单片机控制一个4位的共阴数码管通电的状态下显示时间的程序答:include <reg52.h> define uint unsigned int define uchar unsigned char sbit PRESS1=P1^0;sbit PRESS2=P1^1;sbit PRESS3=P1^2;uint a[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};//0到9 uint b[]={0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f};int miao=...
求份微机原理与接口技术的试题(含答案)答:41.(10分)用8255A作打印机接口的硬件连接和驱动程序如下所示,8255A的入口地址为80H-83H,阅读此程序回答下列问题: (1)所采用的数据控制方式? (2)所传送的字节数? (3)8255A的工作方式? MOV AL,081H OUT 083H,AL MOV BX,3000H MOV CX,64H MOV AL,0DH OUT 083H,AL STT: IN AL,082H AND AL,08...