Tooltron

/********

 * This file is part of Tooltron.

 *

 * Tooltron is free software: you can redistribute it and/or modify

 * it under the terms of the Lesser GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * Tooltron is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * Lesser GNU General Public License for more details.

 * You should have received a copy of the Lesser GNU General Public License

 * along with Tooltron.  If not, see <http://www.gnu.org/licenses/>.

 *

 * Copyright 2009 Kevin Woo <kwoo@2ndt.com>

 *

 ********/

/** @file rs485_int.h

 *

 *        @brief Initializes UART functions using the UART hardware module

 *

 *        @author Kevin Woo (kwoo)

 */

#ifndef UART_H

#define UART_H

#include <avr/io.h>

#include <avr/interrupt.h>

#include <stdint.h>

/** **/

#define RS485_TX_OFF 0

#define RS485_TX_ON 1

/** @brief RX Pin for the UART **/

#define RX                _BV(PORTD0)

#define TX                _BV(PORTD1)

#define TX_EN        _BV(PORTD2)

/**

 * @brief This si the value to pass into UBRR tos et the baudrate.

 * @note this assumes an 8MHz system clock

 */

#define BAUD9600    51

/** @brief The most recently received byte **/

extern uint8_t received_byte;

/** @brief If the value in received_byte has been read or not **/

extern uint8_t byte_ready;

/** @brief Initializes the UART registers and sets it to the buad rate

 *         which msut be the value that is defined in the datasheet

 *         for any particular speed (ie: 51 -> 9600bps)

 **/

void rs485_init(uint16_t baud);

/** @brief Gets latest byte and returns it in output_byte. If the byte

 *         was already read, returns -1 otherwise it returns 0

 **/

int8_t rs485_get_byte(uint8_t *output_byte);

/** @brief Sends a character array of size size. If we are currently

 *         transmitting it will block until the the current transmit

 *         is done.

 **/

void rs485_send_byte(uint8_t data);

void rs485_toggle_transmit(uint8_t state);

#endif