serin labsLicenses and compliance
This page lists the licenses for components used in firmware distributed by Serin Labs, followed by regulatory, safety, and trademark information for the Serin Controller. Refer to each project or manufacturer for its complete terms.
The ESPHome, HomeKit-compatible, and Serin Link dial builds are open source. Sources for all three are linked below, along with the Serin Link protocol and its ESPHome controller component. The Matter-compatible build is free to install but is not published; the table for it lists the third-party components it is built on, which is the part these licenses govern.
ESPHome firmware
The ESPHome .bin images are compiled with the ESPHome toolchain on the ESP-IDF framework, together with the Mitsubishi CN105 component stack.
| Component | License | Source & license |
|---|---|---|
| ESPHome | MIT + GPLv3 | Source · License |
| MitsubishiCN105ESPHome (echavet) | None declared | Source |
| esphome-mitsubishiheatpump (geoffdavis) | BSD-2-Clause | Source · License |
| SwiCago/HeatPump | GPL-3.0 / LGPL-3.0 | Source · License |
| ESP-IDF (build framework) | Apache-2.0 | Source · License |
- ESPHome is dual-licensed: its Python tooling is MIT, and its C++/runtime code, compiled into the firmware, is GPLv3.
- SwiCago/HeatPump ships the GPL-3.0 license text in its repository, while its README states LGPL-3.0.
- MitsubishiCN105ESPHome does not include a license file.
- Corresponding source for the exact ESPHome build is published at Serin-Labs/serin-cn105.
HomeKit-compatible firmware
The HomeKit-compatible .bin images are built on Espressif's HomeKit SDK and the ESP-IDF framework.
| Component | License | Source & license |
|---|---|---|
| esp-homekit-sdk (Espressif) | ESPRESSIF MIT License; mu_srp under Apache-2.0 | Source · License · mu_srp |
| ESP-IDF | Apache-2.0 | Source · License |
Matter-compatible firmware
The Matter-compatible .bin images are built on Espressif’s esp-matter SDK, the Connectivity Standards Alliance’s Matter SDK (connectedhomeip) that it wraps, and the ESP-IDF framework.
| Component | License | Source & license |
|---|---|---|
| esp-matter (Espressif) | Apache-2.0 | Source · License |
| Matter SDK (connectedhomeip) | Apache-2.0 | Source · License |
| ESP-IDF | Apache-2.0 | Source · License |
- The build is not Matter certified. It identifies itself with the SDK’s test attestation credentials rather than a certified device certificate, so every Matter controller warns about an uncertified accessory when it is added.
Serin Link firmware
The Serin Link dial firmware is built on the ESP-IDF framework and the LVGL graphics library, together with Espressif’s display, touch, knob, and button drivers for the VIEWE round display module it runs on. An assembled Serin Link ships with this firmware installed, and the Serin Link flashing page installs it on a bare display module over USB. The firmware is open source under the GNU General Public License, version 3, and its source is published at Serin-Labs/serin-link.
| Component | License | Source & license |
|---|---|---|
| ESP-IDF (build framework) | Apache-2.0 | Source · License |
| LVGL (graphics library) | MIT | Source · License |
| esp_lvgl_port (Espressif) | Apache-2.0 | Source · License |
| esp_lcd_sh8601 display driver (Espressif) | Apache-2.0 | Source · License |
| esp_lcd_touch and esp_lcd_touch_cst816s (Espressif) | Apache-2.0 | Source · License |
| esp_lcd_touch_cst820 (kodediy) | Apache-2.0 | Source · License |
| button (Espressif) | Apache-2.0 | Source · License |
| knob (Espressif) | Apache-2.0 | Source · License |
| libsodium (pairing keys) | ISC | Source · License · Espressif port |
| Panel initialization tables (VIEWE reference board support package) | MIT | Source · License |
| Plus Jakarta Sans (subset font data) | SIL Open Font License 1.1 | Source · License |
Monocypher 4.0.3, copied into the serin_link controller component |
BSD-2-Clause or CC0-1.0, at your option | Source · License |
- The Serin Link firmware is licensed GPL-3.0-only. Two parts of the repository carry their own terms, both listed in the table above: the Plus Jakarta Sans subsets under the SIL Open Font License 1.1, and the VIEWE panel initialization tables under MIT. The corresponding source for every build the flasher offers is the tagged release in Serin-Labs/serin-link.
- The Serin Link protocol and the
serin_linkESPHome controller component are open source under the Apache-2.0 license at Serin-Labs/serin-link-core. - Monocypher is copied into the controller component rather than pulled in as a dependency, because an ESPHome image can hold only one copy of libsodium and that copy belongs to ESPHome. It is dual-licensed, so you may take it under either license.
- The driver for the Sensirion SHT41 temperature and humidity sensor on the Serin Link carrier is written by Serin Labs and contains no third-party code.
Flashing tool
The flash page runs entirely in your browser. It drives Espressif’s esptool-js to write the firmware over USB, SparkMD5 to check the written bytes against the board’s flash checksum, and the Improv Serial SDK to hand the board your Wi-Fi credentials afterwards. These libraries are bundled with the page. The pairing and hotspot QR codes are drawn by qrcodejs, which the page loads from the cdnjs content delivery network with an integrity hash.
| Component | License | Source & license |
|---|---|---|
| esptool-js | Apache-2.0 | Source · License |
| SparkMD5 3.0.2 | WTFPL-2.0 | Source · License |
| Improv Wi-Fi Serial SDK (improv-wifi-serial-sdk) | Apache-2.0 | Source · License |
| qrcodejs 1.0.0 (davidshimjs) | MIT | Source · License |
QR label scanner
The compatibility page’s label scanner runs entirely in your browser, using the open-source qr-scanner library to read the QR code on your unit’s nameplate. Photos and camera frames never leave your device.
Regulatory & compliance
The Serin Controller is a smart controller for Mitsubishi mini-splits that connects to the CN105 service port inside the indoor unit. It is available as a DIY parts list or as a pre-assembled kit, and is built from commercially available M5Stack development kits rather than custom radio hardware. The sections below collect the regulatory, safety, and trademark information that applies to it.
FCC compliance
Serin Labs does not manufacture or modify any radio hardware. Both supported boards are FCC-certified by their manufacturer, M5Stack Technology Co., Ltd., and M5Stack lists CE, MIC, and FCC certification for each on its product certifications page.
| Board | FCC ID | Certification |
|---|---|---|
| M5Stack NanoC6 | 2AN3WM5NANOC6 | Device certification held by M5Stack. Contains the Espressif ESP32‑C6‑MINI‑1 radio module, itself FCC-certified as 2AC7Z‑ESPC6MINI1. |
| M5Stack Atom S3 Lite | 2AN3WM5ATOMS3 | AtomS3-series device certification held by M5Stack. The radio is integrated in the ESP32‑S3 chip; the FCC ID appears on the regulatory label on your unit. |
These devices comply with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) the device may not cause harmful interference, and (2) the device must accept any interference received, including interference that may cause undesired operation.
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, try one or more of the following measures:
- Reorient or relocate the receiving antenna.
- Increase the separation between the equipment and receiver.
- Connect the equipment to an outlet on a circuit different from the one the receiver is connected to.
- Consult the dealer or an experienced radio/TV technician for help.
Caution: changes or modifications to the radio hardware not expressly approved by the party responsible for compliance could void your authority to operate the equipment. Flashing open-source firmware does not modify the radio circuitry.
Safety & installation
Safety and installation information for every Serin Labs product now lives on the safety and installation page.
Trademarks & affiliations
Serin Labs is an independent company. It is not affiliated with, endorsed by, or certified by Mitsubishi Electric Corporation, Apple Inc., M5Stack Technology Co., Ltd., Sensirion AG, or VIEWE, the maker of the display module.
Serin Labs and its guides are not affiliated with or endorsed by Google LLC, Amazon.com, Inc. or its affiliates, or Samsung Electronics Co., Ltd. Platform names identify the apps and technologies used in the compatibility and setup instructions.
- Google and Google Home are trademarks of Google LLC.
- Amazon, Alexa, and all related marks are trademarks of Amazon.com, Inc. or its affiliates.
- SmartThings is a trademark of Samsung Electronics Co., Ltd.
- Mitsubishi Electric is a trademark of Mitsubishi Electric Corporation.
- Apple, Apple Home, HomeKit, Siri, HomePod, Apple TV, iPhone, and iPad are trademarks of Apple Inc., registered in the U.S. and other countries. The HomeKit-compatible firmware pairs with Apple Home using Apple's published HomeKit Accessory Protocol; the product is not MFi-certified and does not carry the “Works with Apple Home” badge.
- Matter is a trademark of the Connectivity Standards Alliance. The Matter-compatible firmware implements the Matter specification; it is not a certified Matter product, is not endorsed by the Alliance, and does not carry the “Works with Matter” badge.
- Home Assistant is a trademark of the Open Home Foundation. M5Stack is a trademark of M5Stack Technology Co., Ltd.
- Sensirion is a trademark of Sensirion AG. VIEWE is a trademark of its owner. Both names are used only to identify the parts a product is built from.
Materials & disposal
Like all electronics, the controller should not go in household trash at end of life. Take it to a local e-waste collection point; most US municipalities and many electronics retailers accept small electronics for recycling. Manufacturer compliance documentation for the boards is available from M5Stack.
DIY builds
If you source your own board and cable instead of buying the pre-assembled kit, regulatory compliance of those parts rests with their respective manufacturers. The boards above are the ones Serin Labs tests and recommends.
Contact
Questions about licenses, compliance, safety, or anything on this page: use the contact form, ask in Discord, or send a message to our Etsy shop.