It's arduino code so there can nobody tell me I'm in the wrong topic
ROFLMAO 
I did post at the beginning somewhere that this is my first attempt at using the Arduino system and the AtMega chips....before I started this project I'd never heard of the Wire library... 
I can read though...and have a background in electronics and computer science. ]
The code is not optimised or elegant...I just posted it to show how I got the AS1130 working with an Arduino.
Anyway....
I now have the 24 x 11 version working and am starting this weekend to solder up the other 2 chips and 264 LEDs which will give me 24 x 22. My plan then is to look into optimising the code and porting it to the Arduino...then I'll look at RGB, but I haven't found any RGB LEDs that I can solder in a very tight matrix.... 
Until the code is optimised and debugged I don't really want to share it because I am changing it all the time...and I haven't even started to include blinking and dot correction yet 
To answer your question...the begin method initialises the I2C bus and sets the internal pullups on SDA and SCL. The beginTransmission method does exactly what it says....