针对AVR ATXMEGA128A1单片机的BOOTLOADER自编程程序工程。已测试通过，稍微做改动也可以作为别的AVR型号自编程用。-For AVR ATXMEGA128A1 microcontroller BOOTLOADER self-programming program works. Have been tested, do a little changes that can be used as self-programming with other AVR models.