Rust Morse Trainer

A Morse code decoder written in Rust. Supports two input modes: a physical button via GPIO (embedded board) or the spacebar on a standard Linux keyboard.

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Install dependencies

sudo apt-get install build-essential
sudo apt-get install libc6-dev-riscv64-cross
sudo apt-get install gcc-riscv64-linux-gnu

Note

For keyboard mode, make sure your user is in the input group so you can read /dev/input/event* without root:

sudo usermod -aG input $USER
# Log out and back in for the change to take effect

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Build

Keyboard mode (standard Linux PC)

cargo build --release --features keyboard

GPIO mode (embedded board)

cargo build --release --features gpio

Both modes available in the same binary

cargo build --release --features gpio,keyboard

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Run

Keyboard mode — hold SPACE to transmit, release 2 s to decode

./target/release/morse --input keyboard

GPIO mode — physical button on the board

./target/release/morse --input gpio

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How it works

Hold the button/key for a short time to send a dot ·, hold longer for a dash —. The decoder calculates the dot/dash threshold automatically from your own rhythm, so no manual calibration is needed.

Signal	Duration
Dot	1 unit
Dash	3 units
Gap between symbols	1 unit
Gap between letters	3 units
Gap between words	7 units

After 2 seconds of silence the current sequence is decoded and printed.

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Logging

Set the RUST_LOG environment variable to control verbosity:

RUST_LOG=debug ./target/release/morse --input keyboard   # show every pulse
RUST_LOG=info  ./target/release/morse --input keyboard   # decoded text only