Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/iot-forge/m5stack-skills/cardputer-advnpx skills add iot-forge/m5stack-skills --skill cardputer-advgit clone --depth 1 https://github.com/iot-forge/m5stack-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/iot-forge/m5stack-skills/cardputer-adv)<a href="https://agentmods.dev/skills/iot-forge/m5stack-skills/cardputer-adv"><img src="https://agentmods.dev/badge/skills/iot-forge/m5stack-skills/cardputer-adv.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00217 | $0.01921 |
| Opus 5 | $0.00109 | $0.00960 |
| Sonnet 5 | $0.00043 | $0.00384 |
| Haiku 4.5 | $0.00022 | $0.00192 |
Grade A, and why
m5stack-cardputer-adv scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 118 lines — stays where its author put it; the contents beside it link to each section on GitHub.
M5Stack Cardputer Adv development
The Cardputer Adv is an ESP32-S3-based pocket computer from M5Stack: a 56-key keyboard, 1.14" IPS screen, IMU, mic/speaker, Grove and EXT expansion ports, microSD, and a 1750mAh battery, all in an 84 x 54 x 19.6mm shell. Official docs: https://docs.m5stack.com/en/core/Cardputer-Adv
Use this skill to write correct firmware for it (Arduino, PlatformIO, ESP-IDF, or UIFlow2/MicroPython), to explain what a pin or peripheral does, or to debug hardware-facing code (wrong I2C address, keyboard not responding, display not initializing, etc).
Important: this is not the original Cardputer
M5Stack sells two boards with very similar names and the same enclosure shape. Don't assume code for one works unmodified on the other.
| Subsystem | Cardputer (original) | Cardputer Adv |
|---|---|---|
| Keyboard | GPIO scan matrix, no I2C | TCA8418 I2C keypad controller + interrupt on G11 |
| Audio | NS4168 I2S amp + SPM1423 PDM mic | ES8311 codec (I2C control + I2S data) + NS4150B amp |
| IMU | none | BMI270 (I2C, 6-axis) |
| Module | Stamp-S3 | Stamp-S3A |
If the user's code touches raw GPIO pin numbers for the keyboard or mic, double-check which board it targets — a sketch written for the original Cardputer's GPIO matrix keyboard will not read keys correctly on the Adv, which exposes its keyboard only through the TCA8418 over I2C.
The good news: if you use the official M5Cardputer Arduino library (which
wraps M5Unified/M5GFX), the same high-level API (M5Cardputer.Keyboard,
.Display, .Speaker, .Mic, .Imu) works on both boards — the library
detects which hardware is present and talks to the right chip underneath.
Prefer that library over hand-rolled register access unless the user is
specifically doing bare-metal ESP-IDF work or needs something the library
doesn't expose.
Quick specs
- SoC: ESP32-S3FN8, dual-core Xtensa LX7 @ 240MHz, 8MB flash
- Display: 1.14", 240x135px, ST7789V2 driver, SPI
- Keyboard: 56 keys (4 rows x 14 cols), TCA8418 I2C controller, 160gf keypress
- IMU: BMI270, 6-axis, I2C
- Audio: ES8311 codec, MEMS mic (65dB SNR), NS4150B amp + 8Ω/1W speaker, 3.5mm jack
- Storage: microSD slot
- Expansion: Grove port (HY2.0-4P), EXT 2.54-14P header (SPI/I2C/UART)
- Connectivity: WiFi + BLE (integrated in ESP32-S3)
- Battery: 1750mAh Li-po; ~120-155mA active draw depending on radio use; 0.23µA standby (power switch off)
- Other: IR emitter, magnetic back, LEGO-compatible mounting holes, lanyard hole
- Size / weight: 84.0 x 54.0 x 19.6mm, 81.0g
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 118 lines · 217 tokens per session scan A 725165a0251c
m5stack-cardputer-adv is a skill published in the GitHub repository iot-forge/m5stack-skills (2 stars, last pushed 10d ago), licensed MIT. It adds 217 tokens to every session and 1,921 once invoked, about $0.0011 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
nucleo-release
Build, gate, and ship NucleoOS to the Cardputer — firmware via OTA and the web/SD payload via the device file API. Use when the user asks to release, deploy, flash, OTA, sync the SD, or push a web app to the device. Covers the one-command release, firmware-only and SD-only paths, and the gotchas (PIN, .gz shadowing…
nucleo-native-app
Scaffold and implement a NucleoOS native firmware app (C++) correctly — anti-flicker, poll handler, RAM discipline, input routing, registration. Use when creating or fixing a native app in firmware/components/nucleoapp/.
nucleo-anima-debug
Debug and develop NucleoOS firmware/ANIMA logic on the PC without flashing — the host harness compiles the real C and runs it locally. Use when working on ANIMA (the offline NL assistant), retrieval cascade, NLU, knowledge graph, or any firmware logic, and when deciding how to verify a change. Lists the gate suites to…
read_touch
Read smoothed capacitive touch sensor values from one or more input GPIO channels. Use when the user asks for touch smooth values, capacitive touch channel readings, or smoothed touch data. Requires explicit gpios and boardhardwareinfo before assigning GPIOs.
embedded-engineer
(oh-my-embedded) Senior embedded systems engineer. ESP32/STM32, FreeRTOS, RF design, power management, peripheral interfaces. Use for any embedded/firmware/electronics/hardware question.
firmware-debugger
(oh-my-embedded) Firmware debugging via GDB and serial monitor. Breakpoints, memory inspection, stack traces, JTAG/SWD. Requires debug probe.