A simple AVR access control system code

After the 1602 and key program debugging, encoding, password comparison, gatekeeping, and some processing of error codes are improved, they will not be uploaded. Here I will only leave a very basic version backup for myself.

#define F_CPU 4000000
#includeAVR-20090313\avr\include\avr\io.h>
#include
#includeLCD1602.h>
typedef unsigned char uchar;
typedef unsigned int uint;
static char str1[]={"begining"}; //Power-on system working display
static char str2[]={"enter pass"}; //Start entering the password to open the door
static char str3[]={"set pass"}; //Enter the encoding display
//Port direction, '1' output, '0' input.
#define BUTION_DDRN DDRD //Button port direction
#define BUTION_PORT PORTD //Button port
#define BUTION_DDRN_INT(); DDRD=0xf0; //Button port direction initialization
#define BUTION_PORT_REL (PIND&0x0f)
static uchar sweep[4]={0xef,0xdf,0xbf,0x7f}; //Four lines of scan port value
uchar pass_buf[9]; //password cache unit
uchar bution(void); //Matrix key program
uchar set_scan(void); //Encoding key scanning program
int main(void)
{uchar i,j;
Lcd_Init(); //LCD initialization function
Lcd_SetXy(0,0); //Set display coordinate function
Lcd_PutStr(&str1[0]);
_delay_ms(500); //Delay 1 second
Lcd_Init(); //LCD initialization function
Lcd_SetXy(0,0); //Set display coordinate function
Lcd_PutStr(&str2[0]);
Lcd_SetXy(0,1); //Set display coordinate function
for(;;)
  {for(i=0;i<9;i++)
    {do{j=set_scan();//Encoding key
     if(j==0x01)j=0xfe;break;//j=0xfe encoding key pressed
     j=bution(); ///Key scan
     if((j!=0xff)&&(j!=0x0a))break;
     }while(1);
    if(j==0xfe)break;//j=0xfe coded button pressed
    pass_buf=j;
    if(j==0x0b)break;
    }
  if()
  }
return 0x00;
}
uchar bution(void) //Matrix key program
{uchar i, key_buf; //key value cache unit
BUTION_DDRN_INT(); //Button port direction initialization
for(i=0;i<4;i++)//four lines scan
  {BUTION_PORT=sweep[i]; //Scan line
  _delay_us(20);
  key_buf=BUTION_PORT_REL;
  if(key_buf!=0x0f)//A key is pressed
    {_delay_ms(20); //delay de-jitter
    if(key_buf==BUTION_PORT_REL)//Key confirmation
      {key_buf=(~key_buf)&0x0f;
      switch(key_buf)
        {case 0x01:key_buf=0x00;break;
        case 0x02:key_buf=0x01;break;
        case 0x04:key_buf=0x02;break;
        case 0x08:key_buf=0x03;break;
        default:key_buf=0xff;
        }
      key_buf=i*4+key_buf;
      switch(key_buf)
        {case 0x00:key_buf='1';break;//"1" key
        case 0x01:key_buf='2';break;//"2" key
        case 0x02:key_buf='3';break;//"3" key
        case 0x03:key_buf=0xff;break;//"" key

        case 0x04:key_buf='4';break;//"4" key
        case 0x05:key_buf='5';break;//"5" key
        case 0x06:key_buf='6';break;//"6" key
        case 0x07:key_buf=0xff;break;//"" key

        case 0x08:key_buf='7';break;//"7" key
        case 0x09:key_buf='8';break;//"8" key
        case 0x0a:key_buf='9';break;//"9" key
        case 0x0b:key_buf=0xff;break;//"" key

        case 0x0c:key_buf='*';break;//"*" key
        case 0x0d:key_buf='0';break;//"0" key
        case 0x0e:key_buf='#';break;//"#" key
        case 0x0f:key_buf=0xff;break;//"" key
        default:key_buf=0xff;
        }
      while(BUTION_PORT_REL!=0x0f)
      {_delay_us(20);
      while(BUTION_PORT_REL!=0x0f);
      }//Wait for the button to pop up
      break;//Pick out from four scans
      }
    else key_buf=0xff;
    }
  else key_buf=0xff;
  }
return key_buf;
}
uchar set_scan(void)
{
}