方式1的输出实验电路，每按一次单脉冲按钮

产生一个正脉冲使8255产生一次中断请求，让CPU进行一次中断服务：依次输出01H、02H，04H，08H，10H，20H，40H，80H使L0～L7依次发光，中断８次结束。-Interface Experiment 1 way programmable parallel interface 8255

Experimental circuit 1 output mode, a single pulse each time the button produces a positive pulse to 8255 to generate an interrupt request to CPU into the

An interrupt service line: turn out 01H, 02H, 04H, 08H, 10H, 20H, 40H, 80H to L0 ~ L7 followed by light, interrupted

8 times over.