MIDI controller and sequencer

 In this post I'll document the making of my DIY MIDI controller


CONCEPT

The controller is based on a STM32f1 microcontroller that polls a daisy chain of SN74HC165 shift registers. Each register bit is connected to a keyboard key (taken from a broken keyboard) to a total of 24 keys or two octaves.

At the panel there are controls for inhibiting the transmission of the MIDI signal, inhibiting the transmission of the analog signal, selecting the note range of the keyboard, start/stop the sequence, setting the speed of the sequence and recording notes to the sequencer.

The panel also contains the connector for 12V DC.

The case for the controller was made with a one centimeter thick plywood sheet, cut and glued into place.

The keyboard was fixed with screws from underneath that thread through a plywood block before reaching the keyboard. This raises the keyboard up and prevents the keys from hitting against the base.

CONSTRUCTION

Glueing the plywood parts for the case


The panel and board assembly



Still a work in progress but this is the full assembly so far.


CODE

The code was done in arduino and it can be found at my github: github

SOUND SAMPLES

Video

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