# akospasztor/stm32-bootloader

Customizable Bootloader for STM32 microcontrollers. This example demonstrates how to perform in-application-programming of a firmware located on an external SD card with FAT32 file system.

Repository: https://github.com/akospasztor/stm32-bootloader
Canonical: https://ross.abutalabs.com/products/stm32-bootloader
Homepage: https://akospasztor.github.io/stm32-bootloader
Language: C
License: NOASSERTION
License Family: other
Topics: bootloader, in-app-programming, iap, flasher, stm32, stm32l4, stm32l476, mcu, microcontroller, flash, boot, demo, example, sd, microsd, fatfs, fat32, stm32l496, firmware, firmware-updater
Last push: 2022-12-02T09:35:41+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 3434, "days_push": 1370, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1054, forks 307 (observed 2026-08-28T04:03:24.124607+00:00)

## What it is
A customizable bootloader library for STM32 microcontrollers with example projects demonstrating firmware updates from an SD card with a FAT32 file system. It supports flash erase, programming, verification, checksum checks, and fail-safe error handling.

## Use cases
- update STM32 firmware from an SD card
- implement in-application programming (IAP) on a microcontroller
- build a fail-safe bootloader with checksum verification
- re-program a chip via ST's built-in bootloader without the BOOT pin
- port a bootloader to a custom STM32 board

## When to choose
- you need a customizable, well-documented bootloader for STM32L4 MCUs
- you want firmware updates delivered via SD card with FAT32
- you need flash protection checks and fail-safe update logic

## When to avoid
- you target non-STM32 or non-ARM Cortex-M microcontrollers without porting effort
- you need OTA updates over network rather than SD card
- you want a turnkey, actively developed product rather than a reference example

## Facets
- artifact type: library
- maturity: maintenance
- function: embedded, file-system, developer-tools
- domain: embedded-systems, hardware
- platform: embedded, c, cpp
- tags: bootloader, stm32, firmware-update, in-application-programming, sd-card, fat32, microcontroller, flash-programming, firmware

## Member repositories
- akospasztor/stm32-bootloader (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:24.124607+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T06:58:46.523382+00:00, confidence not recorded.
  - readme: https://github.com/akospasztor/stm32-bootloader (fetched 2026-08-28T04:03:24.124607+00:00, sha 3e582af93276)
  - homepage: https://akospasztor.github.io/stm32-bootloader (fetched 2026-08-29T13:00:20.806322+00:00, sha ce5585dbcde4)
- Data as of 2026-08-30T08:39:29.467469+00:00.