Which browser should I use?

Use a desktop browser with Web Serial support on HTTPS or localhost. Chromium-based browsers are the most common option for this workflow.

What should I do after flashing?

Open the ESP32 Bit Pirate Web Serial Terminal, connect to the board and use the CLI to select a mode, scan buses, test pins or follow a recipe.

Why is my ESP32 board not detected?

Check that the USB cable supports data, close other serial monitors, use the correct USB port and enter bootloader mode with the board-specific BOOT or reset procedure.

Do I need to install a desktop flashing tool?

No. The firmware selection and flashing workflow runs from the web page, while the firmware binaries and manifests are loaded by the browser.

ESP32 Bit Pirate

Browser firmware installer

Flash the firmware in one click, then start using it.

Q: What does the ESP32 Bit Pirate Web Flasher do?

It installs ESP32 Bit Pirate firmware on supported ESP32-S3 boards and the ESP32-C5 Bus Expander directly from a compatible browser using Web Serial.

Install ESP32 Bit Pirate firmware on supported ESP32-S3 boards and the ESP32-C5 Bus Expander directly from your browser. This page is organized as a simple flow: flash the device, open the Web Serial terminal, then continue with practical recipes or theoretical documentation.

Select board and flash Open Web terminal

step by step

Recommended browser workflow

01 Flash firmware Select the exact board and launch the Web Serial installer. 02 Open terminal Connect to the flashed board and check the ESP32 Bit Pirate CLI. 03 Try a recipe Use practical examples for I2C, SPI, UART, GPIO, USB and more. 04 Read the reference Use the wiki for commands, modes and theoretical documentation.

Choose firmware

Select your ESP32 Bit Pirate target

Plug in your board with a USB cable and select the corresponding firmware below. The installer will guide you through the flashing process.

ESP32 Bit Pirate firmware (ESP32-S3)

ESP32 Bus Expander firmware (ESP32-C5)

Your web browser does not support Web Serial. Use a compatible desktop browser. This flasher needs HTTPS or localhost.

Select a board above.

Verify install

Open the Web Serial terminal after flashing

After the install, reconnect the board normally and open the terminal from the browser. Select USB Serial if the firmware asks for a terminal mode. It is the quickest way to confirm that the firmware booted and to start trying commands.

Web Serial terminal connected to ESP32 Bit Pirate after flashing.

Open Web Serial terminal →

> help
> mode i2c
> scan
> mode spi
> flash probe

Learn and troubleshoot

Choose the documentation style you need

The project keeps practical bench workflows and theoretical command references separate, so users can either follow a task or study a protocol mode in detail.

Practical recipe cards for hardware bench workflows.

Recipes

Task-based bench guides

Follow concrete workflows for wiring, commands, browser tools and repeatable hardware debugging tests.

Read recipes →

Documentation page with mode and command references.

Wiki

Modes and command reference

Use the wiki for mode pages, command syntax, firmware setup notes and deeper protocol explanations.

Open wiki ↗

quick checklist

Make the first flash predictable

Use a data USB cable

Charging-only cables can power the board without exposing a serial port. Use a known working data cable.

Select the right USB port

Some ESP32-S3 boards expose native USB and a separate UART bridge. Use the board port intended for flashing.

Close other serial tools

Serial monitors, IDEs or previous browser tabs can keep the port busy and prevent the installer from connecting.

board tips

Board-specific flashing tips

Use these hints when the browser cannot detect the target or the board does not enter download mode automatically.

Cardputer

Power off and unplug USB. Hold G0, then plug USB while still holding.

Stamp-S3

Hold BOOT before powering on or plugging in USB to enable flashing mode.

Atom-S3 Lite

Power on and press RESET for 3 seconds or until the LED blinks green.

Stick-S3

Hold POWER until the LED blinks green to enable flashing mode.

T-Embed

Hold the encoder center button, then press RESET. On CC1101 variants, the button is near the ESP32-S3.

S3 DevKit

Use the COM programming port. Hold BOOT, then power on or reset.

Xiao ESP32-S3

Hold BOOT before powering on or plugging in USB to enable flashing mode.

Linux users

If flashing fails, grant serial access with sudo setfacl -m u:$USER:rw /dev/ttyACM0 and adjust the device path if needed.

troubleshooting

Common Web Flasher issues

These checks cover the most frequent problems when using a browser-based ESP32-S3 firmware installer.

The browser does not show a serial port.

Use a desktop browser with Web Serial support, reconnect the board, try another data cable and close tools that may already own the serial port.

The board is visible but flashing fails.

Put the board in bootloader mode, select the exact board variant, then retry. On Linux, also check serial permissions for the active /dev/ttyACM* or /dev/ttyUSB* device.

The terminal opens but no text appears.

Reset the board after flashing, reconnect from the Web Serial terminal and confirm that the correct USB port is selected.

I selected the wrong board.

Return to the board selector and put your board in bootloader mode, choose the correct target and flash again.

Part of the ESP32 Bit Pirate ecosystem

After flashing, the same project gives you the firmware, browser tools, protocol recipes, documentation, scripts and companion hardware needed to explore buses, debug boards and automate repeatable bench workflows.

Firmware

ESP32 Bit Pirate

C++ firmware for wired buses, wireless protocols, USB adapters, device shells and hardware debugging commands.

View source ↗

Browser tools workspace with serial and hardware panels.

Web Tools

Serial, flash and capture tools

Desktop-style tools for Web Serial, SPI flash, AVR, STM32, ESP32, SUMP logic capture and BPIO2 GPIO/I2C/SPI.

Open tools →

Recipes

Practical bench documentation

Searchable task pages that explain wiring, commands and browser tool workflows.

Read recipes →

Documentation

Theoretical bench documentation

Mode pages, setup notes and command references for serial, web UI and adapter workflows.

Open wiki ↗

Automation

Scripts over serial

Automate scans, protocol checks, captures, reports and repeatable lab tasks.

Open Python Scripting Lab →

Grid of supported ESP32 development boards.

Supported targets

Choose before flashing

Compare supported ESP32-S3 boards, pin exposure, onboard peripherals and board-specific workflow limits.

Compare boards →

project

Powering the open-source ecosystem.

The Bit Pirate firmware is complemented by scripting, hardware dock, expansion boards, browser tools, documentation and practical embedded workflows for serial interfaces, protocol exploration and Wi-Fi connected debugging.