MIDI Controller

A MIDI controller designed specifically to suit my music producing approach.

After a deep search on the internet trying to find the perfect MIDI controller for my needs, I got disillusioned with the results since, either they were not meeting my requirements at all, or they were incredibly expensive. Then I was left with one only possible solution: designing and building my own.

The goal of this project is to develop a MIDI controller fitted with the features I really find valuable when producing music on the laptop. It consists of a set of potentiometers connected to Arudino microcontroller, all enclosed in a wooden handmade case.

1. General description

This device consists of an Arduino Pro Micro with a series of potentiometers connected to it. The electronics will be protected by a walnut wooden case. It is powered by directly by the 5V USB port from the laptop, which eliminates the need of adding batteries. It is operated by acting directly on the potentiometer knobs, that will consist of 2 fader, and 2 rotating ones.

2. Arduino Pro Micro

2.1 Description

The Arduino Pro Micro is a micro controller board designed by Arduino. Due to its reduced size and native MIDI protocol connection, it is ideal to be utilised on this project. It possesses 12 analog inputs, which allows to connect the required potentiometers used. The programming language to be implemented is based on C++, but it is simplified by the availability of ready to use libraries accessed by the Arduino IDE.

2.2 .....

3. Electronics setup

3.1 Working principle

In basic, the potentiometers, which are a variable resistor, provide a certain voltage into one of the controller's inputs. This input is then processed by the Arduino according to the code that has been flashed on the chip, and then sends the output as MIDI data, so the laptop can interpret it.

In order to understand the functioning of the device, a simple schematic is presented below:

Figure 3.1-1 Voltage booster schematic

The n-moset transistor M1 acts as a switch in this circuit, crating to different stages that make the boosting of the voltage possible. For doing this, the MOSFET opens and closes depending on the pulses generated by the 555 timer, which is connected to its trigger leg. Therefore, the stges are:

Next step is to include in 555 timer circuit in the schematic. See figure below:

3.2 General Component list

The main components that are used in the radiation detector are shown below:

2 10kOhm Potentiometers (Sliders)
1 10kOhm Potentiometer (Rotational)
Arduino Micro Controller
Cables
Wooden case

4. Assembly and soldering

4.1 Putting all together

After soldering all components together, the circuit looks as follows: