4-65-key.rar_fourIO 文件服务

/***************************************** Mega16 4线65键测试程序 CLK = 4MHz by cowboy 2009/08/30 *****************************************/ //硬件连接:PA低4位接键盘，PC接显示口 #include <mega16.h> #include <delay.h> unsigned int key_buff; unsigned char key_step; unsigned char key_num; const unsigned int key_tab[65]= { 0x0900,0x0090,0x0009,0x0204,0x0420,0x0042,0x1124,0x2812,0x4481,0x8248, //A区键码 // 0x0800,0x0400,0x0200,0x0100,0x0080,0x0040,0x0020,0x0010,0x0008,0x0004,0x头0002,0x0001, //B区键码 0x0030,0x0006,0x3936,0x0800,0x0100,0x0c00,0x0003,0x6c93,0x0080,0x0010, //C区键码 0x0600,0x00c0,0xc6c9,0x0008,0x0001,0x0140,0x0028,0x936c,0x0004,0x0200, 0x0180,0x0005,0x55a5,0x0400,0x0020,0x0a00,0x0018,0xaa5a,0x0040,0x0002, 0x0024,0x0012,0x0802,0x0401,0x0480,0x0240,0x0048,0x0120,0x0104,0x0081,0x0810,0x0208, //D区键码 0x0e00,0x01c0,0x0038,0x0007,0xffff,0x0124,0x0812,0x0481,0x0248, //E区键码 0xeedb,0xd7ed,0xbb7e,0x7db7, }; //================ 键盘扫描 ================== unsigned char key_scan(void) { unsigned char i; if(key_step == 0) { //首次扫描 key_buff = ~PINA & 0x0f; //读入4位状态 PORTA &= ~0x01; DDRA |= 0x01; //置A口为输出0 key_step = 1; //切换到下一状态 return 0; } for(i=1;i!=0x10;i<<=1) //其余的4次扫描 { //依次获取3个位的状态 if (key_step == i) continue;//当前主动扫描位，略过 key_buff <<= 1; //移出1空位 if ((i & PINA) == 0) key_buff |= 1; //读入1位 } DDRA &= ~key_step; //置上一扫锚位为上拉输入 PORTA |= key_step; key_step = (key_step & 0x07)<<1;//切换到下一状态 PORTA &= ~key_step; //置下一扫描位输出0 DDRA |= key_step; if (key_step != 0) return 0; //若未完成，返回0 for (i=0;i<65;i++) if (key_buff == key_tab[i]) break;//查找键号 if (i == 65) i=0; else i++; //0表示没按下或错键 if (i == key_num) return 1; //消抖，并返完成标志 key_num = i; //记录本次键号 return 0; } //================ 测试主程序 ================ void main(void) { PORTA = 0x0F; DDRC = 0xFF; while (1) { delay_ms(5); if(key_scan() == 1) //若按键有效则以BCD码输出显示 PORTC = ((key_num/10)<<4) + key_num%10; } }