单片机原理及应用(人机界面接口技术)

第十三章人机界面接口技术(人机交互)13.1显示接口技术13.2常用显示设备LED、七段数码管、LCM、LCD等；13.3常用显示设备—LED（发光二极管）13.4常用显示设备—数码管13.4.1单个8段LED数码管的结构如下:abcdefghabcdefghcomabcdefghcom共阳型共阴型13.4.2组合式的数码管有两种显示方式：动态显示接口和静态显示接口ahhaahha1234多位数码管内部结构图13.4.3单片机控制单个LED数码管显示数字(0-9)gfabedch80C51P07P06P05P04P03P02P01P00P2.7P04P00P01P06P05P02comP07comcomP03comVccP0.7P0.6P0.5P0.4P0.3P0.2P0.1P0.0数码管与单片机的硬件连接图13.4.4字形码的确定表5-1字符0-9的字形引脚P07P06P05P04P03P02P01P00字形码(共阴--/共阳)字段HGFEDCBA011000000C0H--3FH111111001F9H–06H210100100A4H–5BH310110000B0H–4FH41001100199H–66H51001001092H–6DH61000001082H–7DH711111000F8H–07H81000000080H–7FH91011000090H–6FH13.4.5单片机控制多个LED数码管显示数字(静态显示方式)Q0Q7ABCLKMR+5VTXDRXD80C51+5VhgfedcbafghABabcdeMRCLKMRedchgfCLKABbaQ0Q7Q0Q7静态显示接口13.4.6单片机控制多个LED数码管显示数字(动态显示方式)a89S51P0.7P0.6P0.5P0.4P0.3P0.2P0.1P0.0P2.7P2.6P00P02P01P03P2.4P2.5P2.3P2.2P04P05P06P07bcdefghP07P06P05P04P03P02P01P00P22P23P24P25P26P27P27P26P25P24P23P22123456Vcc•动态显示接口上机操作要求(1)单个共阳型7段数码实验，循环显示0-9数字，写出源程序并编译下载运行；(2)4个共阳型7段数码实验，固定显示1234数字，写出源程序并编译下载运行；(3)4个共阳型7段数码实验，实现计时功能，递减计时(每秒)：从9999-0000变化，递增计时(每秒)：从0000-9999变化）写出源程序并编译下载运行；实现秒表功能13.5常用显示设备—LCM(LCD)DATAPORTP0.0DB0P0.7DB7RSR/WEP2.5P2.6P2.7+5VGNDVLBLKBLA80C51连接方式如图所示字符型液晶显示器的使用使用字符型液晶显示器通用驱动程序初始化液晶显示器命令清屏命令（CLRLCD）光标控制命令（SETCUR）写字符命令（WRITECHAR）字符串命令（WRITESTRING）13.6键盘接口•13.6.1独立式按键设计P3.2P3.3P3.4P3.5VCC80C51GND按键接法13.6.2矩阵式按键设计键按下闭合稳定键释放后沿抖动前沿抖动键的抖动R2410KR2510K8910IC8C74LS00111213IC8D74LS00S18SWSPDT+5VINT0_113.6.3按键防抖动设计13.6.4读取按键键值程序设计1、独立式按键键值读取if(P3_2==0)/*开始*/{for(j=0;j1000;j++);/*用for循环延时，再读键*/if(P3_2==0)/*开始*/{/*此处要加用户程序*/}}2、矩阵式按键键值读取键盘扫描有键闭合？延时去抖动扫描键盘计算键值有键闭合？键已释放？设立有键按下标志退出清有键按下标志NYYYNN键盘扫描流程图for(i=0;i4;i++)/*4X4扫描,检验是否有键按下*/{j=i+4;clrbit(P0,j);/*P1.4,P1.5,P1.6*/for(us=0;us1000;us++);/*为防抖动再次读键8952*/KeyValue=P0;/*读入键值*/if((KeyValue&0x0f)!=0x0f)/*有键按下*/{for(us=0;us10000;us++);/*为防抖动再次读键8952*/if(KeyValue==P0){KeyMenu();/*菜单处理*/}}setbit(P0,j);}