[Bjonnh.net]# _

On using 3d printer screens and controllers for your own projects.

I bought some of those cheap 3d printer controllers on the big evil site for $12: BigTreeTech Mini 12864. There are other similar ones in the same price range from other brands, but I can’t guarantee they have the same pinouts and controllers. Also these came with a tiny yellow rubber duck, always useful when you try to make sense of schematics.

The LCD running displaying a menu

The thing is, these are made for 3d printers so they expect you to plug them directly and not worry about implementation details.

Fun thing is, for some printer models, you need to make an adapter cable as nobody seemed to have settled on a standard for those and pinouts are all over the place.

To save you from the hassle of figuring out how to use those with an Arduino or an ESP, and likely for me later when I will need that again, I decided to write down all I discovered about them.

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categories electronics hack tags arduino electronics midi

Finally, I am trying to reorganize this website, add a portfolio and other kind of stuff that will help me remember the ton of stuff I wrote but never talked about. I’ll document in this article the different kind of things I tried. I am especially excited by the portfolio aspect (of which most will be private though).

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category personal tags hugo website

A circular slide-ruler
We had this conference in Chicago in 2016. As I was playing with the laser-cutter and making planetary motion devices see Here, I also was playing with the idea of circular slide rulers. As the calculation of elution volumes and retention in CCC and CPC are using multiplications and divisions it is possible to do these on a circular slide ruler (or a normal one) by using logarithmic scales (because additions in that space correspond to multiplications in linear scale).
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categories science hack tags ccc cpc conference laser-cutter laser

Someone toying with a laser-cut award
We had [this conference](https://gfp.people.uic.edu/ccc2016/) in Chicago in 2016. As I was playing with the laser-cutter and making planetary motion devices, Guido asked if it wouldn't be possible to make two awards for the conference. I also made a [Slide ruler](/article/20170530_cccslider) for that conference. A bit of design, metallic-gold acrylic, flexible metallic with black background acrylic for the tag, and a piece of wood made by a colleague (Jim). I also found that simple M3 or M4 (can’t remember) screws with thin thread will lock perfectly two pieces of acrylic (with a hole cut slightly below the diameter of the screw).
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categories science hack tags ccc cpc conference laser-cutter laser

A cat that has been transformed
This article is in english, but the original one is in french. Just because many english-speaking people asked me about these transforms. (Cet article est en anglais, même si l’original est en français. C’est juste parceque on m’a plus souvent demandé en anglais qu’en français plus d’informations sur ce sujet. Mais ça devrait être plutôt clair pour les francophones.) Through my migration to o-blog v2.5 I found some old experiments I did with FFT related to this Rapport d’écoute - Sur les épaules de Darwin (France Inter) - La forme des mots
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category science tags rapport son perception

I use Notmuch to manage my emails (and that’s just wonderfully fast) and use the Emacs frontend for it. But when I wanted to save attachements, it was not that easy to create folders. I had to exit the save, open a terminal, a dired or whatever create the folder… I use Helm for managing completion in emacs (and that’s a nice piece of software too).

To avoid that and with the help of Sacha Chua, I managed to add a shortcut in helm read file:

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category computer tags emacs helm notmuch

A cat that has been transformed

Suite à l’émission de France Inter « Sur les épaules de Darwin, La forme des mots », j’ai décidé d’expérimenter un peu avec la conversion d’images en sons par transformée inverse de fourier.

Pour cela, j’ai utilisé le logiciel ARSS, un peu vieillot, mais qui fait ce qu’il a à faire.

Commençons par un petit exemple, transformons l’image de la formule de cette fameuse transformée en son avec la commande :

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category science tags rapport son perception