2024-12-5实现16音阶按钮控制并显像管显示字符

单片机的4*4按钮是根据PIN口的高四位和低四位实现的。（其中第几位返回0，显示第几行/列）

我们可以根据btn去存贮其高四位和低四位实现知道第几排第几列。

即可得到一下代码。

//需要自行学习中断相关知识才可以理解interrupt的内容（这里不再赘述）

#include <reg51.h>
sbit SOUNDER = P3^7;
unsigned int SoundFeqInit[]={64620,64400,64524,64580,64684,64777,64820,64898,64920,64980,65030,65058,65110,65157,65178,65218,11451};																																																																																																																																																																																		                                          
unsigned char Musical_note;                                      
unsigned char Mynums[]={
              ~0x3F, //0
              ~0x06, //1
                   ~0x5B, //2
              ~0x4F, //3
              ~0x66, //4
              ~0x6D, //5
              ~0x7D, //6
              ~0x07, //7
              ~0x7F, //8
              ~0x6F, //9
              ~0x77, //A
              ~0x7C, //B
              ~0x39, //C
              ~0x5E, //D
              ~0x79, //E
              ~0x71, //F
              ~0x00};
void delayms(unsigned char t);   
void main(void)
{
    unsigned char btn;
    P2 = 0xFF;
    TMOD = 0x01; 
    IE = 0x82;   
    TR0 = 0;                                                                             
    while(1)
    {
        P2 = 0xf0;                              
        if(0xf0 != (P2&0xf0))  
        {
            delayms(10);                      
            if(0xf0 != (btn=P2&0xf0))  
            {
                P2 = 0x0f;
                btn |= P2;
                TR0 = 1;
                switch(btn)
                {    
                    case 0xee:
                        Musical_note = 0;
                        P0=Mynums[0];
                        break; 
                    case 0xde:
                        Musical_note = 1;
                        P0=Mynums[1];
                        break;
                    case 0xbe:
                        Musical_note = 2;
                        P0=Mynums[2];
                        break;
                    case 0x7e:
                        Musical_note = 3;
                        P0=Mynums[3];
                        break;
                    case 0xed:
                        Musical_note = 4;
                        P0=Mynums[4];
                        break;
                    case 0xdd:
                        Musical_note = 5;
                        P0=Mynums[5];
                        break;
                    case 0xbd:
                        Musical_note = 6;
                        P0=Mynums[6];
                        break;
                    case 0x7d:
                        Musical_note = 7;
                        P0=Mynums[7];
                        break;
                    case 0xeb:
                        Musical_note = 8;
                        P0=Mynums[8];
                        break;
                    case 0xdb:
                        Musical_note = 9;
                        P0=Mynums[9];
                        break;
                    case 0xbb:                                              
                        Musical_note = 10;
                        P0=Mynums[10];
                        break;
                    case 0x7b:                                              
                        Musical_note = 11;
                        P0=Mynums[11];
                        break;
                    case 0xe7:                                              
                        Musical_note = 12;
                        P0=Mynums[12];
                        break;
                    case 0xd7:                                              
                        Musical_note = 13;
                        P0=Mynums[13];
                        break;
                    case 0xb7:                                              
                        Musical_note = 14;
                        P0=Mynums[14];
                        break;
                    case 0x77:                                              
                        Musical_note = 15;
                        P0=Mynums[15];
                        break;
                    default:TR0 = 0;break;
                }
            }
        } 
        if(0xf0 == P2)
        {
            TR0 = 0;
            SOUNDER = 1;
        }
        delayms(10);    
    }
}

void T0Sev(void) interrupt 1
{
    TH0 =  SoundFeqInit[Musical_note]/256;
    TL0 =  SoundFeqInit[Musical_note]%256;
    SOUNDER = ~SOUNDER;                                                 
}

void delayms(unsigned char t)
{
    unsigned int i,k;
    for(k=0;k<t;k++)
    {
        for(i=0;i<500;i++){;}     // 500*2us= 1ms
    }
}