(2.9.5)--案例3：三个按键四位动态数码管显示秒表按下S1清零.pdf
案例案例：三个按键三个按键 四位动态数码管四位动态数码管 显显示秒表示秒表 按下按下 S1S1 清零清零1.原理图原理图2.数码管显示字符与端口数据对应关系数码管显示字符与端口数据对应关系编号显示字符端口电平P2 端口数据P2.7aP2.6fP2.5bP2.4eP2.3dP2.2DPP2.1cP2.0g00000001010 x0511110111010 xDD22010001100 x4633010101000 x5444100111000 x9C55001101000 x3466001001000 x2477010111010 x5D88000001000 x0499000101000 x1410A000011000 x0C11B101001000 xA4编号显示字符端口电平P2 端口数据P2.7aP2.6fP2.5bP2.4eP2.3dP2.2DPP2.1cP2.0g12C111001100 xE613D110001000 xC414E001001100 x2615F001011100 x2E16全灭111111110 xFF3.代码代码/*头文件区域*/#include/*常量定义区*/#define P2_INIT 0 xFF#define P2M1_INIT 0 x00#define P2M0_INIT 0 x00#define P0_INIT 0 x0F#define P0M1_INIT 0 x00#define P0M0_INIT 0 x00/设置 P32 P33 P34 为输入脚#define P3_INIT 0 x1C#define P3M1_INIT 0 x00#define P3M0_INIT 0 x00/*变量定义区*/unsigned char Cnt_2ms=0,Cnt_10ms=0,Cnt_1s=0,Second=0;unsigned char Scan_Cnt=0;/片选变量，该变量为 0 显示数码管第 0 位为 1 显示数码管第 1 位为 2 显示数码管第 2 位为 3 显示数码管第 3 位unsignedcharconstDsp_Seg17=0 x05,0 xDD,0 x46,0 x54,0 x9C,0 x34,0 x24,0 x5D,0 x04,0 x14,0 x0C,0 xA4,0 xE6,0 xC4,0 x26,0 x2E,0 xFF;/数码管显示数组定义unsigned char const Scan_Table4=0 xFE,0 xFD,0 xEF,0 xF7;/显示片选端口表 按照unsigned char Dsp_Table4=0,0,0,0;/显示片选端口组织表/按键变量定义unsigned char Key_Buffer=1;/按键缓冲变量unsigned char Key_Effect=1;/有效按键变量unsigned char Key_Cnt=0;/按键消抖变量unsigned char Key_Code=0;/键码structunsigned char dsp_flg:1;/显示标记unsigned char read_key:1;/按键标记unsigned char:1;unsigned char:1;unsigned char:1;unsigned char:3;TimeFlg=0;/*函数声明区*/void MCU_Init();void Delay(unsigned char);void Dsp_LED();void ReadKey(void);void KeyOpt(void);void main()/*初始化区*/MCU_Init();/*主循环*/while(1)if(TimeFlg.read_key=1)/2ms 扫描按键TimeFlg.read_key=0;ReadKey();if(TimeFlg.dsp_flg=1)TimeFlg.dsp_flg=0;Dsp_LED();/初始化函数void MCU_Init()P0=P0_INIT;P0M1=P0M1_INIT;P0M0=P0M0_INIT;P2=P2_INIT;P2M1=P2M1_INIT;P2M0=P2M0_INIT;P3=P3_INIT;P3M1=P3M1_INIT;P3M0=P3M0_INIT;/定时器 0 初始化AUXR&=0 x80;/定时器 0 为 12T 模式TMOD=0 x00;/模式 0,16 位自动重载TL0=0 x83;/设置定时初值TH0=0 xFF;/设置定时初值TR0=1;/开始计时ET0=1;/Enable Timer0 interruptIE|=0 x80;/开总中断/显示函数void Dsp_LED()Dsp_Table2=Dsp_SegSecond%10&0 xFB;/显示秒的个位和点Dsp_Table3=Dsp_SegSecond/10;/显示秒的十位Dsp_Table0=Dsp_SegCnt_1s%10;/显示微秒的百位Dsp_Table1=Dsp_SegCnt_1s/10;/显示微秒的十位/*Dsp_Table3=Dsp_Seg16;Dsp_Table2=Dsp_Seg16;Dsp_Table1=Dsp_Seg16;/不显示Dsp_Table0=Dsp_SegKey_Code;/显示键码*/void ReadKey(void)/读键函数Key_Buffer=P3&0 x1C;/读端口状态/Key_Buffer=P3|0 x1C;/读端口状态if(Key_Buffer=Key_Effect)/按键不放不处理Key_Cnt=0;return;elseKey_Cnt+;if(Key_Cnt=5)/读键 5 次消抖Key_Cnt=0;Key_Effect=Key_Buffer;/送有效键值，后续处理KeyOpt();/有效键处理void KeyOpt(void)/按键处理函数switch(Key_Effect)case 0 x1C:/没有按下按键Key_Code=0;break;case 0 x18:/按下按键 S1Second=0;Cnt_1s=0;Key_Code=1;break;case 0 x14:/按下按键 S2Key_Code=2;break;case 0 x0C:/按下按键 S3Key_Code=3;break;/中断函数 2ms 200ms 1s 平台void INT_Timer0()interrupt 1/中断函数Cnt_2ms+;if(Cnt_2ms=16)/2ms 平台Cnt_2ms=0;TimeFlg.read_key=1;/LED 片选切换Scan_Cnt+;if(Scan_Cnt=4)Scan_Cnt=0;P0=P0|0 x0B;/关闭所有片选P2=Dsp_TableScan_Cnt;/送段码P0=P0&Scan_TableScan_Cnt;/开启相应片选/计时Cnt_10ms+;if(Cnt_10ms=5)/10ms 平台Cnt_10ms=0;TimeFlg.dsp_flg=1;Cnt_1s+;if(Cnt_1s=100)/1s 平台Cnt_1s=0;Second+;if(Second=60)Second=0;
