Control-Surface | Arduino library for creating MIDI controllers

Control-Surface is a C++ library typically used in Internet of Things (IoT), Arduino applications. Control-Surface has no bugs, it has no vulnerabilities, it has a Strong Copyleft License and it has medium support. You can download it from GitHub.

This library turns your Arduino-compatible board into a MIDI control surface. Just connect up some push buttons, potentiometers, LEDs ... and declare them in your code. Multiple different MIDI interfaces are supported: MIDI over USB, Serial MIDI (e.g. 5-pin DIN MIDI), Debug MIDI (prints out the messages in a readable format, and allows you to input text based messages), AppleMIDI over WiFi or Ethernet, MIDI over Bluetooth LE (experimental). For MIDI output, you can use push buttons, toggle switches, potentiometers, faders, rotary encoders, etc. All digital inputs are debounced, and all analog inputs are filtered using digital filters and hysteresis. This results in high accuracy without noise, without introducing latency. These can be used to send MIDI notes, Control Changes, Pitch Bends, Program/Patch changes, etc. For MIDI input, you can use LEDs to display the state of different settings, to display the audio level of each channel (VU meters), the positions of knobs (V-Pot LED rings), etc. You can also add an OLED display (e.g. SSD1306) to display a nice overview of which channels are set to mute or solo, display the time cursor, VU meters, etc. Bitmaps with play, mute, solo, record buttons, and others are included. A large portion of the Mackie Control Universal protocol is implemented. All controls can be arranged in banks: e.g. if you have only 4 physical volume faders, you can add them to a bank, and then you can control 8 channels (or more) by changing the bank setting. Apart from banks and bank selectors, you can also add transposers to change the key of your notes, for example. In order to save some IO pins, the library natively supports Shift Registers (e.g. 74HC595) and multiplexers (e.g. 74HC4051 or 74HC4067). If you are using a Teensy 3.x, you can use it as a USB audio interface. Just add an I²S DAC (e.g. PCM5102) and 5 lines of code, and you can start playing audio through your Teensy. You can also add volume controls and VU meters for these audio connections. Thanks to the structure of the library, you can easily add your own MIDI or display elements, using some minimal, high level code. All low level stuff is completely reusable (e.g. all MIDI operations, debouncing switches, filtering analog inputs, and so on).