Going from an embedded processor like a PIC to a Linux environment can be a jump, but we have a variety of guides and manuals posted to try to make it easier for you.

Have you checked out http://support.logicpd.co...M3703TorpedoSOM.aspx

If you haven't already done so, you will need to register your eval kit in order to access all the files. Once you have done that, you will find several documents and examples on how to toggle GPIO pins (AN527) as well as a Linux Training manual, BSP User guide, and Hardware design files which will contain schematics. In the schematics, it will show each pin on the module, where it is connected, and it's GPIO number.

The BSP User Guide in section 5.1 also has a "Hello World" example to help get you started.

Hopefully that will help point you in the right directions for getting started.

-Adam