51单片机的矩阵按键扫描的设计C语言程序

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//-----------------------函数声明,变量定义--------------------------------------------------------#include <reg51.h>#define KEY P1//-----------------------变量声明---------------------------------------------------------------------void program_SCANkey(); //程序扫描键盘,供主程序调用void delay(unsigned int N) ;//延时子程序,实现(16*N+24)us的延时bitjudge_hitkey(); //判断是否有键按下,有返回1,没有返回0unsigned char scan_key(); //扫描键盘,返回键值(高四位代表行,低四位代表列)void key_manage(unsigned char keycode); //键盘散转void manage_key1(void); //按键1处理程序void manage_key2(void); //按键2处理程序void manage_key3(void); //按键3处理程序void manage_key4(void); //按键4处理程序//...........每个按键对应一个处理程序,这里//--------------------------------------------------------------------------------------------------//函数名称:program_SCANkey//函数功能:程序扫描键盘,//有键按下完成按键处理,无键按下直接返回//--------------------------------------------------------------------------------------------------void program_SCANkey(){unsigned char key_code;if(judge_hitkey()) //判断是否有键按下{delay(1000); //延时20ms左右,消除抖动干扰if(judge_hitkey()) //判断是否有效按键{key_code=scan_key();while(judge_hitkey()); //等待按键释放key_manage(key_code); //键盘扫描、键盘散转、按键处理}}}//--------------------------------------------------------------------------------------------------//函数名称:delay//入口参数:N//函数功能:延时子程序,实现(16*N+24)us的延时//系统采用11.0592MHz的时钟时,延时满足要求,其它情况需要改动//--------------------------------------------------------------------------------------------------void delay(unsigned int N){int i;for(i=0;i<N;i++);}//--------------------------------------------------------------------------------------------------//函数名称:system_init()//函数功能:初始化设置//设定INT0、INT1及T0、T1的工作方式//--------------------------------------------------------------------------------------------------/* void system_init(void ){TMOD=0x55;//定时器1和定时器0工作在方式1,的计数模式TR0=1; //定时器1和定时器0开始计数TR1=1;ET0=1; //定时器1和定时器0中断允许ET1=1;IT1=0; //选择INT0和INT1为电平触发方式IT0=0;EX0=1; //外部中断允许EX1=0;EA=1; //系统中断允许}//--------------------------------------------------------------------------------------------------//函数名称:INT0_intrupt//函数功能:外部中断0处理程序//--------------------------------------------------------------------------------------------------void INT0_intrupt() interrupt 0 using 1{EA=0; //系统中断禁止delay(1000); //键盘消抖动if(INT_0==0) //判断是否干扰{ //的确有健按下while(INT_0==0);//等待键盘释放delay(1000); //键盘消抖动manage_key1();}EA=1;}*///-------------------------------------------------------------------------------------------------- //函数名称:judge_hitkey//函数功能://判断是否有键按下,有返回1,没有返回0//--------------------------------------------------------------------------------------------------bitjudge_hitkey() //判断是否有键按下,有返回1,没有返回0{unsigned char scancode,keycode;scancode=0xff; //P1.4~P1.7输出全1则无键闭合KEY=scancode;keycode=KEY; //读P1.0~P1.3的状态if(keycode==0xff)return(0); //全1则无键闭合elsereturn(1); //否则有键闭合}//--------------------------------------------------------------------------------------------------//函数名称:scan_key//函数功能://扫描键盘,返回键值(高四位代表行,低四位代表列)//--------------------------------------------------------------------------------------------------unsignedcharscan_key() //扫描键盘,返回键值(高四位代表行,低四位代表列){unsigned char scancode,keycode;scancode=0xef; //键盘扫描码,采用逐行扫描的方法while(scancode!=0xff){KEY=scancode; //输入扫描码,扫描P1.4对应的行keycode=KEY; //读出数据,看是否在此行上的某列键盘被按下if((keycode&0x0f)!=0x0f)break; //扫描到按下的键,则退出scancode=(keycode<<1)|0x0f; //否则,更新扫描码继续扫描}keycode=~keycode;return(keycode);}//--------------------------------------------------------------------------------------------------//函数名称:key_manage//入口参数:keycode扫描键盘返回的键值(高四位代表行,低四位代表列)//函数功能:键盘散转//--------------------------------------------------------------------------------------------------void key_manage(unsigned char keycode){switch(keycode){case0x11:manage_key1();break;case 0x12: manage_key2();break;case 0x14: manage_key3();break;case 0x18: manage_key4();break;case 0x21:manage_key5();break;case 0x22: manage_key6();break;case 0x24: manage_key7();break;case 0x28: manage_key8();break;case 0x41:manage_key9();break;case 0x42: manage_key10();break;case 0x44: manage_key11();break;case 0x48: manage_key12();break;case 0x81:manage_key13();break;case 0x82: manage_key14();break;case 0x84: manage_key15();break;case 0x88: manage_key16();break;// default:}}//-------------------------------------------------------------------------------------------------- //函数名称:manage_key1//函数功能:按键1处理程序//-------------------------------------------------------------------------------------------------- void manage_key1(void){}程序扫描键盘,有键按下完成按键处理,无键按下直接返回。