abw/midi-patchbay

Hardware and firmware for a 4x4 MIDI merger/splitter patchbay based on an Arduino MEGA 2560

MIDI-Patchbay

This project contains hardware and firmware for a 4x4 MIDI merger/splitter patchbay based on an Arduino MEGA 2560. It has 4 MIDI inputs and 4 MIDI outputs. In the simplest case, it will merge all 4 inputs and then split the combined MIDI stream across the 4 outputs. However the routing is controlled by the firmware so you can configure it to patch any combination of inputs into any of the outputs.

Table of contents

• Hardware
• Firmware
• Warning

Hardware:

The hardware directory contains Eagle schematics, board designs and Gerber files for the following modules.

• MIDI-Patchbay-Shield is a shield for an Arduino MEGA 2560 that provides 4 MIDI inputs, 4 MIDI outputs and connectors for interfacing to the MIDI-Patchbay-Display board. It also contains connectors for accessing 8 analog pins and 8 digital pins for further expansion. This is the main board that you need to build.

• MIDI-Patchbay-Display is a board for mounting a 16x2 LCD display and two RGB rotary encoders. This is an optional extra. You can build a fully functioning MIDI merger/splitter without it.

• MIDI-Patchbay-Simple is the predecessor of the MIDI-Patchbay-Shield. This is a reduced size shield for the Arduino MEGA 2560 that only has 4 MIDI inputs and 4 MIDI outputs, along with the relevant circuitry to support it. If you just want a simple MIDI merger/splitter without any extra frills then this is the simplest option as an alternative to the above.

The boards use surface mount (SMD) components, but nothing smaller than 0805 (that's 2012 in metric: approximately 2.0mm x 1.25mm) which can easily be soldered by hand. It's really not much harder than through-hole components, so don't be put off if you haven't used SMD before. But you will need to invest in some tweezers and a magnifier/light unit to help you see what you're doing. And of course, a decent soldering iron.

Firmware:

The firmware directory contains the source code for the firmware that powers the boards listed above. It is built around the Arduino MIDI Library by Forty Seven Effects.

• MIDI-Patchbay-Simple.ino implements a simple 4x4 MIDI patchbay that merges all four MIDI inputs and duplicates them across all four MIDI outputs. It is specifically for use with the basic MIDI-Patchbay-Simple board, but can also be used with the more advanced MIDI-Patchbay-Shield if you just need simple functionality. Or you can use this as a starting point for your own implementation of the firmware.

Warning:

These are new designs that haven't been fully tested yet. Use them at your own risk.

Author

Andy Wardley [email protected] December 2017

midi-patchbay's Issues

MIDI-Patchbay-Shield.sch - conldn't be opened using KiCAD

What tool is needed to open the *.sch files?
Couldn't open it using KiCad...

MIDI-Patchbay.h is blank

Opened the ino file to preview the firmware before building, Much to my chagrin, found several errors when verifying the firmware, mainly dealing with midiA, midiB, midiC, and midiD. Looked through the included files and found that MIDI-Patchbay.h is blank, with only the following in the file:

../MIDI-Patchbay.h

I don't know if this was intentional or not, as I am new to programming, especially programming Arduinos. Is there any way you can help with this? Thank you.

Schematics poor quality...PDF available?

Where does the rotary pinheader belong to on my Arduino?

Where does the digital pinheader belong to?

Could you upload the schematics with better font as filetype PDF (so we can copy/paste text we couldn't read)?

BOM - Bill of Material

Hi, I wonder if there's a BOM. Especially for the 1K@100MHz conductors I'd like some more info.... Why do we need this? What parts did you use for them?

Compatibility PCF8574?

Hi,
which files would I need to configure to get an HD44780 running on i2c?

Also a new layout for Arduino2560 Pro mini would be nice, since we don't need so much space for the Arduino board ;)