说明：  ATmega128具备引导加载支持的用户程序自编程功能(In-Sysytem Programming by On-它提供了一个真正的由MCU本身自动下载和更新
(ATmega128 bootloader with support user program from the programming function (In-Sysytem Programming by On-It provides a real per se by the MCU to automatically download and update)