#define F_CPU 16000000UL
#include<string.h>
#include <avr/io.h>
#include <util/delay.h>
#include <stdlib.h>
#include <stdio.h>




void UART_init()
{
UCSRB |= (1 << RXEN)|(1<<TXEN);
UCSRC |= (1 << URSEL) | (1 << UCSZ0) | (1 << UCSZ1);
UBRRL = 0x67;
}

unsigned char UART_RxChar()
{
while ((UCSRA & (1 << RXC)) == 0);
return(UDR);
}

void UART_TxChar(char ch)
{
    while (! (UCSRA & (1<<UDRE)));    /* Wait for empty transmit buffer*/
    UDR = ch ;
}


void UART_SendString(char *str)
{
    unsigned char j=0;

    while (j<=2)    
    {
        UART_TxChar(str[j]);
        j++;
    }
}



int main(void)

{
static char buff[4];
int i=0,j,k=0;
DDRD =(1<<PD5);
UART_init();
TCCR1A  = 0x82;
TCCR1B  = 0x1B;
ICR1H   = 0x13;
ICR1L    = 0x87;

    while(1)
    {

        while(i<=3)
        {
    buff[I] = UART_RxChar();


    if(buff[3] == '!')
    {
     
    break;
    }

        i++;
        }

        UART_SendString(buff); // for testing whether it is taking the value entered in serial monitor app or not
 
memset(buff,0, sizeof(buff));
i=0;
    _delay_ms(1500);

    }

     
}

Mod edit: code tags

 

Welcome to AAC!
Do you have a question about what you posted?

 

Servo Motor?
Max.

 

thanks for the reply. yes i am having trouble in receiving the string entered in the serial monitor app. i want to control the servo motor by bluetooth by entering OCR1A values in serial monitor app. this was my problem