RFID ID20 and atmega16

#include <mega16.h>
#include <delay.h>


#define F_CPU 1000000
#define USART_BAUDRATE 9600
#define BAUD_PRESCALE (((F_CPU / (USART_BAUDRATE * 16))) - 1)



#define rs PORTD.2 // defining rs pin to be PORTC.O
#define rw PORTD.3 //defining rs pin to be PORTC.1
#define en PORTD.4 //defining en pin to be PORCT.2

unsigned char data,message_no,;



unsigned char RFID[]="RFID TAG # is :";



 void init_USART(void)
{
    UCSRA = 0x00; //control register initialization
    UCSRB = 0x98; //enable transmitter and Rx   and rx interrupt
    UCSRC = 0x86; //async, no parity, 1 stop bit,
    
    UBRRL = BAUD_PRESCALE; // Load lower 8-bits of the baud rate value into the low byte of the UBRR register
    UBRRH = (BAUD_PRESCALE >> 8); // Load upper 8-bits of the baud rate value into the high byte of the UBRR register

}



void lcd_cmd(char ch) // a function used to send commands to lcd
{
    rs=0; //setting rs pin to zero (sending a command)
    rw=0; //setting rw pin to zero (to write to registers)
    PORTA=ch; // sending character on the port
    en=1; // setting enable pin
    delay_ms(2); //wait to make sure that the command is written successfully
    en=0; // clearing enable pin
}                 

void lcd_data(char ch) // a function used to send data to lcd
{
    count++;
    rs=1; //setting rs pin to one (sending data)
    rw=0; //setting rw pin to zero (to write to registers)

    PORTA = ch; // sending character on the port
    en=1; // setting enable pin
    delay_ms(2); //wait to make sure that the command is written successfully
    en=0; // clearing enable pin

}

void init_lcd() // a function to initialize LCD
{
 
        lcd_cmd(0x38); // configuring LCD for a two line display
        lcd_cmd(0x0E); //Turning Display and cursor ON
        lcd_cmd(0x01); //Clear Screen Display
        lcd_cmd(0x06); //Increment Cursor
        lcd_cmd(0x0C);   
}




void USART_Rx() 
{ 
    while((UCSRA & 0x80)==0x00); //wait for RXC flag       
    data = UDR;
}




void USART_Tx(char DATA) 
{ 
    while((UCSRA & 0x20)==0x00); //wait for UDRE flag
    UDR = DATA; //load data to UDR for transmission
     
}





interrupt[12] void USART_RX_INTERRUPT()
{
    data = UDR;
    lcd_data(data);
}




  
void main()
{

    DDRA=0XFF;
    
    
    init_lcd(); //initializing LCD 
    init_USART();
    
    #asm("SEI");
    
    
    i=0;
    while(RFID[i] != '\0')
    {
        lcd_data(RFID[i]);
        i++;
    }
    
    lcd_cmd(0xC0);
         
         
         /*
    while(1)
    {       
    
        USART_Rx();
        lcd_data(data);
        
    
    }
       */
       


       while(1); // Receiving by interrupts
    

}

void main()
{

    DDRA=0XFF;
    DDRD.2=1;
    DDRD.3=1;
    DDRD.4=1;
    init_lcd(); //initializing LCD 
    init_USART();

while(1)
    {
       
        USART_Rx();
        lcd_data(data);
    }
}

#define F_CPU 1000000
#define USART_BAUDRATE 9600
#define BAUD_PRESCALE (((F_CPU / (USART_BAUDRATE * 8))) - 1)

#define F_CPU 1000000
#define USART_BAUDRATE 9600
#define BAUD_PRESCALE (((F_CPU / (USART_BAUDRATE * 16))) - 1)