A simple interactive interface over a serial connection to an ATmega328P. Something I can hopefully share with my nephew back home :-)
$ minicom -D /dev/ttyUSB0 -b 4800
...
Type 'help' if you need usage instructions
>>> help
Executing command: 'help'
Usage:
led on to light me up
led off to go to sleep...
>>>
Type 'help' if you need usage instructions
>>> led on
Executing command: 'led on'
Type 'help' if you need usage instructions
>>> led off
Executing command: 'led off'
Type 'help' if you need usage instructions
>>> asdfad
Command 'asdfad' is not recognized...
Available commands are:
led on
led off
help
Type 'help' if you need usage instructions
>>>