automat firmware

Firmware for the dadamachines automat MIDI-to-solenoid controller.

Built with PlatformIO using the Adafruit Arduino SAMD Core.

Hardware

• MCU: SAMD21G18A (Cortex-M0+, 48 MHz)
• 256 KB Flash / 32 KB RAM
• 12 solenoid outputs via SPI shift registers
• USB MIDI + DIN MIDI input
• UF2 bootloader for drag-and-drop firmware updates

USB Power & iOS Compatibility

The firmware declares a USB bus-current draw of 100 mA (Adafruit SAMD core default). The original dadamachines BSP declared 20 mA. Both values are well within the USB 2.0 limit of 500 mA, so the automat enumerates normally on iPads and other iOS devices. Solenoid power is supplied externally and is not drawn from USB.

Configuration

Use the automat configurator (WebMIDI) to set per-output velocity programs, min/max timing, and gate durations. Source: dadamachines/automat-configurator

Build

Prerequisites

• PlatformIO CLI or PlatformIO IDE (VS Code extension)

Compile

pio run

After a successful build the firmware files are in .pio/build/automat/:

• firmware.bin — raw binary
• automat-sw_<version>.automat.uf2 — UF2 file for drag-and-drop flashing

Upload via SAM-BA (serial)

pio run -t upload

Flash via UF2

1. Double-tap the reset button on the automat to enter the UF2 bootloader.
2. A USB drive named AUTOMAT will appear.
3. Drag automat-sw_<version>.automat.uf2 onto that drive.
4. The board resets automatically and runs the new firmware.

Note: UF2 flashing requires the dadamachines UF2 bootloader. If your automat still has the original SAM-BA-only bootloader, use pio run -t upload instead, or flash the UF2 bootloader once via SWD/JTAG.

Dependencies

Managed automatically by PlatformIO (declared in platformio.ini):

Library	Source
FlashStorage	cmaglie/FlashStorage
Arduino MIDI Library	FortySevenEffects/arduino_midi_library
MIDIUSB	arduino-libraries/MIDIUSB
OneButton	mathertel/OneButton

Project Structure

├── platformio.ini              # PlatformIO build configuration
├── boards/
│   └── dadamachines_automat.json   # Custom board definition
├── variants/
│   └── automat/
│       ├── variant.h           # Pin mapping
│       └── variant.cpp         # Pin descriptions
├── src/
│   ├── main.cpp                # Main firmware
│   ├── automatConstants.h      # Board constants
│   ├── solenoidSPI.*           # Shift-register solenoid driver
│   ├── dadaMidiLearn.h         # MIDI learn mode
│   ├── dadaStatusLED.h         # Status LED controller
│   └── dadaSysEx.*             # SysEx configuration protocol
└── extra_scripts/
    └── post_build_uf2.py       # Automatic .bin → .uf2 conversion

Change log

• V3.11 — Remove all PWM/motor code and files (PWMManager, humTiming); remove pitch bend and mod wheel handlers; clean up unused constants
• V3.10 — Simplify velocity programs: only Default (velocity-mapped timing) and NoteOn/NoteOff (always-on) remain active; SysEx/WebUI compatibility preserved
• V3.02 — Fix I2C message validation, pin bounds checks, PWMManager array bug
• V3.01 — Version bump, named UF2 output, README updates
• V3.00 — PlatformIO migration, Adafruit SAMD core, UF2 output
• V1.10 2018.04.15 — Velocity support added
• V1.00 2017.10.19 — Initial release

Related Repositories

• dadamachines/automat-configurator — WebMIDI configurator for velocity/gate settings
• dadamachines/uf2-samdx1 — UF2 bootloader (fork of microsoft/uf2-samdx1)
• dadamachines/arduino-board-index — Legacy Arduino Board Support Package (superseded by this PlatformIO project)

Contact

To report a bug, contribute, discuss on usage, or simply request support, please create an issue here or reach out via dadamachines.com/contact.

License

GPLv3 Copyright © 2014-2026, Johannes Elias Lohbihler for dadamachines