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atmega32u4-beetle SKILL.md skillA

atmega32u4-beetle from alexex1993/mcu-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned

mdr add alexex1993/mcu-skills/atmega32u4-beetle@git:20261030.816967f

Pins 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/avr/atmega32u4-beetle/SKILL.md
Versions recorded: 2
Latest version: git:20261030.816967f, committed Oct 30, 2026
First version recorded: Aug 30, 2026
Size: 19,718 bytes
Repository stars: 26
License: MIT

Firmware development for the Beetle — the CJMCU / DFRobot "Mini Arduino Leonardo" USB board (ATmega32U4 @ 16 MHz, 5 V, 21×28 mm, castellated pads) — its native USB (CDC serial + HID keyboard/mouse/joystick), Caterina bootloader and 1200 bps touch upload, ten exposed I/O pads, four PWM pins across Timer0/Timer1, five ADC channels, I2C on D2/D3, SPI on the back-side ICSP pads, 28 KB usable flash and 2.5 KB SRAM, and the PlatformIO + Arduino AVR core (`board = leonardo`) setup around them. Use…

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

# Beetle — Mini Arduino Leonardo (ATmega32U4)

Board-specific firmware knowledge. The Beetle is an ATmega32U4 with **native
USB** and **ten pads**, and almost every trap on it comes from one of those
two facts: USB means the programming interface is the sketch you are about
to replace, and ten pads means most of the Leonardo pin numbering the
compiler accepts goes nowhere on this board.

- `reference/board-hardware.md` — the complete board reference: pad
  inventory and full pin map, the sixteen I/O lines that are not brought
  out, power tree, clock and PLL, memory map, fuses and the Caterina
  bootloader **plus** a development guide (Part II: §8 toolchain, §9 USB and
  the two serial ports, §10 peripheral cookbook, §11 gotchas, §12 flashing
  and recovery, §13 symptom → cause → fix table).
- `reference/recipes.md` — copy-paste code: `platformio.ini`, `board.h`,
  non-blocking timing, USB-CDC that never blocks, `Serial1` on the TX/RX
  pads, I2C and SPI, the ADC channel map, external and pin-change
  interrupts, PWM and the timer map, Servo vs `tone()`, HID keyboard with
  its safety guards, EEPROM, power-down sleep with USB.
…

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint

mdr add alexex1993/mcu-skills/atmega32u4-beetle@sha256:426c00b248e3c531

The 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.

Badge

[![mdr](https://markdownregistry.com/badge/art_qpgncjql7tsn4scp.svg)](https://markdownregistry.com/a/art_qpgncjql7tsn4scp)

3 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 2 versions of this file, between Aug 30, 2026 and Oct 30, 2026, about one every 61 days.

version	committed	commit	size	audit
git:20261030.816967f latest	2026-10-30	816967f	19,718 B	A	view · diff
git:20260830.e379eda	2026-08-30	e379eda	19,653 B	A	view

Audit of the latest version

A 17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.

pass: Frontmatter block present
pass: Frontmatter declares a name
pass: Frontmatter declares a description
pass: Size between 200 bytes and 200 KB (19718 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

GitHub

alexex1993/mcu-skills · 26 stars · license MIT · pushed 2026-10-30 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_qpgncjql7tsn4scp
GET https://markdownregistry.com/api/v1/resolve?ref=alexex1993/mcu-skills/atmega32u4-beetle
GET https://markdownregistry.com/api/v1/blob/426c00b248e3c531c25aebae78b58e8e0f17d613f56aeb3b73013ef18a9a0b08

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.

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