roboforum.ru

volatile unsigned char tx_buffer_index = 0 , tx_buffer[uart_buffer_size] , tx_counter = 0;
volatile unsigned char rx_buffer_index = 0 , rx_buffer[uart_buffer_size] , rx_counter = 0;
volatile unsigned char global_flag = 0;


interrupt[USART_RXC]void ReciveComplite(void)
{
unsigned char data = 0 ;

data = UCSRB;
data = UDR;

if( (rx_buffer_index != uart_buffer_size) && check_valid_symbol(data) )
{
rx_buffer[rx_buffer_index] = data;
rx_buffer_index++;
set_bit(global_flag,take_data_flag);
};
}

interrupt[USART_DRE]void udre(void)
{                           
tx_counter++;
if( tx_counter != tx_buffer_index  )
{
  clear_bit(UCSRB,TXB8);
  UDR = tx_buffer[tx_counter];
}
else
{
  tx_counter = 0;
  tx_buffer_index = 0;
  clear_bit(UCSRB,UDRIE);
};                         
}

void Uart_Send_Symbol(unsigned char symbol)
{
unsigned char sreg = 0;

sreg = SREG;
#asm("cli");
if( (tx_buffer_index == 0) && (check_bit(UCSRA,UDRE)) )
{
  clear_bit(UCSRB,TXB8);
  UDR = symbol;             
}
else
{
  tx_buffer[tx_buffer_index] = symbol;
};   
tx_buffer_index++; 
set_bit(UCSRB,UDRIE);     
SREG = sreg;
};

void init(void)
{   
UBRRH = ( (UBRR>>8) );
UBRRL = ( UBRR );

UCSRA = 0x00;
UCSRB = ( TXEN | RXEN | RXCIE );
UCSRC = ( UCSZ1 | UCSZ0 );

}

void Take_Data(void)
{
static unsigned char  sreg = 0 , data = 0 ;

sreg = SREG;
#asm("cli");
data = rx_buffer[rx_counter]; 
rx_counter++;
if( rx_buffer_index == rx_counter )
{
  clear_bit(global_flag,take_data_flag);
  rx_counter = 0;
  rx_buffer_index = 0;
};
SREG = sreg;

Uart_Send_Symbol(data);

}

void main(void)
{
init();
#asm("sei");
Uart_Send_Symbol('R');
do
{
  if( check_bit(global_flag,take_data_flag) )
  {
   Take_Data();
  }
}while(1);
}