Embr

A firmware manager and flasher for Espressif chips on Windows.

Embr remembers every firmware you work with: where its files are, which addresses and parameters they are written with, and what each firmware is for. Firmware is organized into projects, firmware that follows an ESP-IDF or PlatformIO build always reflects the latest build, and every flash operation is recorded. Flashing is done by a built-in copy of esptool.

Features

Projects and firmware

• Organize firmware into projects and groups (for example, one group per board), or keep it standalone. Notes, tags and search are available for every firmware.
• Create firmware from .bin files, follow an ESP-IDF build directory, or follow one or more PlatformIO environments. Files and build folders can be dragged from File Explorer into the sidebar.

Builds that stay current

• Followed builds are checked again when a firmware is selected, when the window becomes active, before every flash, and periodically.
• A rebuild that only changes file contents is followed automatically. Any other change (entries, addresses, chip, ESP-IDF version, flash parameters) is listed and must be confirmed before flashing.
• An incomplete build, mixed build output or a target that changed without a rebuild is reported and cannot be flashed.

Recognition

• Each file is classified by its content: bootloader, app, partition table, otadata, merged image or file system image.
• Default addresses come from esptool, the partition table and the build output. Every address can be changed.
• Attachments (data the firmware reads from flash) can be placed by partition name or by address.

Checks before writing

• Connect & identify reads the chip, revision, MAC address, flash size and security state, then releases the port. Firmware that does not fit the identified chip is dimmed.
• A checklist covers address overlap, file consistency (name, path and SHA-256), chip and chip revision, flash size, reset settings and security features.
• Flashing is refused for chips with flash encryption, Secure Boot or Secure Download Mode enabled, and for images that do not match the chip.

Flashing and more

• Flash, erase the whole flash, and read flash to a file. Cancellation works at any stage and always releases the port.
• Merge a firmware into a single .bin image.
• Archive a fixed copy of a build, and move projects or firmware between computers as .embr packages.
• Every flash, erase and read operation is recorded: time, port, chip, MAC address, the files written with their SHA-256, the result and the equivalent esptool command.

Interface

• English and Simplified Chinese; light and dark themes, following the system by default.

Design principles

• Portable. Settings, data, logs and temporary files stay in the program folder. Nothing is written to %APPDATA% or the registry.
• Transparent. The equivalent esptool command for the selected firmware and port is always shown and can be copied.
• No lingering connections. Every operation opens its own connection and releases the port when it ends, so a serial monitor can use it right away.
• Safety checks are not bypassed. esptool's force option is never used.
• Your files stay yours. Deleting a project or firmware removes it from Embr only. It does not delete any .bin file or build output.

Requirements

• Windows 10 or Windows 11, x64.
• No Python installation is needed for the release package.

Installation

1. Download the latest release package from the Releases page.
2. Extract it to a writable folder (for example under Documents; not under Program Files).
3. Run Embr.exe.

Embr is not code-signed. On first start, Windows SmartScreen may show "Windows protected your PC"; choose More info, then Run anyway. Security software may also ask for confirmation.

Upgrading: replace Embr.exe and the _internal folder with those of the new version. Keep data, logs and settings.ini, which hold your projects, firmware, records and settings.

Getting started

1. Create a project with + New → New project.
2. Add firmware with + New: import an ESP-IDF build directory or a PlatformIO build, or create a firmware from .bin files. You can also drag files or a build folder into the sidebar.
3. Connect the device and select its port in the panel on the right.
4. Click Connect & identify and review the checklist.
5. Click Flash (Ctrl+Enter). Press Esc to cancel.

Supported chips and build systems

• Chips: the chips supported by the built-in esptool 5.3.1, except the ESP8266.
• ESP-IDF: build directories that contain flasher_args.json.
• PlatformIO: the Arduino framework with Arduino core 2.0.x on the official Espressif 32 platform, and the ESP-IDF framework. Projects using Arduino core 3.x (pioarduino) can be imported and flashed, but their support is not guaranteed. Arduino core 1.x is not supported.
• Not supported: chips with flash encryption, Secure Boot or Secure Download Mode enabled (these are detected and refused), reading or writing eFuses, and operating systems other than Windows.

Building from source

Requirements: Python 3.13 and uv.

uv sync

uv run embr

uv run pytest

When run from source, Embr keeps its data in the .run folder of the repository.

Documentation

• CHANGELOG.md: summary of the current version.
• docs/CHANGELOG.md: full list of changes in every version.
• LICENSE: the GNU General Public License, version 3.
• THIRD_PARTY_NOTICES: third-party software, fonts and icons included in Embr, with their licenses.

License and disclaimer

Copyright © 2026 @LuoIsHere

Embr is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. See LICENSE.

Embr is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. Flashing, erasing and reading flash change or expose the contents of a device. The author accepts no liability for any damage arising from the use of Embr, including damaged devices, lost data or erased or overwritten flash. Back up important data with Read flash… before writing to a device.

Acknowledgements and trademarks

Embr is built on esptool and Qt for Python (PySide6). It uses the HarmonyOS Sans font and Lucide icons. Full details and licenses are in THIRD_PARTY_NOTICES.

Espressif, ESP32 and ESP-IDF are trademarks of Espressif Systems (Shanghai) Co., Ltd. PlatformIO is a trademark of PlatformIO Labs. Embr is an independent project and is not affiliated with or endorsed by Espressif Systems or PlatformIO Labs.