8259A中断实验每按动一次SP按钮，产生一次中断信号向8259A发出中断请求，在中断程序里将LED指示等交替点亮和熄灭。同时在数码管上显示“8259-A03”。-8259A interrupt a SP experiment each button pressed, resulting in an interruption of the signal sent to the 8259A interrupt request, in the interruption of program instructions, such as the turn of the LED lit and extinguished. At the same time, digital tube displays　8259-A03 .