Library documentation

Hi all,
I'm trying to use an Arduino Due to read out the speed of something onto an LCD panel.
Unfortunately I can't DMA to the panel (because of the wiring) so I want to use a TC channel to count the pulses and have the main loop calculate the speed and display it.

The main problem I am having is trying to find the right documentation for the library that my code is compiled with.

It seems that Atmel have moved on and their documented APIs for the SAM3 are quite different and I'd like to look at some documentation & sample code if possible to remove guess work.

Does anyone know where I'd find some?

Thanks.