# B3603: reconstructing control-board behavior for replacement firmware

> B3603 investigates the buck converter's control board to support replacement STM8 firmware. The project maps MCU pins, display drivers and voltage and current control signals, includes board schematics, and provides firmware that the author reports is operational and serially controllable.

- Type: Case study
- Targets: Firmware
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-08
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/baruch/b3603>
- Primary source: <https://github.com/baruch/b3603/blob/1244057e9312ff9719ddc241c9c04df9ad7f62d6/README.md>
- Catalog page: <https://awesomerea.org/resources/b3603-case/>
- Record JSON: <https://awesomerea.org/resources/b3603-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/b3603-case/index.md)

## Requirements & limits

- **Prerequisites:** A B3603 unit, CP2102 USB-to-TTL adapter and STLink V2 programmer are listed as required components.
- **Testing evidence:** The author reports the replacement firmware is functioning and serially controllable.
- **License:** GPL-3.0 license.

## Primary sources

1. <https://github.com/baruch/b3603/blob/1244057e9312ff9719ddc241c9c04df9ad7f62d6/README.md>
2. <https://github.com/baruch/b3603/blob/1244057e9312ff9719ddc241c9c04df9ad7f62d6/stm8/PROTOCOL.md>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.