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/*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 and FAQ: http://support.atmel.no/
 *
 ******************************************************************************/
 
/* 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.
 */
 
 
#include "usart.h"
 
 
//------------------------------------------------------------------------------
/*! \name Private Functions
 */
//! @{
 
 
/*! \brief Checks if the USART is in multidrop mode.
 *
 * \param usart Base address of the USART instance.
 *
 * \return \c 1 if the USART is in multidrop mode, otherwise \c 0.
 */
#if __GNUC__
__attribute__((__always_inline__))
#endif
static __inline__ int usart_mode_is_multidrop(volatile avr32_usart_t *usart)
{
  return ((usart->mr >> AVR32_USART_MR_PAR_OFFSET) & AVR32_USART_MR_PAR_MULTI) == AVR32_USART_MR_PAR_MULTI;
}
 
 
/*! \brief Calculates a clock divider (\e CD) that gets the USART as close to a
 *         wanted baudrate as possible.
 *
 * \todo manage the FP fractal part to avoid big errors
 *
 * Baudrate calculation:
 * \f$ baudrate = \frac{Selected Clock}{16 \times CD} \f$ with 16x oversampling or
 * \f$ baudrate = \frac{Selected Clock}{8 \times CD} \f$ with 8x oversampling or
 * \f$ baudrate = \frac{Selected Clock}{CD} \f$ with SYNC bit set to allow high speed.
 *
 * \param usart     Base address of the USART instance.
 * \param baudrate  Wanted baudrate.
 * \param pba_hz    USART module input clock frequency (PBA clock, Hz).
 *
 * \retval USART_SUCCESS        Baudrate successfully initialized.
 * \retval USART_INVALID_INPUT  Wanted baudrate is impossible with given clock speed.
 */
 
static int usart_set_baudrate(volatile avr32_usart_t *usart, unsigned int baudrate, long pba_hz)
{
  // Clock divider.
  int cd;
 
  // Baudrate calculation.
  if (baudrate < pba_hz / 16)
  {
    // Use 16x oversampling, clear SYNC bit.
    usart->mr &=~ (AVR32_USART_MR_OVER_MASK | AVR32_USART_MR_SYNC_MASK);
    cd = (pba_hz + 8 * baudrate) / (16 * baudrate);
 
    if ((cd >65535)) return USART_INVALID_INPUT;
  }
  else if (baudrate < pba_hz / 8)
  {
    // Use 8x oversampling.
    usart->mr |= AVR32_USART_MR_OVER_MASK;
    // clear SYNC bit
    usart->mr &=~ AVR32_USART_MR_SYNC_MASK;
 
    cd = (pba_hz + 4 * baudrate) / (8 * baudrate);
 
    if ((cd < 1)||(cd >65535)) return USART_INVALID_INPUT;
  }
  else
  {
    // set SYNC to 1 
    usart->mr |= AVR32_USART_MR_SYNC_MASK;
    // use PBA/BaudRate
    cd = (pba_hz / baudrate);
  }
  usart->brgr = cd << AVR32_USART_BRGR_CD_OFFSET;
 
  return USART_SUCCESS;
}
 
//! @}
 
 
//------------------------------------------------------------------------------
/*! \name Initialization Functions
 */
//! @{
 
 
void usart_reset(volatile avr32_usart_t *usart)
{
  // Disable all USART interrupts.
  // Interrupts needed should be set explicitly on every reset.
  usart->idr = 0xFFFFFFFF;
 
  // Reset mode and other registers that could cause unpredictable behavior after reset.
  usart->mr = 0;
  usart->rtor = 0;
  usart->ttgr = 0;
 
  // Shutdown TX and RX (will be re-enabled when setup has successfully completed),
  // reset status bits and turn off DTR and RTS.
  usart->cr = AVR32_USART_CR_RSTRX_MASK   |
              AVR32_USART_CR_RSTTX_MASK   |
              AVR32_USART_CR_RSTSTA_MASK  |
              AVR32_USART_CR_RSTIT_MASK   |
              AVR32_USART_CR_RSTNACK_MASK |
              AVR32_USART_CR_DTRDIS_MASK  |
              AVR32_USART_CR_RTSDIS_MASK;
}
 
 
int usart_init_rs232(volatile avr32_usart_t *usart, const usart_options_t *opt, long pba_hz)
{
  // Reset the USART and shutdown TX and RX.
  usart_reset(usart);
 
  // Check input values.
  if (!opt) // Null pointer.
    return USART_INVALID_INPUT;
  if (opt->charlength < 5 || opt->charlength > 9 ||
      opt->paritytype > 7 ||
      opt->stopbits > 2 + 255 ||
      opt->channelmode > 3)
    return USART_INVALID_INPUT;
 
  if (usart_set_baudrate(usart, opt->baudrate, pba_hz) == USART_INVALID_INPUT)
    return USART_INVALID_INPUT;
 
  if (opt->charlength == 9)
  {
    // Character length set to 9 bits. MODE9 dominates CHRL.
    usart->mr |= AVR32_USART_MR_MODE9_MASK;
  }
  else
  {
    // CHRL gives the character length (- 5) when MODE9 = 0.
    usart->mr |= (opt->charlength - 5) << AVR32_USART_MR_CHRL_OFFSET;
  }
 
  usart->mr |= (opt->channelmode << AVR32_USART_MR_CHMODE_OFFSET) |
               (opt->paritytype << AVR32_USART_MR_PAR_OFFSET);
 
  if (opt->stopbits > USART_2_STOPBITS)
  {
    // Set two stop bits
    usart->mr |= AVR32_USART_MR_NBSTOP_2 << AVR32_USART_MR_NBSTOP_OFFSET;
    // and a timeguard period gives the rest.
    usart->ttgr = opt->stopbits - USART_2_STOPBITS;
  }
  else
    // Insert 1, 1.5 or 2 stop bits.
    usart->mr |= opt->stopbits << AVR32_USART_MR_NBSTOP_OFFSET;
 
  // Setup complete; enable communication.
  // Enable input and output.
  usart->cr |= AVR32_USART_CR_TXEN_MASK |
               AVR32_USART_CR_RXEN_MASK;
 
  return USART_SUCCESS;
}
 
 
int usart_init_hw_handshaking(volatile avr32_usart_t *usart, const usart_options_t *opt, long pba_hz)
{
  // First: Setup standard RS232.
  if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)
    return USART_INVALID_INPUT;
 
  // Clear previous mode.
  usart->mr &= ~AVR32_USART_MR_MODE_MASK;
  // Hardware handshaking.
  usart->mr |= USART_MODE_HW_HSH << AVR32_USART_MR_MODE_OFFSET;
 
  return USART_SUCCESS;
}
 
 
int usart_init_IrDA(volatile avr32_usart_t *usart, const usart_options_t *opt,
                    long pba_hz, unsigned char irda_filter)
{
  // First: Setup standard RS232.
  if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)
    return USART_INVALID_INPUT;
 
  // Set IrDA counter.
  usart->ifr = irda_filter;
 
  // Activate "low-pass filtering" of input.
  usart->mr |= AVR32_USART_MR_FILTER_MASK;
 
  return USART_SUCCESS;
}
 
 
int usart_init_modem(volatile avr32_usart_t *usart, const usart_options_t *opt, long pba_hz)
{
  // First: Setup standard RS232.
  if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)
    return USART_INVALID_INPUT;
 
  // Clear previous mode.
  usart->mr &= ~AVR32_USART_MR_MODE_MASK;
  // Set modem mode.
  usart->mr |= USART_MODE_MODEM << AVR32_USART_MR_MODE_OFFSET;
 
  return USART_SUCCESS;
}
 
 
int usart_init_rs485(volatile avr32_usart_t *usart, const usart_options_t *opt, long pba_hz)
{
  // First: Setup standard RS232.
  if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)
    return USART_INVALID_INPUT;
 
  // Clear previous mode.
  usart->mr &= ~AVR32_USART_MR_MODE_MASK;
  // Set RS485 mode.
  usart->mr |= USART_MODE_RS485 << AVR32_USART_MR_MODE_OFFSET;
 
  return USART_SUCCESS;
}
 
 
int usart_init_iso7816(volatile avr32_usart_t *usart, const iso7816_options_t *opt, int t, long pba_hz)
{
  // Reset the USART and shutdown TX and RX.
  usart_reset(usart);
 
  // Check input values.
  if (!opt) // Null pointer.
    return USART_INVALID_INPUT;
 
  if (t == 0)
  {
    // Set USART mode to ISO7816, T=0.
    // The T=0 protocol always uses 2 stop bits.
    usart->mr = (USART_MODE_ISO7816_T0 << AVR32_USART_MR_MODE_OFFSET) |
                (AVR32_USART_MR_NBSTOP_2 << AVR32_USART_MR_NBSTOP_OFFSET) |
                (opt->bit_order << AVR32_USART_MR_MSBF_OFFSET); // Allow MSBF in T=0.
  }
  else if (t == 1)
  {
    // Only LSB first in the T=1 protocol.
    // max_iterations field is only used in T=0 mode.
    if (opt->bit_order != 0 ||
        opt->max_iterations != 0)
      return USART_INVALID_INPUT;
    // Set USART mode to ISO7816, T=1.
    // The T=1 protocol always uses 1 stop bit.
    usart->mr = (USART_MODE_ISO7816_T1 << AVR32_USART_MR_MODE_OFFSET) |
                (AVR32_USART_MR_NBSTOP_1 << AVR32_USART_MR_NBSTOP_OFFSET);
  }
  else
    return USART_INVALID_INPUT;
 
  if (usart_set_baudrate(usart, opt->iso7816_hz, pba_hz) == USART_INVALID_INPUT)
    return USART_INVALID_INPUT;
 
  // Set FIDI register: bit rate = selected clock/FI_DI_ratio/16.
  usart->fidi = opt->fidi_ratio;
  // Set ISO7816 spesific options in the MODE register.
  usart->mr |= (opt->inhibit_nack << AVR32_USART_MR_INACK_OFFSET) |
               (opt->dis_suc_nack << AVR32_USART_MR_DSNACK_OFFSET) |
               (opt->max_iterations << AVR32_USART_MR_MAX_ITERATION_OFFSET) |
               AVR32_USART_MR_CLKO_MASK;  // Enable clock output.
 
  // Setup complete; enable input.
  // Leave TX disabled for now.
  usart->cr |= AVR32_USART_CR_RXEN_MASK;
 
  return USART_SUCCESS;
}
//! @}
 
 
//------------------------------------------------------------------------------
/*! \name Transmit/Receive Functions
 */
//! @{
 
 
int usart_send_address(volatile avr32_usart_t *usart, int address)
{
  // Check if USART is in multidrop / RS485 mode.
  if (!usart_mode_is_multidrop(usart)) return USART_MODE_FAULT;
 
  // Prepare to send an address.
  usart->cr |= AVR32_USART_CR_SENDA_MASK;
 
  // Write the address to TX.
  usart_bw_write_char(usart, address);
 
  return USART_SUCCESS;
}
 
 
int usart_write_char(volatile avr32_usart_t *usart, int c)
{
  if (usart->csr & AVR32_USART_CSR_TXRDY_MASK)
  {
    usart->thr = c;
    return USART_SUCCESS;
  }
  else
    return USART_TX_BUSY;
}
 
 
int usart_putchar(volatile avr32_usart_t *usart, int c)
{
  int timeout = USART_DEFAULT_TIMEOUT;
 
  if (c == '\n')
  {
    do
    {
      if (!timeout--) return USART_FAILURE;
    } while (usart_write_char(usart, '\r') != USART_SUCCESS);
 
    timeout = USART_DEFAULT_TIMEOUT;
  }
 
  do
  {
    if (!timeout--) return USART_FAILURE;
  } while (usart_write_char(usart, c) != USART_SUCCESS);
 
  return USART_SUCCESS;
}
 
 
int usart_read_char(volatile avr32_usart_t *usart, int *c)
{
  // Check for errors: frame, parity and overrun. In RS485 mode, a parity error
  // would mean that an address char has been received.
  if (usart->csr & (AVR32_USART_CSR_OVRE_MASK |
                    AVR32_USART_CSR_FRAME_MASK |
                    AVR32_USART_CSR_PARE_MASK))
    return USART_RX_ERROR;
 
  // No error; if we really did receive a char, read it and return SUCCESS.
  if (usart->csr & AVR32_USART_CSR_RXRDY_MASK)
  {
    *c = (unsigned short)usart->rhr;
    return USART_SUCCESS;
  }
  else
    return USART_RX_EMPTY;
}
 
 
int usart_getchar(volatile avr32_usart_t *usart)
{
  int c, ret;
 
  while ((ret = usart_read_char(usart, &c)) == USART_RX_EMPTY);
 
  if (ret == USART_RX_ERROR)
    return USART_FAILURE;
 
  return c;
}
 
 
void usart_write_line(volatile avr32_usart_t *usart, const char *string)
{
  while (*string != '\0')
    usart_putchar(usart, *string++);
}
 
 
int usart_get_echo_line(volatile avr32_usart_t *usart)
{
  int rx_char;
  int retval = USART_SUCCESS;
 
  while (1)
  {
    rx_char = usart_getchar(usart);
    if (rx_char == USART_FAILURE)
    {
      usart_write_line(usart, "Error!!!\n");
      break;
    }
    if (rx_char == '\x03')
    {
      retval = USART_FAILURE;
      break;
    }
    usart_putchar(usart, rx_char);
    if (rx_char == '\r')
    {
      usart_putchar(usart, '\n');
      break;
    }
  }
 
  return retval;
}
 
 
//! @}

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[/] [openrisc/] [trunk/] [rtos/] [freertos-6.1.1/] [Demo/] [lwIP_AVR32_UC3/] [DRIVERS/] [USART/] [usart.c] - Blame information for rev 609

Line No.	Rev	Author	Line
1	583	jeremybenn	`/This file is prepared for Doxygen automatic documentation generation./`
2			`/! \file ********************************************************************`
3			`*`
4			`* \brief USART driver for AVR32 UC3.`
5			`*`
6			`* This file contains basic functions for the AVR32 USART, with support for all`
7			`* modes, settings and clock speeds.`
8			`*`
9			`* - Compiler: IAR EWAVR32 and GNU GCC for AVR32`
10			`* - Supported devices: All AVR32 devices with a USART module can be used.`
11			`* - AppNote:`
12			`*`
13			`* \author Atmel Corporation: http://www.atmel.com \n`
14			`* Support and FAQ: http://support.atmel.no/`
15			`*`
16			`******************************************************************************/`
17
18			`/* Copyright (c) 2007, Atmel Corporation All rights reserved.`
19			`*`
20			`* Redistribution and use in source and binary forms, with or without`
21			`* modification, are permitted provided that the following conditions are met:`
22			`*`
23			`* 1. Redistributions of source code must retain the above copyright notice,`
24			`* this list of conditions and the following disclaimer.`
25			`*`
26			`* 2. Redistributions in binary form must reproduce the above copyright notice,`
27			`* this list of conditions and the following disclaimer in the documentation`
28			`* and/or other materials provided with the distribution.`
29			`*`
30			`* 3. The name of ATMEL may not be used to endorse or promote products derived`
31			`* from this software without specific prior written permission.`
32			`*`
33			* THIS SOFTWARE IS PROVIDED BY ATMEL ``AS IS'' AND ANY EXPRESS OR IMPLIED
34			`* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF`
35			`* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY AND`
36			`* SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT,`
37			`* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES`
38			`* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;`
39			`* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND`
40			`* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT`
41			`* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF`
42			`* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.`
43			`*/`
44
45
46			`#include "usart.h"`
47
48
49			`//------------------------------------------------------------------------------`
50			`/*! \name Private Functions`
51			`*/`
52			`//! @{`
53
54
55			`/*! \brief Checks if the USART is in multidrop mode.`
56			`*`
57			`* \param usart Base address of the USART instance.`
58			`*`
59			`* \return \c 1 if the USART is in multidrop mode, otherwise \c 0.`
60			`*/`
61			`#if __GNUC__`
62			`__attribute__((__always_inline__))`
63			`#endif`
64			`static __inline__ int usart_mode_is_multidrop(volatile avr32_usart_t *usart)`
65			`{`
66			`return ((usart->mr >> AVR32_USART_MR_PAR_OFFSET) & AVR32_USART_MR_PAR_MULTI) == AVR32_USART_MR_PAR_MULTI;`
67			`}`
68
69
70			`/*! \brief Calculates a clock divider (\e CD) that gets the USART as close to a`
71			`* wanted baudrate as possible.`
72			`*`
73			`* \todo manage the FP fractal part to avoid big errors`
74			`*`
75			`* Baudrate calculation:`
76			`* \f$ baudrate = \frac{Selected Clock}{16 \times CD} \f$ with 16x oversampling or`
77			`* \f$ baudrate = \frac{Selected Clock}{8 \times CD} \f$ with 8x oversampling or`
78			`* \f$ baudrate = \frac{Selected Clock}{CD} \f$ with SYNC bit set to allow high speed.`
79			`*`
80			`* \param usart Base address of the USART instance.`
81			`* \param baudrate Wanted baudrate.`
82			`* \param pba_hz USART module input clock frequency (PBA clock, Hz).`
83			`*`
84			`* \retval USART_SUCCESS Baudrate successfully initialized.`
85			`* \retval USART_INVALID_INPUT Wanted baudrate is impossible with given clock speed.`
86			`*/`
87
88			`static int usart_set_baudrate(volatile avr32_usart_t *usart, unsigned int baudrate, long pba_hz)`
89			`{`
90			`// Clock divider.`
91			`int cd;`
92
93			`// Baudrate calculation.`
94			`if (baudrate < pba_hz / 16)`
95			`{`
96			`// Use 16x oversampling, clear SYNC bit.`
97			`usart->mr &=~ (AVR32_USART_MR_OVER_MASK \| AVR32_USART_MR_SYNC_MASK);`
98			`cd = (pba_hz + 8 * baudrate) / (16 * baudrate);`
99
100			`if ((cd >65535)) return USART_INVALID_INPUT;`
101			`}`
102			`else if (baudrate < pba_hz / 8)`
103			`{`
104			`// Use 8x oversampling.`
105			`usart->mr \|= AVR32_USART_MR_OVER_MASK;`
106			`// clear SYNC bit`
107			`usart->mr &=~ AVR32_USART_MR_SYNC_MASK;`
108
109			`cd = (pba_hz + 4 * baudrate) / (8 * baudrate);`
110
111			`if ((cd < 1)\|\|(cd >65535)) return USART_INVALID_INPUT;`
112			`}`
113			`else`
114			`{`
115			`// set SYNC to 1`
116			`usart->mr \|= AVR32_USART_MR_SYNC_MASK;`
117			`// use PBA/BaudRate`
118			`cd = (pba_hz / baudrate);`
119			`}`
120			`usart->brgr = cd << AVR32_USART_BRGR_CD_OFFSET;`
121
122			`return USART_SUCCESS;`
123			`}`
124
125			`//! @}`
126
127
128			`//------------------------------------------------------------------------------`
129			`/*! \name Initialization Functions`
130			`*/`
131			`//! @{`
132
133
134			`void usart_reset(volatile avr32_usart_t *usart)`
135			`{`
136			`// Disable all USART interrupts.`
137			`// Interrupts needed should be set explicitly on every reset.`
138			`usart->idr = 0xFFFFFFFF;`
139
140			`// Reset mode and other registers that could cause unpredictable behavior after reset.`
141			`usart->mr = 0;`
142			`usart->rtor = 0;`
143			`usart->ttgr = 0;`
144
145			`// Shutdown TX and RX (will be re-enabled when setup has successfully completed),`
146			`// reset status bits and turn off DTR and RTS.`
147			`usart->cr = AVR32_USART_CR_RSTRX_MASK \|`
148			`AVR32_USART_CR_RSTTX_MASK \|`
149			`AVR32_USART_CR_RSTSTA_MASK \|`
150			`AVR32_USART_CR_RSTIT_MASK \|`
151			`AVR32_USART_CR_RSTNACK_MASK \|`
152			`AVR32_USART_CR_DTRDIS_MASK \|`
153			`AVR32_USART_CR_RTSDIS_MASK;`
154			`}`
155
156
157			`int usart_init_rs232(volatile avr32_usart_t usart, const usart_options_t opt, long pba_hz)`
158			`{`
159			`// Reset the USART and shutdown TX and RX.`
160			`usart_reset(usart);`
161
162			`// Check input values.`
163			`if (!opt) // Null pointer.`
164			`return USART_INVALID_INPUT;`
165			`if (opt->charlength < 5 \|\| opt->charlength > 9 \|\|`
166			`opt->paritytype > 7 \|\|`
167			`opt->stopbits > 2 + 255 \|\|`
168			`opt->channelmode > 3)`
169			`return USART_INVALID_INPUT;`
170
171			`if (usart_set_baudrate(usart, opt->baudrate, pba_hz) == USART_INVALID_INPUT)`
172			`return USART_INVALID_INPUT;`
173
174			`if (opt->charlength == 9)`
175			`{`
176			`// Character length set to 9 bits. MODE9 dominates CHRL.`
177			`usart->mr \|= AVR32_USART_MR_MODE9_MASK;`
178			`}`
179			`else`
180			`{`
181			`// CHRL gives the character length (- 5) when MODE9 = 0.`
182			`usart->mr \|= (opt->charlength - 5) << AVR32_USART_MR_CHRL_OFFSET;`
183			`}`
184
185			`usart->mr \|= (opt->channelmode << AVR32_USART_MR_CHMODE_OFFSET) \|`
186			`(opt->paritytype << AVR32_USART_MR_PAR_OFFSET);`
187
188			`if (opt->stopbits > USART_2_STOPBITS)`
189			`{`
190			`// Set two stop bits`
191			`usart->mr \|= AVR32_USART_MR_NBSTOP_2 << AVR32_USART_MR_NBSTOP_OFFSET;`
192			`// and a timeguard period gives the rest.`
193			`usart->ttgr = opt->stopbits - USART_2_STOPBITS;`
194			`}`
195			`else`
196			`// Insert 1, 1.5 or 2 stop bits.`
197			`usart->mr \|= opt->stopbits << AVR32_USART_MR_NBSTOP_OFFSET;`
198
199			`// Setup complete; enable communication.`
200			`// Enable input and output.`
201			`usart->cr \|= AVR32_USART_CR_TXEN_MASK \|`
202			`AVR32_USART_CR_RXEN_MASK;`
203
204			`return USART_SUCCESS;`
205			`}`
206
207
208			`int usart_init_hw_handshaking(volatile avr32_usart_t usart, const usart_options_t opt, long pba_hz)`
209			`{`
210			`// First: Setup standard RS232.`
211			`if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)`
212			`return USART_INVALID_INPUT;`
213
214			`// Clear previous mode.`
215			`usart->mr &= ~AVR32_USART_MR_MODE_MASK;`
216			`// Hardware handshaking.`
217			`usart->mr \|= USART_MODE_HW_HSH << AVR32_USART_MR_MODE_OFFSET;`
218
219			`return USART_SUCCESS;`
220			`}`
221
222
223			`int usart_init_IrDA(volatile avr32_usart_t usart, const usart_options_t opt,`
224			`long pba_hz, unsigned char irda_filter)`
225			`{`
226			`// First: Setup standard RS232.`
227			`if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)`
228			`return USART_INVALID_INPUT;`
229
230			`// Set IrDA counter.`
231			`usart->ifr = irda_filter;`
232
233			`// Activate "low-pass filtering" of input.`
234			`usart->mr \|= AVR32_USART_MR_FILTER_MASK;`
235
236			`return USART_SUCCESS;`
237			`}`
238
239
240			`int usart_init_modem(volatile avr32_usart_t usart, const usart_options_t opt, long pba_hz)`
241			`{`
242			`// First: Setup standard RS232.`
243			`if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)`
244			`return USART_INVALID_INPUT;`
245
246			`// Clear previous mode.`
247			`usart->mr &= ~AVR32_USART_MR_MODE_MASK;`
248			`// Set modem mode.`
249			`usart->mr \|= USART_MODE_MODEM << AVR32_USART_MR_MODE_OFFSET;`
250
251			`return USART_SUCCESS;`
252			`}`
253
254
255			`int usart_init_rs485(volatile avr32_usart_t usart, const usart_options_t opt, long pba_hz)`
256			`{`
257			`// First: Setup standard RS232.`
258			`if (usart_init_rs232(usart, opt, pba_hz) == USART_INVALID_INPUT)`
259			`return USART_INVALID_INPUT;`
260
261			`// Clear previous mode.`
262			`usart->mr &= ~AVR32_USART_MR_MODE_MASK;`
263			`// Set RS485 mode.`
264			`usart->mr \|= USART_MODE_RS485 << AVR32_USART_MR_MODE_OFFSET;`
265
266			`return USART_SUCCESS;`
267			`}`
268
269
270			`int usart_init_iso7816(volatile avr32_usart_t usart, const iso7816_options_t opt, int t, long pba_hz)`
271			`{`
272			`// Reset the USART and shutdown TX and RX.`
273			`usart_reset(usart);`
274
275			`// Check input values.`
276			`if (!opt) // Null pointer.`
277			`return USART_INVALID_INPUT;`
278
279			`if (t == 0)`
280			`{`
281			`// Set USART mode to ISO7816, T=0.`
282			`// The T=0 protocol always uses 2 stop bits.`
283			`usart->mr = (USART_MODE_ISO7816_T0 << AVR32_USART_MR_MODE_OFFSET) \|`
284			`(AVR32_USART_MR_NBSTOP_2 << AVR32_USART_MR_NBSTOP_OFFSET) \|`
285			`(opt->bit_order << AVR32_USART_MR_MSBF_OFFSET); // Allow MSBF in T=0.`
286			`}`
287			`else if (t == 1)`
288			`{`
289			`// Only LSB first in the T=1 protocol.`
290			`// max_iterations field is only used in T=0 mode.`
291			`if (opt->bit_order != 0 \|\|`
292			`opt->max_iterations != 0)`
293			`return USART_INVALID_INPUT;`
294			`// Set USART mode to ISO7816, T=1.`
295			`// The T=1 protocol always uses 1 stop bit.`
296			`usart->mr = (USART_MODE_ISO7816_T1 << AVR32_USART_MR_MODE_OFFSET) \|`
297			`(AVR32_USART_MR_NBSTOP_1 << AVR32_USART_MR_NBSTOP_OFFSET);`
298			`}`
299			`else`
300			`return USART_INVALID_INPUT;`
301
302			`if (usart_set_baudrate(usart, opt->iso7816_hz, pba_hz) == USART_INVALID_INPUT)`
303			`return USART_INVALID_INPUT;`
304
305			`// Set FIDI register: bit rate = selected clock/FI_DI_ratio/16.`
306			`usart->fidi = opt->fidi_ratio;`
307			`// Set ISO7816 spesific options in the MODE register.`
308			`usart->mr \|= (opt->inhibit_nack << AVR32_USART_MR_INACK_OFFSET) \|`
309			`(opt->dis_suc_nack << AVR32_USART_MR_DSNACK_OFFSET) \|`
310			`(opt->max_iterations << AVR32_USART_MR_MAX_ITERATION_OFFSET) \|`
311			`AVR32_USART_MR_CLKO_MASK; // Enable clock output.`
312
313			`// Setup complete; enable input.`
314			`// Leave TX disabled for now.`
315			`usart->cr \|= AVR32_USART_CR_RXEN_MASK;`
316
317			`return USART_SUCCESS;`
318			`}`
319			`//! @}`
320
321
322			`//------------------------------------------------------------------------------`
323			`/*! \name Transmit/Receive Functions`
324			`*/`
325			`//! @{`
326
327
328			`int usart_send_address(volatile avr32_usart_t *usart, int address)`
329			`{`
330			`// Check if USART is in multidrop / RS485 mode.`
331			`if (!usart_mode_is_multidrop(usart)) return USART_MODE_FAULT;`
332
333			`// Prepare to send an address.`
334			`usart->cr \|= AVR32_USART_CR_SENDA_MASK;`
335
336			`// Write the address to TX.`
337			`usart_bw_write_char(usart, address);`
338
339			`return USART_SUCCESS;`
340			`}`
341
342
343			`int usart_write_char(volatile avr32_usart_t *usart, int c)`
344			`{`
345			`if (usart->csr & AVR32_USART_CSR_TXRDY_MASK)`
346			`{`
347			`usart->thr = c;`
348			`return USART_SUCCESS;`
349			`}`
350			`else`
351			`return USART_TX_BUSY;`
352			`}`
353
354
355			`int usart_putchar(volatile avr32_usart_t *usart, int c)`
356			`{`
357			`int timeout = USART_DEFAULT_TIMEOUT;`
358
359			`if (c == '\n')`
360			`{`
361			`do`
362			`{`
363			`if (!timeout--) return USART_FAILURE;`
364			`} while (usart_write_char(usart, '\r') != USART_SUCCESS);`
365
366			`timeout = USART_DEFAULT_TIMEOUT;`
367			`}`
368
369			`do`
370			`{`
371			`if (!timeout--) return USART_FAILURE;`
372			`} while (usart_write_char(usart, c) != USART_SUCCESS);`
373
374			`return USART_SUCCESS;`
375			`}`
376
377
378			`int usart_read_char(volatile avr32_usart_t usart, int c)`
379			`{`
380			`// Check for errors: frame, parity and overrun. In RS485 mode, a parity error`
381			`// would mean that an address char has been received.`
382			`if (usart->csr & (AVR32_USART_CSR_OVRE_MASK \|`
383			`AVR32_USART_CSR_FRAME_MASK \|`
384			`AVR32_USART_CSR_PARE_MASK))`
385			`return USART_RX_ERROR;`
386
387			`// No error; if we really did receive a char, read it and return SUCCESS.`
388			`if (usart->csr & AVR32_USART_CSR_RXRDY_MASK)`
389			`{`
390			`*c = (unsigned short)usart->rhr;`
391			`return USART_SUCCESS;`
392			`}`
393			`else`
394			`return USART_RX_EMPTY;`
395			`}`
396
397
398			`int usart_getchar(volatile avr32_usart_t *usart)`
399			`{`
400			`int c, ret;`
401
402			`while ((ret = usart_read_char(usart, &c)) == USART_RX_EMPTY);`
403
404			`if (ret == USART_RX_ERROR)`
405			`return USART_FAILURE;`
406
407			`return c;`
408			`}`
409
410
411			`void usart_write_line(volatile avr32_usart_t usart, const char string)`
412			`{`
413			`while (*string != '\0')`
414			`usart_putchar(usart, *string++);`
415			`}`
416
417
418			`int usart_get_echo_line(volatile avr32_usart_t *usart)`
419			`{`
420			`int rx_char;`
421			`int retval = USART_SUCCESS;`
422
423			`while (1)`
424			`{`
425			`rx_char = usart_getchar(usart);`
426			`if (rx_char == USART_FAILURE)`
427			`{`
428			`usart_write_line(usart, "Error!!!\n");`
429			`break;`
430			`}`
431			`if (rx_char == '\x03')`
432			`{`
433			`retval = USART_FAILURE;`
434			`break;`
435			`}`
436			`usart_putchar(usart, rx_char);`
437			`if (rx_char == '\r')`
438			`{`
439			`usart_putchar(usart, '\n');`
440			`break;`
441			`}`
442			`}`
443
444			`return retval;`
445			`}`
446
447
448			`//! @}`