Mazduino ECU Custom Firmware

Custom rusEFI firmware for Mazduino ECU boards and compatible STM32F4-based engine management systems.

Download

Pre-built firmware is published as nightly releases on the Releases page.

Each release includes .bin, .srec, and .hex files for every supported board.

Supported Boards

Mazduino Compact

• MCU: STM32F407VGT6 (1MB flash)
• Hardware knock detection via ADC3/PA3
• Software knock spectrogram
• CAN bus, USB virtual COM port (TunerStudio)
• Dual idle solenoid outputs
• No ETB, no traction control

Mazduino Lite

• MCU: STM32F407VGT6 (1MB flash)
• No hardware knock (ADC3 not connected)
• CAN bus, USB virtual COM port
• Dual idle solenoid outputs
• No ETB, no traction control

Mazduino Mini 6CH (STM32F427VGT6)

• MCU: STM32F427VGT6 (1MB flash)
• Electronic throttle body (ETB) support
• Traction control (requires ETB)
• Hardware knock detection
• CAN bus, USB virtual COM port

Mazduino Mega100 (STM32F407VGT6)

• MCU: STM32F407VGT6 (1MB flash)
• Full feature set: ETB, traction control, knock, boost, launch control
• Dual pinout support: board04 layout and UA4C layout, switchable via TunerStudio board action
• USB virtual COM port and CAN bus for TunerStudio connection
• Status LED at PB7

Mazduino Mega100-512 (STM32F407VET6)

• MCU: STM32F407VET6 (512KB flash)
• Firmware constrained to 384KB to preserve tune storage sector
• Feature reduction vs Mega100: no ETB, no knock, no boost control, no launch control, no Lua, no SD card
• CAN bus or USB virtual COM port for TunerStudio connection
• Status LED at PB7

TunerStudio Connection

Board	Connection
Compact, Lite, Mini 6CH	USB virtual COM port
Mega100	USB virtual COM port or CAN bus
Mega100-512	USB virtual COM port or CAN bus

Building Firmware

Local Build (Docker)

Docker is required. The build image uses Ubuntu Mantic with ARM GCC toolchain.

# Build all boards
./build_boards.sh

# Build a single board
./build_boards.sh mazduino-compact

The script uses --platform linux/amd64 to ensure hex2dfu.bin (x86-64) runs correctly on Apple Silicon via Rosetta 2.

CI Build (GitHub Actions)

All boards are built automatically on every push via the matrix workflow in .github/workflows/build-matrix.yaml. Nightly releases are published by .github/workflows/nightly-release.yaml.

Flash Instructions

ST-Link or SWD

Use STM32CubeProgrammer or OpenOCD with the .bin file:

st-flash write rusefi_mazduino-compact.bin 0x08000000

DFU (USB bootloader)

Put the board into DFU mode (hold BOOT0 while resetting), then:

dfu-util -d 0483:df11 -a 0 -s 0x08000000:leave -D rusefi_mazduino-compact.bin

OpenBLT Bootloader

Use the .srec file with the rusEFI Flasher tool or BootCommander.

Repository Structure

boards/
  mazduino-compact/       # Board-specific configuration files
  mazduino-lite/
  mazduino-mini6ch/
  mazduino-mega100/
  mazduino-mega100-512/
ext/rusefi/               # rusEFI submodule
generated/                # Auto-generated code (configs, headers, INI files)
.github/workflows/        # CI/CD workflows

Each board directory contains:

• meta-info.env - Board identity and CPU selection
• board.mk - Makefile flags and feature overrides
• board_configuration.cpp - Pin assignments and hardware init
• efifeatures.h (optional) - Feature flag overrides
• prepend.txt - TunerStudio UI visibility flags
• knock_config.h - Knock sensor configuration

Safety Notice

This is engine management software controlling critical engine functions. Test on a bench setup before installing in a vehicle. Incorrect configuration can cause engine damage.

Links

• rusEFI Project
• rusEFI Custom Firmware Guide
• Mazduino Wiki