This is a port of FreeRTOS 6.1.0 to the Atmel AT91SAM3U4 chip on the SAM3U-EK development board, using the GCC toolchain. It started off as a modification of the existing official port using the IAR toolchain.
The directory structure has been slightly modified, primarily to make the AT91Lib directory look more like Atmel's at91lib code package (hard to call something that depends on user headers a "library"). The ZIP file is only the CORTEX_AT91SAM3U256_GCC directory; it is intended to be unpacked into the Demo directory of an existing FreeRTOS 6.1.0 installation.
There are a lot of things in the at91lib and demo code that could be improved or optimized, but I left them alone in the interest of not changing more than I needed to. This code is intended to be integrated into the official sources. Until that happens, if anyone knows where there's a script for automatically updating the boilerplate at the head of every FreeRTOS file, please let me know. Those changes make it hard to 'diff' between releases.
Finally, it would be nice if the FreeRTOS developers used the CMSIS names for exception handlers and interrupt service routines in Source/portable/GCC/ARM_CM3*, so that board_cstartup_gnu.c did not have to be modified depending on whether or not FreeRTOS was being used.
Thanks for the OS. ^_^