hmm teensy press keys time

First install the required bits:

rustup target add thumbv7em-none-eabihf
rustup component add llvm-tools-preview
cargo install cargo-binutils

You will need the teensy_loader_cli program as well, there is an AUR repo of the same name which I installed.

Now to build and flash the teensy:

cd firmware

# Build the firmware hex file
cargo objcopy --release -- -O ihex firmware.hex 

# Flash the firmware
teensy_loader_cli --mcu=TEENSY41 -w firmware.hex

Connect the serial over USB to the teensy and whatever computer you want to send keypresses from. Now connect the teensy to the computer you want to send keypresses to.

An example setup could look like this:

You can now run the client:

cd client
cargo run --release

It will pop up a dialog if there is ambiguity about what serial port to send over or what keyboard to read keypresses from.

socat once again saves the day :)

On the machine with a keyboard we use socat to create a virtual serial port and forward it over TCP:

socat PTY,link=serial,rawer,b115200 TCP4:10.0.0.1:12345

On the machine with a serial port we use socat to create to listen on TCP and forward data over the serial port:

socat TCP-LISTEN:12345,fork,reuseaddr /dev/ttyUSB0,rawer,b115200