AVRFreaks.net

#include <avr/io.h>
#include <util/delay.h>
void USARTInit(int ubrr_value);
void USARTWriteChar(char data);
int main(void)
{   
   USARTInit(25); 
    while(1)
    {
      USARTWriteChar('5'); // send the data to USART Tx for transmission
      
    }
}


void USARTInit(int ubrr_value)
{
   //Set Baud rate
   UBRR0L = ubrr_value;
   UBRR0H = (ubrr_value>>8);
    //Enable The receiver and transmitter
   UCSR0B=(1<<RXEN0)|(1<<TXEN0);
 
   UCSR0C=(1<<USBS0)|(3<<UCSZ00);

}

void USARTWriteChar(char data)
{
   while(!(UCSR0A & (1<<UDRE0)))
   {
     
   }
 
  UDR0=data;
}

[b]Code for Receiver side[/b]

#include <avr/io.h>
#include <util/delay.h>
#include <stdlib.h>

void USARTInit(int ubrr_value);
char USARTReadChar();
void USARTWriteChar( char data1);

int main()
{
   char data;
   USARTInit(25);
   while(1)
   {
      data=USARTReadChar();
      USARTWriteChar(data);
   }      
   
}

void USARTInit(int ubrr_value)
{
   //Set Baud rate
   UBRR0L = ubrr_value;
   UBRR0H = (ubrr_value>>8);
   UBRR1L = ubrr_value;
   UBRR1H = (ubrr_value>>8);
    //Enable The receiver and transmitter
   UCSR0B=(1<<RXEN0);
   UCSR0C=(1<<USBS0)|(3<<UCSZ00);
   UCSR1B=(1<<TXEN1);
   UCSR1C=(1<<USBS1)|(3<<UCSZ10);

}
char USARTReadChar()
{
   
   while(!(UCSR0A & (1<<RXC0)))
   {
     
   }
    return UDR0;
}

void USARTWriteChar( char data1)
{
   while(!(UCSR1A & (1<<UDRE1)))
   {
      UDR1=data1;
   }

void USARTWriteChar( char data1)
{
   while(!(UCSR1A & (1<<UDRE1)))
   {
      UDR1=data1;
   }

/*
 * Himel1842Master.c
 *
 * Created: 6/14/2012 1:00:00 AM
 *  Author: larryvc
 */

#define F_CPU 8000000UL      // <-- This is required for and has to be defined before
#include <util/delay.h>      // <-- this.

#include <avr/io.h>

void USARTInit(int ubrr_value);
char USART0ReadChar();
void USART0WriteChar(char data);

// UART Baud Rate
#ifndef BAUDRATE
#define BAUDRATE 57600
#endif

#define BAUD_PRESCALE (((F_CPU / (BAUDRATE * 16UL))) - 1)

int main()
{
   char sentchar = '5';
   char data = sentchar;

   USARTInit(BAUD_PRESCALE);

   while (1) {
      USART0WriteChar(data);
      data = USART0ReadChar();
      if (data == sentchar) {
         // turn on good led
      } else {
         // turn on bad led
      }
      _delay_ms(5);
   }
}

void USARTInit(int ubrr_value)
{
   //Set Baud rate
   UBRR0 = ubrr_value;

   //Enable The receiver and transmitters
   UCSR0B = (1 << RXEN0) | (1 << TXEN0);
   UCSR0C = (1 << USBS0) | (3 << UCSZ00);
}

char USART0ReadChar()
{
   while (!(UCSR0A & (1 << RXC0))) {
   }
   return UDR0;
}

void USART0WriteChar(char data)
{
   while (!(UCSR0A & (1 << UDRE0))) {
   }
   UDR0 = data;
}

/*
 * Himel1842Slave.c
 *
 * Created: 6/14/2012 1:00:00 AM
 *  Author: larryvc
 */

#define F_CPU 8000000UL      // <-- This is required for and has to be defined before
#include <util/delay.h>      // <-- this.

#include <avr/io.h>

void USARTInit(int ubrr_value);
char USART0ReadChar();
void USART0WriteChar(char data);

// UART Baud Rate
#ifndef BAUDRATE
#define BAUDRATE 57600
#endif

#define BAUD_PRESCALE (((F_CPU / (BAUDRATE * 16UL))) - 1)

int main()
{
   char data;

   USARTInit(BAUD_PRESCALE);

   while (1) {
      data = USART0ReadChar();
      USART0WriteChar(data);
      _delay_ms(5);
   }
}

void USARTInit(int ubrr_value)
{
   //Set Baud rate
   UBRR0 = ubrr_value;

   //Enable The receiver and transmitters
   UCSR0B = (1 << RXEN0) | (1 << TXEN0);
   UCSR0C = (1 << USBS0) | (3 << UCSZ00);
}

char USART0ReadChar()
{
   while (!(UCSR0A & (1 << RXC0))) {
   }
   return UDR0;
}

void USART0WriteChar(char data)
{
   while (!(UCSR0A & (1 << UDRE0))) {
   }
   UDR0 = data;
}

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