An AT91SAM7 Serial-IO/UART and interrupt example for the Atmel AT91SAM7S64 (should work with all AT91SAM after minimal changes) which demonstrates UART interfacing (serial I/O), interrupt/exception-handling and lots of gcc-specials.

 void uart_init()：uart初始化配置，配置相应IO口状态、奇偶校验选择以及波特率等参数。  unsigned char uart_max_data_get(unsigned char *buf) ：通过协议计算等获取串口通讯的最大数据长度，用于判断这一帧数据接收完全  unsigned char uart_recive(unsigned char *buf)：串口接收函数，接收到的数据存储在buf中。 