ESP32 Bit Pirate Dock

TL;DR

The **ESP32 Bit Pirate Dock** is an open-source carrier/breakout board for the **Espressif ESP32-S3 DevKit**. Drop a DevKit into the dock, flash it with the [ESP32 Bit Pirate](https://github.com/geo-tp/ESP32-Bit-Pirate) firmware, and you get a multi-protocol hacking tool that can safely talk to peripherals at **1.8 V, 3.3 V, and 5 V** — and that plugs straight into the original **Bus Pirate ecosystem** of probes, cables, and adapters.

The DevKit stays a general-purpose dev board. The dock is what augments it to a *safe* and *practical* tool to connect to DUTs.

Thanks to PCBWay

Shoutout to PCBWay for sponsoring this project! They sponsored our project from the beggining. You can checkout their services on their website.You can build the whole project there, with the assembly, the bare PCB or just the device case.

Why we built this

The ESP32-S3 is a fantastic little chip for protocol work. It has the horsepower, the USB, the radios (Wi-Fi/BLE), and thanks to the ESP32 Bit Pirate firmware it can already sniff and drive I2C, SPI, UART, 1-Wire, JTAG/SWD, and a pile of radio protocols straight out of the box. So why add hardware at all?

Two reasons, and they're both about the physical layer:

**1. The ESP32-S3 works at 3.3 V.** Other devices under test may not. You'll sooner or later run into 1.8 V flash chips or 5 V buses. Hanging those directly off raw GPIO is how you let the magic smoke out of a DevKit. The dock adds **level/voltage translation** between the ESP32-S3 and the outside world, with selectable rails so you can match the target instead of relying on silicon tolerance.

**2. The Bus Pirate already has a great accessory ecosystem.** The classic Bus Pirate has years of cables, probe clips, and adapters built around its pinout. Rather than reinvent all of that, the dock is laid out so you can **reuse original Bus Pirate adapters and accessories** directly. If you've already got the probes, you don't have to buy them again.

So the dock isn't trying to replace the firmware or the DevKit — it sits *underneath* them and handles the boring-but-critical electrical reality that software can't fix.

A quick word on the firmware

Credit where it's due: the **ESP32 Bit Pirate** firmware is an open-source project by **geo-tp**, inspired by the legendary Bus Pirate. It turns an ESP32-S3 into a multi-protocol Swiss-army knife you drive from either a USB serial terminal or a browser-based **Web CLI**.

Out of the box it can:

• Sniff, send, and script **I2C, SPI, UART, 1-Wire, 2-Wire, CAN, and JTAG/SWD**
• Do I2C bus scanning/glitching, EEPROM and SPI flash dumping, UART baud auto-detection
• Handle **radio** work: Wi-Fi, Bluetooth/BLE, Sub-GHz, RFID, and IR (80+ protocols)
• Script interactions with Bus Pirate-style bytecode or Python over serial

The firmware runs on multiple devices, such as the ones mentioned at the beginning of the article, from M5Stack, or Seed Studio.

It runs on any ESP32-S3 board (if not supported, you can write your own config), and there's a one-click **Web Flasher** to install it. The dock is the hardware companion that makes all of that safe to point at real-world voltages.

What the dock actually does

At its core the ESP32 Bit Pirate Dock is a **carrier board** for the ESP32-S3 DevKit. Here's what it brings to the table:

• **Voltage/level translation** between the 3.3 V ESP32-S3 and external peripherals, supporting **1.8 V, 3.3 V, and 5 V** operation. This is the headline feature — it's what protects your DevKit and lets you talk to targets at their own logic level.
• **Bus Pirate adapter compatibility**, so the original ecosystem of cables, probe clips, and adapters plugs right in.
• **DevKit-agnostic footprint.** It's designed around the official **ESP32-S3-DevKitC-1**, but it also accommodates the many third-party DevKit clones, as long as the header geometry matches.
• An optional **3D-printed case** so the whole thing survives life in a bag instead of being a bare PCB.

One important note for anyone building this: the **ESP32-S3 DevKit is not included** in the hardware design — you source it separately (genuine Espressif, or a clone with matching header dimensions).

> **⚠️ Voltage warning:** Even with translation, only operate within the supported 1.8 V / 3.3 V / 5 V range. Connecting peripherals at other voltage levels can permanently damage your ESP32.

How it was built

**Design tooling.** The whole board is designed in **KiCad**, and the project is fully open-sourced: schematic, PCB layout source files, fabrication outputs (Gerbers), and the bill of materials all live in the repo. The schematic is also exported to a PDF for quick reference.

**The translation stage.** The defining design problem was the voltage translation path — getting clean, bidirectional signalling between the fixed 3.3 V ESP32-S3 and selectable 1.8 / 3.3 / 5 V rails on the target side, without slowing down the buses or introducing contention.

The IC which makes this possible is the TXS0108, but if you want a complete assesment of the components, take a look at the BOM [here](https://github.com/AndreiVladescu/ESP32-Bit-Pirate-Dock/blob/main/dock/BOM.csv).

**The enclosure.** There's a **two-piece case** designed to be printed on a standard FDM or SLA printer plus 3D models for the dock itself.

How to use the dock

Getting up and running is a five-minute job:

1. **Get an ESP32-S3 DevKit.** Genuine ESP32-S3-DevKitC-1 is the reference target; a clone works too as long as the header spacing matches the dock. The board needs **≥ 8 MB of flash** to run the firmware comfortably.

2. **Flash the ESP32 Bit Pirate firmware.** The easiest path is the project's **Web Flasher** — plug the DevKit into USB, open the flasher in a Chromium-based browser, and install in one click. Pick the **S3 DevKit** firmware build (there are variants, including an N16R8 build for 16 MB flash / 8 MB PSRAM boards). Keep in mind the firmware's default pin mapping is what the dock is wired around.

3. **Seat the DevKit in the dock.** Line up the headers and press it into place. If you printed the case, assemble it now.

4. **Select your target voltage.** Set the dock to **1.8 V, 3.3 V, or 5 V** to match the device you're probing. This is the step that keeps your hardware alive — match the target *before* you connect.

5. **Connect your Bus Pirate adapters / probes** and start driving it from the **serial terminal or Web CLI**. Scan an I2C bus, dump an SPI flash, sniff a UART — whatever the job is.

Open source & files

Everything you need to build, modify, or fabricate the dock is in the repository:

• `dock/kicad/` — KiCad design sources (schematic + layout)
• `dock/gerbers/` — PCB fabrication outputs
• `dock/schematic.pdf` — exported schematic reference
• `dock/BOM.csv` — bill of materials
• `3d_models/` — dock and case models

Other addons may be built, so stay tuned!

It's fully open hardware — so build one, improve it, and send a pull request.