说明：  IAR for AVR是ATMEL公司推荐的AVR开发环境，其代码编译效率比GCC和ICC高25 到50 ，因此深受欢迎，但其相关的资料却很少，我上传一些能快速上手的资料（包括IAR的扩展关键字，GCC AVR的代码如何移植到IAR等等）
(IAR for AVR is ATMEL' s AVR recommended development environment, its code is more efficient than GCC and ICC to compile a 25 to 50 , so very popular, but very little relevant information, I would upload the information that can quickly get started (including the expansion of IAR keyword, GCC AVR code for how to migrate to IAR, etc.))