用8086，8255，8259和8254构造系统实现对指示灯控制。

8255的PA0，PA1,PA2的三位DIP开关，通过DIP开关的闭合状态决定接在

PB口上的八个指示灯之一闪烁。如PA2,PA1,PA0为000时，PB0上所接的指

示灯闪烁，其余灯熄灭。要求闪烁频率为每秒10次。设8259地址为20H和

21H，8255地址为60H～63H，8254地址为40H～43H,时钟频率为50KHz，

8259中断向量号为70H和71H.试设计硬件连接电路，填写中断向量表，编

写全部初始化程序，完成控制程序编写。-8086,8255,8259 and 8254 by tectonic system of light control. 8255 of PA0, PA1, PA2 three DIP switches, DIP switches, through the closed state in the PB I decided to take on one of the eight indicator light flashes. Such as PA2, PA1, PA0 for 000 hours, PB0 on the indicator light flashes then the remaining light extinguish. Requirements flicker frequency of 10 times per second. 8259 address 20H located and 21H, 8255 address 60H ~ 63H, 8254 address 40H ~ 43H, the clock frequency of 50KHz, 8259 interrupt vector number is 70H and 71H. Try to design hardware to connect the circuit to fill in Interrupt Vector Table, the preparation of all the early the beginning of the procedure to complete the preparation of control procedures.