 Bit Pirate ecosystem to interact with IoT wireless networks and devices.
The Bus Expander is designed for ESP32-C5 based boards.
Minimum requirements:
- ESP32-C5 chip (4MB flash, no PSRAM needed)
- UART connection to the Bit Pirate device
The Bus Expander connects to the main Bit Pirate using UART.
Typical wiring:
| Bit Pirate | Bus Expander |
|---|---|
| RX | 9 |
| TX | 10 |
| GND | GND |
Once connected, the Bit Pirate firmware can detect and communicate with the expander. You can set the UART config in the platformio.ini file.
⚠️ RF Usage Warning: Always respect local regulations regarding wireless transmissions.
The evil command with features such as sniffing, deauthentication, and handshake capture comes from the Evil Firmware