Sergiv,
I don't know which LabVIEW Embedded product you are using (LabVIEW for ARM or the Microprocessor SDK) but there are shipping examples that walk you through basic DIO and Serial communication (for the LM3S8962) that you should be able to port over to your hardware. The two shipping examples are called DIO.lvproj and Serial Comm.lvproj. You can find these shipping examples in the Example Finder (Help>>Find Examples..) under the section called Toolkits and Modules and then under the ARM section.
