M
markh

  • Dec 12, 2023
  • Joined Apr 30, 2020
  • 5 discussions
  • 33 posts
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    took some finetuning, but finally got that OLED up and running!
    ended up rewriting a big chunk of my main pd patch to make them play together nicely.
    i got 'bad host' errors galore, trying to send data from _main.pd to the service file in the background.
    found out the latter only opens OSC communication about 7 seconds after _main.pd starts ⚠
    and reading files from the SD card was also a problem while the service was starting up.. had to put in a number of [delay]objects in strategic locations to make the whole thing start up as it should.

    when i power up, my whole startup procedure now takes about 22 seconds. not great, but could be worse.
    once it's running, it's absolutely fine, so no complaints.
    the woodwork could also be a bit sharper 🙂 but hey, prototyping is the name of the game.
    happy camper!

  • Looper with random slicing and layers patch. Foot controller just plugged in to usb on the bela mini and worked (set to midi values in patch).

  • Wanting to use Bela Mini as a mini effects unit to run different patches. I needed a screen as using knobs for different purposes on different patches and switch is so I can use 4 knobs for 8 things.

    Really impressed with this little thing, the easy IDE and documentation in forum on getting the screen going. Will start to learn more now I have a working "module". I think the case might need an upgrade though!

  • Hi Lokki,

    Great that you are getting around to experimenting with the Trill sensors. Using two Trill crafts to make a complex interface with 60 channels will work a treat. Here's a photo of an instrument I built using two Trill Crafts and pieces of brass. Each brass piece acts as a capacitive sensor with a variable reading.

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    You get a variable reading for each sensor channel so yes you can read something which is approximately equatable to pressure although as Giulio mentioned it is more a reading of how much contact is made with the capacitive surface rather a reading of the pressure applied.

    In terms of sensing the direction of finger movement you will need to think about the best layout for this and interpolate between multiple channels. If you have a look at the other Trill touch sensors you will see the kind of layouts we have used to make sure that a fingertip is always touching more than one capacitive pads at once (the zigzag shapes on the sensor surface). This allows us to calculate the position of the fingertip. You can definitely achieve similar effects with two or more pads close to each other or interlocked together. It's a lot of fun to experiment with as geometry plays a huge role in deciding the effectiveness of the sensing.

    Similar topics are touched upon in this tutorial, particularly the section about design your own slider with Trill Craft: https://learn.bela.io/tutorials/trill-sensors/working-with-trill-craft/

    • While you can program the Trill sensors with C, a popular language is Python, so I have written a very unofficial library that reads the Trill sensors from Python. This is in the MagPi magazine out today, available in newsagents, or on line, or free PDF download.
      There is a video of it in action at

      Code at:-
      https://github.com/Grumpy-Mike/Mikes-Pi-Bakery/tree/master/Trill%20Part%201

      Magazine at:-
      https://magpi.raspberrypi.org/issues/102

      Enjoy.
      Next month at this time three projects using Trill sensors.

      • I'll add to the mix of suggestions something that simplifies this for me.
        Adafruit LCD USB backpack:
        https://www.adafruit.com/product/782

        Then power comes from your BBB USB port and it shows up as a USB TTY device, which should be really easy to use from Pd (I'm talking to it using C++ directly).

        Some extra advice on this USB backpack is the code shipped from Adafruit is a little bit buggy (weird stuff happening with read/write EEPROM), so custom characters and saved stuff get garbled and mixed up sometimes.

        The github user CanyonCasa fixed the bugs and added some nice features (GPIO):
        https://github.com/CanyonCasa/BackpackPlus
        I forked this and added an audio level meter and some other small things that strike my fancy:
        https://github.com/transmogrifox/Adafruit_USB_Backpack_Plus
        Also I added the .hex file for the EEPROM clearing utility, so hypothetically all you need is AVRdude and the instructions on my github to flash this image if you want to.

        The image from Adafruit works mostly ok, so there are only some odd behaviors you will notice when you try to do stuff with custom characters or RGB backlighting saved settings.