Helicopters really just shouldn't fly. Ask any engineer, and they'll tell you it's a wonder that they work.

Whatever is going on with helicopters is apparently happening with this NeoTrellis I put together. Hence, the name.

These are instructions on running the Adafruit 8x8 NeoTrellis Feather M4 Kit Pack with Python:

1. First, I go through the initial setup of CIRCUITPY.
2. Then, I go through instructions to set this up as MIDI controller. This includes steps to make editing your CIRCUITPY code friendly.
3. Finally, a quick walkthrough to set this up to emulate a monome grid (i.e., an 8x8, 64-grid) for the Norns.

For development purposes, these are the steps to take with a new NeoTrellis grid, or for user-defined updates.

Bootloader. Double tap the device's reset button (pretty quick-ish) to enter "boot mode". Load (drag and drop) the most recent version of the bootloader into the disk, and let it reset to show the BOOT drive again.

CIRCUITPY. Download the most recent version of CIRCUITPY for your chip (Feather M4 Express, likely). Start the Bootloader (above), then load the UF2 file into the BOOT drive, and let it install. You'll see the CIRCUITPY drive show up when it's done.

In here, you can view the output of your code.py file. To open the console, we follow these instructions:

(One of the following should work.)

$ ls /dev*/usb*
> ls: /dev*/usb*: No such file or directory
$ ls /dev/tty*usb*
> tty.usbserial (or something like it)

Copy (to paste) the output that works, and run

screen /dev/tty.usbserial 9600,cs8,ixon

(I.e., everything in between screen and 9600 is in your copy/paste clipboard.)

To leave, press Ctrl + D. Note: you may need to press Ctrl + C to stop whatever script is happening, if you like.

This repository is meant to emulate what is loaded on the trellicopter.

I like to have my code edited in VS Code. I'll have the IDE up along with an open REPL console (above). I make updates to the trellicopter repo, which is meant to emulate what is on the Feather M4. Once I feel good about the code, I'll copy-paste the code.py file, and place it into the CIRCUITPY drive.

Step 1: Clone this repository (the main branch), and the Adafruit Blinka repo.

Step 2: Get the most recent Adafruit library for both .py and .mpy files (these will be two separate links). On my computer, I save the entirety of these in adafruit_py and adafruit_mpy folders (respectively), just to keep track.

Step 3: The folders in trellicopter/lib come from adafruit_py, so that editing in PyCharm is friendly (you can set this as a "Source" in the IDE). I'm not very diligent, so you'll probably want to replace these folders with the updated version of them in your most recent downloaded adafruit_py folder (note, these are .py files). This includes

• adafruit_bus_device
• adafruit_midi
• adafruit_neotrellis
• adafruit_seesaw

You'll need to add whatever folders are required for the project you're working on.

Step 4: The folders in trellicopter/src come from the Adafruit_Blinka repo, i.e., the most recent mirror of the Trellis firmware. Copy-paste the contents of Adafruit_Blinka/src into trellicopter/src. Again, this will make editing in PyCharm kinda nice.

Step 5: In your CIRCUITPY drive (on the NeoTrellis), copy paste the .mpy version of the folders from Step 3. So, you'll have something like:

CIRCUITPY/
    /lib
        /adafruit_bus_device
        /adafruit_midi
        /adafruit_neotrellis
        /adafruit_seesaw
    ...
    code.py

where code.py is exactly the same file as what's in trellicopter, and the folders in lib are the .mpy version of the folders from adafruit_mpy.

Step 6 - infinity: Editing. My workflow goes like this:

1. Open PyCharm, and open a REPL console.
2. Edit the trellicopter/code.py file. (For one, make sure the grid addresses match your own.)
3. Copy-paste the code.py file into the CIRCUITPY drive (the trellicopter should update).
4. Watch the output on REPL.
5. Rinse, Repeate, Smile :)

The credit for this really goes to Jeremy Arnold and miker2049.

Step 1: Clone my fork of the midigrid repository into your Norns's dust/code folder.

Step 2: Notice on line 13, I reference the (lowercase) 'feather m4 express'. After getting the MIDI set up from the above section, this title should match the name that comes up in your Norns when you plug it in.

Step 3: Also, notice that the grid notes in midigrid match the outcome of the grid calculation in trellicopter. THESE NEED TO MATCH!

Step 4: Open Maiden, and update whatever script you plan on running (except those that have built in support, e.g., Cheat Codes 2 — check the docs). At the top of the script, add include('midigrid/lib/midigrid').

Step 5: Go to PARAMETERS -> EDIT -> GRID and make sure to set the following:

• grid size = 64
• vert rotation = usb on bottom
• midigrid? = yes

Step 6: Enjoy. Have fun. Smile :)

Alternatively, you could use Steve's (okyeron's) solution:

Note: This solution only works if you have a 64-grid, 8x8, with grid addresses below:

[
    [0x2E, 0x30],
    [0x31, 0x2F]
]

If your addresses are different, reach out to Steve and follow the rest of the instructions accordingly. He is incredibly helpful!

1. Download the UF2 file (or whichever one matches your addresses), and install it onto your system using the bootloader.
2. Access your norns via WiFi using SSH.
3. Complete this fairly benign Norns hack, here (roughly, to allow Norns to recognize this device's serial number). This needs to be done after every Norns Update.
4. Restart your Norns.
5. Make sure that you've uninstalled midigrid in maiden (if you don't need it anymore), and that you've removed references to 'feather m4 express' as a MIDI controller. MAIN -> SYSTEM -> DEVICES -> MIDI -> select-and-change-to-"none".
6. Also, make sure that your Norns is seeking out the right grid: MAIN -> SYSTEM -> DEVICES -> GRID -> select-and-change-to-"neo-monome m4216124".
7. (optional) If you're running something like Cheat Codes 2, you'll need to update the grid parameters there, and make sure midigrid? = no: PARAMS -> GRID -> midigrid? = no.
8. Do music.

• Keycodes