/*This file is prepared for Doxygen automatic documentation generation.*/
/*! \file *********************************************************************
 *
 * \brief USART driver for AVR32 UC3.
 *
 * This file contains basic functions for the AVR32 USART, with support for all
 * modes, settings and clock speeds.
 *
 * - Compiler:           IAR EWAVR32 and GNU GCC for AVR32
 * - Supported devices:  All AVR32 devices with a USART module can be used.
 * - AppNote:
 *
 * \author               Atmel Corporation: http://www.atmel.com \n
 *                       Support email: avr32@atmel.com
 *
 ******************************************************************************/

/* Copyright (c) 2007, Atmel Corporation All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. The name of ATMEL may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY ATMEL ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY AND
 * SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


#ifndef _USART_H_
#define _USART_H_

#if __GNUC__
#  include <avr32/io.h>
#elif __ICCAVR32__
#  include <avr32/iouc3a0512.h>
#else
#  error Unknown compiler
#endif

#include "compiler.h"


/*! \name Return Values
 */
//! @{
#define USART_SUCCESS           0 //!< Successful completion.
#define USART_FAILURE          -1 //!< Failure because of some unspecified reason.
#define USART_INVALID_INPUT     1 //!< Input value out of range.
#define USART_INVALID_ARGUMENT -1 //!< Argument value out of range.
#define USART_TX_BUSY           2 //!< Transmitter was busy.
#define USART_RX_EMPTY          3 //!< Nothing was received.
#define USART_RX_ERROR          4 //!< Transmission error occurred.
#define USART_MODE_FAULT        5 //!< USART not in the appropriate mode.
//! @}

//! Default time-out value (number of attempts).
#define USART_DEFAULT_TIMEOUT   10000

/*! \name Parity Settings
 */
//! @{
#define USART_EVEN_PARITY       AVR32_USART_MR_PAR_EVEN   //!< Use even parity on character transmission.
#define USART_ODD_PARITY        AVR32_USART_MR_PAR_ODD    //!< Use odd parity on character transmission.
#define USART_SPACE_PARITY      AVR32_USART_MR_PAR_SPACE  //!< Use a space as parity bit.
#define USART_MARK_PARITY       AVR32_USART_MR_PAR_MARK   //!< Use a mark as parity bit.
#define USART_NO_PARITY         AVR32_USART_MR_PAR_NONE   //!< Don't use a parity bit.
#define USART_MULTIDROP_PARITY  AVR32_USART_MR_PAR_MULTI  //!< Parity bit is used to flag address characters.
//! @}

/*! \name Operating Modes
 */
//! @{
#define USART_MODE_NORMAL       AVR32_USART_MR_MODE_NORMAL      //!< Normal RS232 mode.
#define USART_MODE_RS485        AVR32_USART_MR_MODE_RS485       //!< RS485 mode.
#define USART_MODE_HW_HSH       AVR32_USART_MR_MODE_HARDWARE    //!< RS232 mode with hardware handshaking.
#define USART_MODE_MODEM        AVR32_USART_MR_MODE_MODEM       //!< Modem mode.
#define USART_MODE_ISO7816_T0   AVR32_USART_MR_MODE_ISO7816_T0  //!< ISO7816, T = 0 mode.
#define USART_MODE_ISO7816_T1   AVR32_USART_MR_MODE_ISO7816_T1  //!< ISO7816, T = 1 mode.
#define USART_MODE_IRDA         AVR32_USART_MR_MODE_IRDA        //!< IrDA mode.
#define USART_MODE_SW_HSH       AVR32_USART_MR_MODE_SOFTWARE    //!< RS232 mode with software handshaking.
//! @}

/*! \name Channel Modes
 */
//! @{
#define USART_NORMAL_CHMODE     AVR32_USART_MR_CHMODE_NORMAL      //!< Normal communication.
#define USART_AUTO_ECHO         AVR32_USART_MR_CHMODE_ECHO        //!< Echo data.
#define USART_LOCAL_LOOPBACK    AVR32_USART_MR_CHMODE_LOCAL_LOOP  //!< Local loopback.
#define USART_REMOTE_LOOPBACK   AVR32_USART_MR_CHMODE_REMOTE_LOOP //!< Remote loopback.
//! @}

/*! \name Stop Bits Settings
 */
//! @{
#define USART_1_STOPBIT         AVR32_USART_MR_NBSTOP_1   //!< Use 1 stop bit.
#define USART_1_5_STOPBITS      AVR32_USART_MR_NBSTOP_1_5 //!< Use 1.5 stop bits.
#define USART_2_STOPBITS        AVR32_USART_MR_NBSTOP_2   //!< Use 2 stop bits (for more, just give the number of bits).
//! @}


//! Input parameters when initializing RS232 and similar modes.
typedef struct
{
  //! Set baudrate of the USART.
  unsigned long baudrate;

  //! Number of bits to transmit as a character (5 to 9).
  unsigned char charlength;

  //! How to calculate the parity bit: \ref USART_EVEN_PARITY, \ref USART_ODD_PARITY,
  //! \ref USART_SPACE_PARITY, \ref USART_MARK_PARITY, \ref USART_NO_PARITY or
  //! \ref USART_MULTIDROP_PARITY.
  unsigned char paritytype;

  //! Number of stop bits between two characters: \ref USART_1_STOPBIT,
  //! \ref USART_1_5_STOPBITS, \ref USART_2_STOPBITS or any number from 3 to 257
  //! which will result in a time guard period of that length between characters.
  unsigned short stopbits;

  //! Run the channel in testmode: \ref USART_NORMAL_CHMODE, \ref USART_AUTO_ECHO,
  //! \ref USART_LOCAL_LOOPBACK or \ref USART_REMOTE_LOOPBACK.
  unsigned char channelmode;
} usart_options_t;

//! Input parameters when initializing ISO7816 modes.
typedef struct
{
  //! Set the frequency of the ISO7816 clock.
  unsigned long iso7816_hz;

  //! The number of ISO7816 clock ticks in every bit period (1 to 2047, 0 = disable clock).
  //! Bit rate = \ref iso7816_hz / \ref fidi_ratio.
  unsigned short fidi_ratio;

  //! Inhibit Non Acknowledge:\n
  //!   - 0: the NACK is generated;\n
  //!   - 1: the NACK is not generated.
  //!
  //! \note This bit will be used only in ISO7816 mode, protocol T = 0 receiver.
  int inhibit_nack;

  //! Disable successive NACKs.
  //! Successive parity errors are counted up to the value in the \ref max_iterations field.
  //! These parity errors generate a NACK on the ISO line. As soon as this value is reached,
  //! no addititional NACK is sent on the ISO line. The ITERATION flag is asserted.
  int dis_suc_nack;

  //! Max number of repetitions (0 to 7).
  unsigned char max_iterations;

  //! Bit order in transmitted characters:\n
  //!   - 0: LSB first;\n
  //!   - 1: MSB first.
  int bit_order;
} iso7816_options_t;


//------------------------------------------------------------------------------
/*! \name Initialization Functions
 */
//! @{

/*! \brief Resets the USART and disables TX and RX.
 *
 * \param usart Base address of the USART instance.
 */
extern void usart_reset(volatile avr32_usart_t *usart);

/*! \brief Sets up the USART to use the standard RS232 protocol.
 *
 * \param usart   Base address of the USART instance.
 * \param opt     Options needed to set up RS232 communication (see \ref usart_options_t).
 * \param pba_hz  USART module input clock frequency (PBA clock, Hz).
 *
 * \retval USART_SUCCESS        Mode successfully initialized.
 * \retval USART_INVALID_INPUT  One or more of the arguments is out of valid range.
 */
extern int usart_init_rs232(volatile avr32_usart_t *usart, const usart_options_t *opt, long pba_hz);

/*! \brief Sets up the USART to use hardware handshaking.
 *
 * \param usart   Base address of the USART instance.
 * \param opt     Options needed to set up RS232 communication (see \ref usart_options_t).
 * \param pba_hz  USART module input clock frequency (PBA clock, Hz).
 *
 * \retval USART_SUCCESS        Mode successfully initialized.
 * \retval USART_INVALID_INPUT  One or more of the arguments is out of valid range.
 *
 * \note \ref usart_init_rs232 does not need to be invoked before this function.
 */
extern int usart_init_hw_handshaking(volatile avr32_usart_t *usart, const usart_options_t *opt, long pba_hz);

/*! \brief Sets up the USART to use the IrDA protocol.