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AVR128 Program - Matrix Buttons

Publisher:心灵飞翔Latest update time:2016-03-04 Source: eefocusKeywords：AVR128 Reading articles on mobile phones Scan QR code
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#include  
#include
#define uchar unsigned char
#define uint unsigned int
      
void Delayms(uint MS);     
 
uchar key_scan(void);
void init_io(void);
 
uchar led_discode[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,
                       0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e,0xff};
                     
uchar   key_val=0;
 
void main (viod)
{
     uchar key_io;
init_io();
while(1)
{
     PORTD=0XF0;
 Delayms(5);
 key_io=PIND & 0xf0;
     if(key_io !=0xf0)
     {
     PORTD=0XF0;
     Delayms(1);
   key_io=PIND & 0xf0;
     if(key_io !=0xf0)
   {
  key_val=key_scan();   
      key_val |= key_io ;
   }
     switch(key_val)
              {     
               case 0xee: key_val=0x00;   break;    //Key K1
                          
 case 0xde: key_val=0x01;   break;    //Key K2
                        
 case 0xbe: key_val=0x02;   break;    //Key K3
                        
 case 0x7e: key_val=0x03;   break;    //Key K4
                          
 case 0xed: key_val=0x04;   break;    //Key K5
                         
 case 0xdd: key_val=0x05;   break;    //Key K6
                        
 case 0xbd: key_val=0x06;   break;    //Key K7
                       
 case 0x7d: key_val=0x07;   break;    //Key K8
                          
 case 0xeb: key_val=0x08;   break;    //Press key K9
                        
 case 0xdb: key_val=0x09;   break;    //Key K10
                        
 case 0xbb: key_val=0x0a;   break;    //Key K11
                        
 case 0x7b: key_val=0x0b;   break;    //Key K12
                          
 case 0xe7: key_val=0x0c;   break;    //Key K13
                        
 case 0xd7: key_val=0x0d;   break;    //key K14
                            
                 case 0xb7: key_val=0x0e;   break;    //Key K15
                        
 case 0x77: key_val=0x0f;   break;   //key K16                
              }   
 }                   
 PORTD=0XF0;
 key_io=PIND & 0xf0;
 while(key_io !=0xf0)
 {
 key_io=PIND & 0xf0;
 }
 PORTC=led_discode[key_val];    
}          
}
 
void init_io(void)
{
     DDRA=0XFF;
PORT=0XFF;
 
DDRB=0XFF;             
     PORTB=0XFF;             
 
DDRC=0XFF;              
PORTC=0XFF;             
 
DDRD=0X0F;              
     PORTD=0XF0;   
 
DDRF=0X0E;
PORTF=0X0E;
PORTF&=0XF7;            
 
DDRB |=0X10;           
PORTB|=0X10;         
}
 
uchar key_scan(void)
{
     fly m,temp=0xf7;
for(m=0;m<4;m++)
{
    PORTD=temp | 0xf0;
    Delayms(1);
if((PIND & 0XF0)!=0XF0)
    return(temp & 0x0f);
temp>>=1;
}
}
 
void Delayms(uint MS)  
{
     uint i,j;
     for( i=0;i
     for(j=0;j<1141;j++);
}
 
Keywords：AVR128 Reference address：AVR128 Program - Matrix Buttons

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Professor at Beihang University, dedicated to promoting microcontrollers and embedded systems for over 20 years.

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