DARTMOBO

The DART_MOBO is the core of the DART ecosystem: an Arduino shield designed to build MIDI, DMX and HID controllers of all kinds.
It offers 48 configurable inputs (expandable to 56), support for 32 LEDs, high-resolution spinners, touch sensors, and a modular expansion system based on DART_CONTROLBOARD modules.
The board can be equipped with MIDI and DMX interfaces, while native USB MIDI support is available on Leonardo-based systems immediately after uploading the sketch.
DART_MOBO is compatible with Arduino Uno, Leonardo, and the more powerful Adafruit Metro M0 Express, which provides additional memory and processing power for advanced projects.

 

INPUT / OUTPUT numbering:

The diagram below shows the input and output pin layout of the DART_MOBO board.

The blue pins (1–48) are the standard inputs used to connect a wide range of controls, including digital devices such as push buttons and analog devices such as potentiometers, faders, and sensors.

The green pins are digital outputs, typically used to drive LEDs and generate visual feedback, but they can also be employed to control other types of external devices.

The purple pins represent 8 additional inputs, extending the total number of available inputs from 48 to 56. These extra inputs are accessed through the Extraplex feature, which is described in detail on its dedicated documentation page.

 

Beyond providing a large number of configurable inputs and outputs, the DART_MOBO PCB also includes several onboard utility circuits that can simplify the construction of advanced MIDI controllers.

Among the integrated features are:

  • MIDI IN and MIDI OUT circuitry for standard DIN connectors, still widely used in music production and studio environments.
  • DMX output circuitry, allowing DART-based controllers to operate as lighting consoles, including support for scene recording and recall functions.
  • Touch sensing support, which can be implemented either through a lightweight internal solution requiring only a few passive components, or through external dedicated hardware.
  • Lighting support circuits designed for backlit controls, illuminated panels, and other visual feedback systems, with optional brightness and fade effects.

These features are entirely optional and can be added only when required. The core purpose of DART_MOBO remains the management of generic controller inputs, while the additional circuits provide convenient building blocks for users who wish to extend their projects with MIDI, DMX, touch sensing, or advanced lighting functions.

Detailed guides are available for all optional circuits, allowing builders to decide which features to include according to the needs of their project.

SOLDER PADS

All input and output pins, as well as the main board connectors, provide not only the usual through-holes for pin headers and IDC connectors, but also generous solder pads for users who prefer to wire their actuators directly to the PCB.

Many makers favor this approach during prototyping, using simple pre-tinned hookup wires available in a wide range of gauges (AWG sizes) and lengths. While somewhat quick-and-dirty compared to connector-based solutions, direct soldering remains a fast, practical, and highly effective way to build prototypes and experiment with new controller designs.

PORTS

We use the term ports even for simple groups of input/output pins, since their layout allows them to be used either individually or as grouped connections through IDC headers and flat cables, giving the end user maximum flexibility.

Many of these connectors also include convenient +5V and GND pins, making it easy to add dedicated modules for buttons, potentiometers, or encoders. This approach is particularly useful for our semi-modular preassembled controllers, but it is equally valuable for users who wish to design their own DIY expansion modules.

In addition to these grouped connectors (J1–J10), the DARTmobo provides dedicated ports for MIDI over DIN, DMX communication, Spinner connections and so on… (see the port legend below for details).

  • J1 -J6 – Input ports used to connect to Potboard and Buttonboard.
  • J7-j10 – Output ports, used to connect to Buttonboards.
  • J11-J12 – MIDI IN/OUT over DIN.
  • J14 – DMX output.
  • J15 – Main spinner.
  • J16 – combo connector to NB-Controlboards.
  • J18 – Side spinner.
  • J19 – control signals to the shifters for led output.
  • T1-T2 – Pads  for touch sensors.

Getting Started with DARTmobo

You’ve got a DARTmobo PCB on your desk. Nice. Now let’s make it do something.

The DARTmobo is basically a giant Arduino shield. Plug the Arduino into the board, connect it to your computer, and upload the standard DART sketch.

No coding is required at this stage. The default sketch already includes an autodetect system capable of recognizing buttons and potentiometers and converting their activity into MIDI messages.

This means you can start experimenting almost immediately. Once everything is working, you can move on to the DART Editor and create a custom, stable preset that matches your controller design.

At this point, we recommend checking out the Pots & Buttons guide, where you’ll find everything you need to know about the basic setup and configuration.

Editor view

The DART Editor’s main screen mirrors the input layout of the DARTmobo. Selecting an item opens its full configuration panel. Once your hardware is connected, you can freely reposition the items to match the front panel layout of your controller rather than the PCB itself.

 

DARTMOBO on a breadboard

We are showing the core DARTmobo circuit here in its simplest breadboard form. It is built around widely available 74HC4051 multiplexers and 74HC595 shift registers, reflecting our goal of creating a platform that is easy to understand, modify, repair, and reproduce using inexpensive, easy-to-find components.