Battery powered Zynthian with build in keyboard


What do you think is best way to make Teensy and Raspberry pi to talk to each other? I was thinking about making Teensy into MIDI controller.


Mine runs on battery power… Via power bank


That is probably easiest way to do it but I have not found power bank that you can recharge and use as power supply at same time.


MIDI won’t be enough. OSC as well f.e.
This is something, jofemodo should decide.
I guess zyncoder (part of zynthian) will handle it.


How come MIDI is not enough? Shouldnt it work with MIDI keyboards?


i can imagine that it’s best to design your own protocol. zyncoder maps to midi then.
But i don’t have the overall picture here.


What kind of protocol are you talking about? I am new to computer programming. Do you mean some kind of communication protocol between Teensy and Pi?


I have ordered everything except rotary encoders, PCBs I designed and maybe some other thing but I lost the list of things I did not order. I dont have money to buy encoders now as they are over 60€. I will check what I ordered when things arive. Rotary encoders will be ordered during this month as is PCBs I designed.


Eiiin?? What kind of encoders do you intend to use? Normal PEC11R-xxx encoders shouldn’t cost more than 2-3 euros/unit.




I have some of them for a MIDI controller project. We made transparent knobs with a 3D printer…


OK! I forgot you want to use these encoders :wink:



What kind of filament you used? I also have 3d printer.


Uhhhh - I don’t know where the filament is from… I have no own 3D printer, but a good friend who is willing to print my ideas.

Here they are… If you need the STL data, I can go and search for it :wink:

Regards, Holger


It seems a standard PLA transparent filament. I use it when I need light transmission, like in the buttons I made for the Pocket Operator:


Does stl files happen to be made so that size of knobs is easily changed?

I have ordered RBG led rotary encoders. :slight_smile: Thanks goes to tax refunds. I think I will buy few eurorack module PCBs.


Hm, maybe… I made the STl and a friend took it and “pimped” it up. I will try to find the file in my archive and upload it here.

Regards, Holger


Just fiddle with OpenScad and one of the many customizable knobs, or create your own, it’s a nice exercise for you programming skills or for your cursing ones… YMMV :wink:


One more option for creating a low profile version.

The Raspberry Pi Compute Module 3

Intended for embedded industrial applications, the 67.6mm x 31mm board seems to bring out all the normal Pi functionality, and some additional processor pins to a DDR2 SODIMM socket, except USB and WiFi/Bluetooth which you my have to recreate. It lists for $35 US, perhaps you can get by without the expensive developer parent board professionals would use.

You (and your crew?) also would have additional work replacing the 40 pin GPIO connections for Audio and Display boards (not needed anyway if adapting lower cost generic Chinese boards like this $3.77 I2S PCM5102A DAC)


That would be one option but I have received raspberry pi 3 already.

Sorry for time off from this project I am easily distracted and got distracted by ukulele, modular synths and physics of mechanical flying device that flies by flapping its wings. I got pretty good at playing ukulele and learned lot of synths but was not able to calculate forces I wanted to because of lack of calculus skills. I will post link to that physics problem when I post it to some physics forum if anyone of you is interested in it.

I think here is everything that I need to build my Zynthian except, force sensors, wood, face plate, Zynthian PCBs and RGB rotary encoders. Oh and keyboard and few connectors are missing too. I forgot to include them in picture.

Rest of this week will be spend prototyping rotary encoder part of pcb so that I know do I need to use external pull up resisors or can I use teensy’s internal resistors. After I get answer and have done modifications if there needs to be some, I will send files to PCB manufacturer.