Author Topic: I have a working MIDI project using Digispark - I need advice before sharing  (Read 9726 times)


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Greetings to all,

Off the top, I have to mention that I'm totally new to any kind of microcontroller development.

I bought into the Digispark partially because of the low cost, but also because of the tiny footprint. I have several project ideas around using MIDI to extend the features of my musical equipment so i bought the 5-pack and set about making my first project.

It's been a fairly steep learning curve, especially when it came to adding a working MIDI implementation to my first sketch, given the absense of specific information on this for the Digispark.

But now it's done and working, and I'd like to share so that others can have an easier time getting up that curve.

What I have is a working circuit and sketch that supports 2 footswitch inputs and MIDI output.

I have fully prototyped the circuit design, which includes an inverter chip for buffering the MIDI output, and have created a veroboard layout

for a shield where all of the electronics are on a single piece of board, with headers for attaching the switches and the MIDI 5-pin DIN port.

The headers are being recycled from an old motherboard - a personal goal was to keep this as low-cost as possible.

I intend to share the whole thing as a complete project document. This will include:
- veroboard layout showing all components, connections and line-cuts
- pics of the shield build - this is in progress but will be done soon
- the code for the sketch.

So here's what I need before I share the project:

1 What copyright can/should I claim on what i share?
- I have no issues with folk using it freely, I'd just like to suggest that i get a little credit :)
- do i share the shield design and the code of the sketch using the same copyright or are there different standards.
- My problem with this is time - I would probably waste a lot of time trying to find the best practice on this so I'm hoping someone on here can just point me at what i need. Thanks.

2 I would like a volunteer and/or advice to assist in bringing the code up to date with the latest dev environment
- I'm still using the 1.04 version from the download
- I used the sample single-pin serial example code that was in this download to get the MIDI working
- I tried a newer version of the IDE but my sketch wouldn't compile and I didn't have the patience to figure it out.
- In the absense of help here, I WILL still post the project in the projects forum, but it will have out of date code. It's that time thing again.

3 Getting the MIDI output working involved finding and fixing a bug in the serial libraries related to the MIDI baud rate timings.
- This may be fixed in the latest libraries, but in case it's not I probably also need a pointer to where i submit the bug report to.

All help and advice is welcomed and appreciated,


  • Sr. Member
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I don't know if there were any relevant library improvements in newer versions, or why you had trouble compiling with a newer version of the IDE. But I do recommend trying to get it working with newer versions -- 1.6.7 is current, I recall 1.6.6 had some bugs, but I've been using 1.6.5.

As for licensing, maybe look at the CERN Open Hardware License? It's patterned after the GPL, and so requires derivative works to retain the original copyright credits. On the software side, I tend to use the MIT license, as it's GPL-compatible, and even less restrictive. There are other hardware licenses out there, but CERN OHL is the only one I can think of at the moment.

Please do share more details! I'm sure there are plenty of people who might be interested.

And lastly, have you seen this project? World's Smallest MIDI Synthesizer

Be sure to check out the link to his Synthesizer Cable, which has more build details and sofware (ATTiny assembly), and the other projects, as well!


  • Newbie
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And lastly, have you seen this project? World's Smallest MIDI Synthesizer

That's cute.

Thanks for the info. I'll look into it.


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I have tried with that idea with more or less dead ends but the Idea could be done a Similar way as mitxela did it, where you just delete the existing Bootloader and put the same program that he did, and maybe even add an ability to make the Attiny85 both display the midi thru the USB but also make it play out a little speaker or make it display the note you are on with a text display of some sort, but this is just me blabing about stuff that i think you might not want to hear
« Last Edit: August 14, 2018, 01:09:03 am by Teleputer »