完全没有固件库，直接对寄存器操作，类似MSP430的编程，可以大大提高效率。 工程中实现LED的操作。可以使用，是IARV5的环境-There is no firmware library, direct-to-register operation, similar to MSP430 programming, can greatly improve efficiency. Works to achieve the operation of LED. Can use, the environ