这是一个AVR单片机（atmega128,ICCAVR7环境下，硬件连接：PD口接8个发光LED,init0接独立按键）的外部中断例子代码，程序开始执行后，第一个LED以0.5s频率闪烁，当按键按下以后，八个LED同时亮3s，然后恢复一个LED闪烁。-This is an AVR microcontroller (atmega128, ICCAVR7 environment, the hardware connection: PD mouth then eight light-emitting LED, init0 take independent keys) external interrupt example code, the program begins execution, the first LED flashes to 0.5s, when After the button is pressed, eight LED also lit 3s, then resume a LED flash.