Rust and Cargo program for Arduino Uno

Features:

1. Uses timer interrupts to blink the LED.
2. Echos back characters sent via the built-in serial device.
3. Echos back characters sent via the built-in serial device using futures.

The code is written completely in Rust and a small amount of assembly! We avoid using any of the GCC startup files.

See the official blink example, which makes use of some GCC-provided code.

High-level instructions

1. Follow the official instructions to install avr-gcc and avrdude. Additionally install picocom. For example, using Homebrew:

   brew install picocom
   

   avr-gcc is used as the linker, avrdude uploads the finished code, and picocom is used as the serial terminal.

2. Build the code: make

3. Upload the code: make program

4. Connect the serial terminal: make connect-terminal