次程序主用是针对ATMEGAL128单片机进行外部中断 双串口通信 4*4按键的操作程序 本程序主要是应用在超市智能购物系统的设计中的各个部分程序设计应用时的程序，程序是通过ICCAVR软件进行编译链接的，通过AVRstudio软件下载到单片机中的-Main program used for ATMEGAL128 microcontroller external interrupt 4* 4 buttons Two serial communication operating procedures of this program is the application of the various parts of the program design used in the supermarket intelligent shopping system design program, the program is ICCAVR softwarecompiled and linked by AVRstudio software downloaded to the microcontroller