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Bluetooth MIDInator

I got inspired by a Youtube video on making a cool MIDI controller by Switch & Lever https://www.youtube.com/watch?v=JZ5yPdoPooU
He uses scrapped/recycled parts for the controls screwed into a beautifully crafted casing. Sadly, I'm not as talented as a craftsman as the Youtuber and could not conjure up the energy to start looting up phone dials and joysticks, yet I took on the project by building up my version.

I decided to make a Bluetooth MIDInator.  

The Arduino board I use is a Bluno board with integrated Bluetooth https://www.dfrobot.com/product-1175.html
The controller layout is a much simpler version than the original MIDInator with 16 potentiometers and four encoders.

First, I forked the repo and took a look at the code. It was understandable and readable, thus a good starting point for the project. I use a breadboard and a potentiometer to try out the MIDI communication through the serial port to a DAW with Hairless MIDI and loopMIDI, and it works pretty much out of the box.

Now came the trickiest part of the project, which was to make the wooden casing. It's made out of plywood and some wood scraps I found at my parent's farm. I drilled the holes for the potentiometers and encoders and glued up everything else but the lid.

The lid


I used copper tape on the lid as a bus for 5V and ground connector. I soldered and attached the parts close to the way as in the original MIDInator.

All wired up


Setting up the Bluetooth connection was a pain. I thought I could use a generic Bluetooth connection, but it turned out Bluno uses some proprietary protocol, and I needed to order a separate Bluetooth dongle. In hindsight, it would have been smarter to use a regular Arduino with a separate Bluetooth shield to enable the use of a universal BT dongle.

Once I received the dongle and got the connection working, all that was left to do is to modify the code to support the 16 pots and 4 step encoders. I pretty much copy-pasted stuff from the existing implementation to find out if I had any wiring problems (which I did). The coding part here was the easiest, and after a few tweaks, it was working.







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