Morse-It

MIDI Hardware interface Sample

In Morse-it, it is possible to use a MIDI device as Morse input.
By default,

for iAmbic Keys : the note number 18 is associated to the dit, and the note 38 to the dah.
for Straight Keys : the note number 18 is associated to key.

Here is a cheap and easy way to create such an adapter for your own Morse key.

You'll need :

an Adafruit Trinket M0
for recent iOS devices: a micro usb to usb cable
for older iOS devices: a micro usb to usb cable and an usb to lightning adapter
if necessary : an audio jack to connect your Key to the microcontroller.

Here is a photo of my configuration:

In this configuration, the Morse key is connected to the ground and to the I/O pins 3 and 4.

I'm using the librairies adafruit_midi (only a subset of it is necessary), adafruit_debouncer, adafruit_ticks.
The following code has been tested with CircuitPython 9.1.1, so you might have to upgrade your circuitpython version (as explained here).

There are 2 specific python files to make this work :

code.py (the main code including a debouncer):


import usb_midi
import adafruit_midi
import board
import digitalio

from adafruit_debouncer import Debouncer
from adafruit_midi.note_on import NoteOn
from adafruit_midi.note_off import NoteOff

midi = adafruit_midi.MIDI(midi_out=usb_midi.ports[1], out_channel=0)

# Define the pins
pin_left = digitalio.DigitalInOut(board.A3)
pin_left.direction = digitalio.Direction.INPUT
pin_left.pull = digitalio.Pull.UP
switch_left = Debouncer(pin_left)


pin_right = digitalio.DigitalInOut(board.A4)
pin_right.direction = digitalio.Direction.INPUT
pin_right.pull = digitalio.Pull.UP
switch_right = Debouncer(pin_right)

while True:
    switch_left.update()
    switch_right.update()

    if switch_left.fell:
        midi.send(NoteOn(18, 120))
    if switch_left.rose:
        midi.send(NoteOff(18, 120))
    if switch_right.fell:
        midi.send(NoteOn(38, 120))
    if switch_right.rose:
        midi.send(NoteOff(38, 120))

boot.py (the code necessary to disable the keyboard feature):
```
import usb_hid
usb_hid.disable()
		
```

Click here, to directly download an archive with the needed librairies and those 2 python files.
Unarchive the downloaded file, and put all the unarchived content directly on the disk of your Trinket MO:
(Move/Replace the code.py, boot.py files and lib folder to the root directory of the CIRCUITPI drive).

That's all!
you can now use Morse-it with your external key.