uart.cpp 835 Bytes
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#include "uart.hpp"

#include "servos.hpp"
#include "command.h"

#include <avr/io.h>
#include <avr/interrupt.h>

void initUart()
{
    cli();
    
    UCSR0A = (1 << U2X0);  // double transmission speed
    UCSR0B = (1 << RXCIE0) // enable RX complete interrupt
           | (1 << UDRIE0) // enable data register empty interrupt
           | (1 << RXEN0)  // enable receiver
           | (1 << TXEN0); // enable transmitter
    UCSR0C = (0 << UMSEL01) | (0 << UMSEL00) // asynchronous USART
           | (0 << UPM01) | (0 << UPM00)     // no parity bit
           | (0 << USBS0)                    // 1 stop bit
           | (1 << UCSZ01) | (1 << UCSZ00);  // 8 data bits
    
    UBRR0 = 16; // 115.2k baud rate
    
    sei();
}

ISR(USART_RX_vect)
{
    uart_add_ch(UDR0);
}

ISR(USART_UDRE_vect)
{
    // nothing to do right now
}