Each real time kernel port consists of three files that contain the core kernel components and are common to every port, and one or more files that are specific to a particular microcontroller and/or compiler. + The FreeRTOS/Source/Portable/MemMang directory contains the three sample memory allocators as described on the http://www.FreeRTOS.org WEB site. + The other directories each contain files specific to a particular microcontroller or compiler. For example, if you are interested in the GCC port for the ATMega323 microcontroller then the port specific files are contained in FreeRTOS/Source/Portable/GCC/ATMega323 directory. If this is the only port you are interested in then all the other directories can be ignored.