Midibox

The MIDIbox project is an open source modular DIY framework (hardware and software) MIDI platform built around the PIC family of microcontrollers (specifically the PIC18F452, PIC16F88, PIC18F4620 and PIC18F4685) and recently with STM32FXX and LPC1769 32-bit too. It can be used to build hardware MIDI control units for various synthesizers, multi-track recording software, and other MIDI devices; as well as stand-alone synthesizers, sequencers and other projects.

The MIDIbox Hardware Platform is the continuation of Thorsten Klose's earlier work on MIDI controllers. Designs are based around a standardized environment of reusable and exchangeable modules. Soon after the release of the first modules, a small group of enthusiasts formed and grew into a thriving open source development community.

The platform focuses on well defined and documented modules based on small, uncomplicated circuits to allow for amateur assembly. These modules are then assembled into a complete project. All boards can be made as single-layer PCBs, and prototype boards designed with a freeware CAD program. Almost all components are through-hole for easier assembly.

The first MIDIbox hardware platform (MBHP) was based its own open-source operating system—MIOS (MIDIbox Operating System)—written in PIC assembly language for speed and accuracy. A C wrapper layer provides simplified coding. MIOS is designed and documented to allow simple reconfiguration, adaptation, and extension by hobbyists and enthusiasts.

The new MIDIBox Hardware Platform called MIOS32 runs on ARM-based processors LPC1769 from NXP and STM32F407 from ST Microelectronics. It is based on a Real Time Operating System (RTOS) derived from FreeRTOS. The toolchain for MIOS32 is based on GCC and uses only C language.

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