This directory contains "applets" - simple programs to let us test the callbacks into CFE. You should be able to compile these programs and load them via the TFTP loader in CFE, and when run, they will call the APIs in CFE to display messages and such. The files cfe_api.c, cfe_api.h, and cfe_api_int.h are versions of the same files from ../applets, customized to build with this stand-alone build environment. Typically you won't want to copy these. Instead, you'll want to copy the versions in ../applets and customize them as needed. Pay particular attention to the MIPS calling conventions you are using. In particular, CFE uses 64-bit register values. If you compile your program with -mips1 or -mips2, the 64-bit arguments will be passed as 2 32-bt registers. In most cases, CFE only uses the lower 32 bits, since it can be called from either 32 or 64-bit applications.