stm32f401rc-blackpill SKILL.md skillA
stm32f401rc-blackpill from alexex1993/mcu-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add alexex1993/mcu-skills/stm32f401rc-blackpill@git:20261030.816967fPins git:20261030.816967f in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- alexex1993/mcu-skills
- Path
skills/stm32/stm32f401rc-blackpill/SKILL.md- Versions recorded
- 2
- Latest version
- git:20261030.816967f, committed Oct 30, 2026
- First version recorded
- Oct 15, 2026
- Size
- 14,510 bytes
- Repository stars
- 26
- License
- MIT
Firmware development for the 40-pin "Black Pill"-format board with an STM32F401RCT6 (STM32F401RC, LQFP64, 256 KB flash, 64 KB RAM, 84 MHz) that ships with the WeAct Studio HID Bootloader (USB 0483:572A, flash 0x08000000-0x08003FFF, app at 0x08004000) — its PC13 LED, KEY button on PA0, 25 MHz HSE, USB-C on USB_OTG_FS, and the PlatformIO + STM32Cube HAL setup around them, including a USB CDC virtual COM port for printf debugging. Use when working on this board, an unbranded F401RCT6 Black Pill…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# STM32F401RCT6 "Black Pill" with the WeAct HID bootloader Board-specific firmware knowledge. The board's defining feature is not the chip but what sits in the first 16 KB of its flash: WeAct's HID bootloader. Almost every failure on this board comes from code that assumes it owns 0x08000000 and a freshly reset chip — neither is true here. Read the reference files rather than guessing. - `reference/board-hardware.md` — the hardware (MCU, pins, header, clocks, memory map with the bootloader), a full description of the bootloader's behaviour and protocol, PlatformIO configuration, flashing and recovery routes, and a symptom → cause → fix table (§9). - `reference/recipes.md` — copy-paste code taken from `template/`: `platformio.ini`, the linker-script change, the hand-off `Reset_Handler`, the 84/48 MHz clock tree, the USB CDC console, the flasher, bootloader reinstall. - `template/` — a **working PlatformIO project**: blink + USB CDC `printf` console, flashed over USB through the HID bootloader without touching a button, plus a scaffold script that can also produce a bare blink. See `template/README.md`. ## Orientation | | | |---|---| …
Read the whole file at its exact version.
How to install
mdr add alexex1993/mcu-skills/stm32f401rc-blackpill@sha256:0a0b1c6251bda0c2The line at the top of this page pins the label git:20261030.816967f, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_npjrsq7cdwnijdqv)
1 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Oct 15, 2026 and Oct 30, 2026, about one every 15 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261030.816967f latest | 2026-10-30 | 816967f | 14,510 B | A | view · diff |
| git:20261015.48b56f8 | 2026-10-15 | 48b56f8 | 14,484 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (14510 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
alexex1993/mcu-skills · 26 stars · license MIT · pushed 2026-10-30 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_npjrsq7cdwnijdqv GET https://markdownregistry.com/api/v1/resolve?ref=alexex1993/mcu-skills/stm32f401rc-blackpill GET https://markdownregistry.com/api/v1/blob/0a0b1c6251bda0c291c687ff0a20af8b54b9b6877d3e6933e3129e94a42143a9
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.