Design of multi-channel answering machine based on single chip microcomputer

The circuit can realize the function of 9-way buzzer. After one person presses it, it will be invalid for others to press it. They need to be reset before they can answer again.

The following figure is a Proteus simulation diagram:

The following figure is the schematic diagram:

The following figure is the PCB diagram:

The picture below is a real picture, taken with a mobile phone, so it is not very clear

The following is the source program:

#include
#define uint unsigned int
#define uchar unsigned char
uchar code table[]={             //Nude tube coding without decimal point
0xc0,0xf9,0xa4,0xb0,
0x99,0x92,0x82,0xf8,
0x80,0x90};
uchar num;
sbit beep=P3^6;
sbit k1=P1^0;
sbit k2=P1^1;
sbit k3=P1^2;
sbit k4=P1^3;
sbit k5=P1^4;
sbit k6=P1^5;
sbit k7=P1^6;
sbit k8=P1^7;
sbit k9=P3^0;
void keyscan();
void delay(uint z)
{
 uint x,y;
 for(x=z;x>0;x--)
 for(y=5000;y>0;y--);
}

void main()
{
 while(1)
 {
  keyscan();
 }
}

void keyscan()
{ 
 P0=0xc0;
 P2=0xfe;
 if(k1==0)
 {
  beep=0;
  delay(5);
  beep=1;
  P0=table[1];
  delay(10000);
 }
 else if( k2==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[2];
  delay(10000);
 }
 else if(k3==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[3];
  delay(10000);
 }
 else if(k4==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[4];
  delay(10000) ;
 }
 else if(k5==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[5];
  delay(10000);
 }
 else if(k6==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[6];
  delay(10000);
 }
 else if(k7==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[7] ;
  delay(10000);
 }
 else if(k8==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[8];
  delay(10000);
 }
 else if(k9==0)
 { 
  beep=0;
  delay(5);
  beep=1;
  P0=table[9];
  delay(10000);
 }
}