The Arduino microcontroller was named after Arduin of Ivrea. Arduin was an Italian king who lived over a millennium ago. His wife was Bertha of Burgundy and this library is named in her honor.
And what is this library? you might ask. Well, this library exposes the inner-workings of the Arduino to high-order programming languages. Sure, C is great and we can program the Arduino with it. But Ruby is more powerful, Java more ubiquitous, and C# more... uh... Microsofty. But most importantly, the hardware that these languages run on has more ready and sophisticated access to things like networking, video, and sound. Things that the Arduino can do if you buy more hardware but something like say... a Raspberry Pi can do just as easily.
How It Works
A standard sketch is loaded on the Arduino that responds to commands sent over the serial port from a computer to the Arduino. These command will do things like set a pin to output, read the value of a pin, read an analog value, set the value of pin, etc. Each command will respond with an appropriate status for the command.
For example, using a simple terminal an exchange might look something like this:
version OK version=1.0.0 setPin pin=12 mode=OUTPUT value=LOW OK pin=12 mode=OUTPUT value=LOW setPin pin=12 value=HIGH OK pin=12 mode=OUTPUT value=HIGH queryPin pin=12 OK pin=12 mode=OUTPUT value=HIGH setPin pin=13 mode=INPUT OK pin=13 mode=INPUT value=HIGH queryPin pin=13 OK pin=13 mode=INPUT value=HIGH
With this protocol in place the second piece of Bertha shines. Out protocol is wrapped in an API for several of the more common and popular languages. Ruby is planned first and the API will look something like this.
Bertha.open <port> do |bertha| bertha.version # returns 1.0.0 bertha.pin_out 1 bertha.pin_on 1 bertha.pin_in 2 bertha.pin 2 # returns true end
Current the standard sketch is being developed and the protocol is totally subject to change. Once completed, however, gems, jars, and packages galore shall be build. Maybe you'll build some of them yourself?