本程序是用汇编语言实现数字时钟功能的.通过修改8259中断控制器的中断屏蔽寄存器(21H号端口) 打开时间中断, 实时中断, 键盘中断-this procedure is used assembly language digital clock function. By amending the 8259 interrupt controller interrupt masking registers (21H, port) to open the interruption time, real

模拟校园卡管理系统屏蔽键盘操作，直接使用自带软件盘操作-simulation Campus Card Management System Shield keyboard operation, bringing their direct use software disc operation