Hardware Kit

ARM MCU (STM32)

32-bit Cortex-M microcontrollers with DMA, timers, and optional FPU. Ideal for mid-tier autonomy where you need determinism plus more compute headroom.

Cortex-M RTOS-ready Deterministic

Compute

Cortex-M3/M4/M7 @ 72-480 MHz

Memory

Flash 64 KB-2 MB, SRAM 20 KB-1 MB

OS/RTOS

Bare-metal or FreeRTOS

Toolchain

arm-none-eabi-gcc, CMSIS, STM32Cube

Power

3.3V, tens to hundreds of mA

Typical Boards

Nucleo / Discovery boards for rapid bring-up
STM32F4/F7/H7 custom boards for performance
Low-power L-series for battery-focused builds

Toolchain + Build Profile

Compiler: arm-none-eabi-gcc
SDK: CMSIS + STM32Cube HAL/LL
Debug: ST-Link, OpenOCD, SWD

cmake .. -DTARGET=stm32
cmake --build .

Pin-Level + Electrical

3.3V logic; some pins are 5V tolerant (check datasheet)
Alternate functions: GPIO multiplexed with UART/I2C/SPI/CAN
Timers: PWM generation and encoder inputs
ADC: 12-16 bit; DMA for high-rate sampling
Debug: SWD (SWCLK/SWDIO) + NRST

Sensors + Peripherals

High-rate IMU via SPI/I2C
Quadrature encoders via timer inputs
Analog sensors via ADC

Comms + Networking

CAN, UART, SPI, I2C; USB device/host on some parts
RS-485 or CAN transceivers for rugged links

Real-Time + Determinism

Use DMA to reduce ISR jitter
Prioritize control tasks and bound interrupt latency

Recommended Vault Modules

EKF Localization Path Following Costmap Inflation Offline Mesh Protocol Serial Link Layer Scheduler + Watchdog Flight Data Recorder

Pitfalls + Mitigations

Clock tree misconfiguration causes timing drift
Peripheral pin conflicts due to alternate functions
DMA/IRQ priorities starving control loops

Field Checklist

Validate clock config and timer base
Confirm 3.3V logic with sensors
Set DMA/IRQ priorities for control loops
Enable watchdog and brownout reset