avr109资料手册

　　This application note describes how an

　　AVR with the SPM instruction can be

　　configured for self-programming. The

　　AVR communicates via the UART with

　　a PC running AVRprog programming

　　software. This enables FLASH and

　　EEPROM programming without the need

　　for an external programmer.

　　A Boot Load program is placed inside

　　the Boot Section of the Flash memory.

　　This program handles communication

　　with the host PC， and facilitates programming of both Flash and EEPROM

　　Once programmed， different levels of

　　protection can be used to protect the

　　memories. The AVR offers a unique

　　flexibility， setting different levels of protection on the Boot and Application

　　areas of the Flash memory. Individual

　　protection levels can be selected for both

　　portions of memory.