In development · Hardware and firmware

STM32 Platform

A firmware platform with no vendor code in the build. You can read every layer that touches the silicon.

Get in touch See it working

PLINK · one request, byte for byte, on each transport

Link frame 10 bytes · CRC 0x8172

1004410300018F827281

Read one parameter: count 1, then id 0x828F, little-endian.

UART · USB CDC COBS, then 00 · 12 bytes

051004410306018F82728100

CAN 29-bit ID 15 dst src ch · 3 frames

FF	`1501FE00`	100A100441030001
FC	`15FE0100`	300000
CF	`1501FE00`	218F827281

Real frames from the platform’s golden test vectors, which the C firmware and the Python host are both tested against. The UART and CAN encodings are worked out with the spec’s rules, in your browser.

Title: STM32 Platform
Dwg no.: Q1-001
Rev: 2026.1
Status: In development
Drawn by: DWMM Holdings

Notes

What it does.

A full firmware platform for STM32 G4, L4 and H7 chips. It provides the HAL, the kernel, the host tools and the wire protocol, so an application repository only needs its own source files and a YAML config.

01
A hand-written HAL and kernel, with no vendor code running on the chip
02
Fetches the toolchain and builds with CMake, driven by a device database generated from CMSIS-SVD
03
A wire protocol over UART, CAN and USB, plus a desktop app that speaks it and flashes boards
04
A CANopen stack tested against python-canopen on real hardware
05
Over 1,400 commits, the biggest single codebase in the portfolio

What’s in the repository

Every layer, written here.

The specification (docs/STM32_PLATFORM_SPEC.md) decides what the code does. Each area has a section in it and a folder in the tree. There’s no tagged release yet.

Area	Spec	Where
Toolchain fetch and CMake build	§3	`cmake/, tools/sp/toolchain.py`
Device database: G473, H743, L432, L476	§4	`devices/db/`
Hardware config, clock solver, GUI editor	§5	`tools/sp/hwcfg/, tools/sp/gui/`
Board ID by voltage divider	§6	`core/platid/`
HAL	§7	`core/hal/`
Kernel, LITE and FULL	§8	`core/os/`
DAQ annotations and runtime	§10, §12	`tools/sp/daqgen/, core/daq/`
PLINK on UART, CAN and USB	§11	`core/plink/`
Display app	§13	`tools/sp/display/`
Bootloader	§14	`core/boot/`
Host CLI and MCP server	§15, §16	`tools/sp/cli.py, tools/sp/mcp/`
CAN message database, CANopen	§17	`core/cancom/`

An application

Your code, your YAML, and the platform as a submodule.

An app repository holds its own code, an app.yaml, and one YAML file per board. The platform comes in as a git submodule at platform/, and two small frozen files hand the build over to it. A config mistake stops the build with a file, line and column.

my-app/
├── CMakeLists.txt     # frozen, three lines
├── CMakePresets.json  # frozen, includes the platform’s
├── app.yaml           # name, chip, sources, kernel, PLINK
├── configs/
│   └── default.yaml   # pins, clocks, peripherals
├── src/main.c
└── platform/          # this repository

$ cmake --preset debug && cmake --build --preset debug
$ sp flash
$ sp display --connect serial:COM5

Specification

What it’s built with, and when.

Pulled from the repository each time this site is built.

State: In development
Discipline: Hardware systems
Shape: Hardware and firmware
Started: Aug 2026
Last change: Sep 2026
Commits: 1,430

C
Python
CMake
CMSIS
Rust
Tauri
ARM Cortex-M

Python 66%
C 28%

Related work

Built alongside STM32 Platform

CAN-to-USB A CAN bus to USB adapter, board and firmware LED Matrix Driver A 128×64 RGB LED panel driver in SystemVerilog on an iCE40 Button Box Circuit board and enclosure for a sim-racing button box KiCad Libraries A shared KiCad library for in-house parts

Build on STM32 Platform

Ask about licensing the platform, bringing up a board, or contract firmware work.

Email dmoore@dwmmholdings.com How it works