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/**
* \file
*
* \brief Universal Synchronous Asynchronous Receiver Transmitter (USART) driver
* for SAM.
*
* Copyright (c) 2011-2015 Atmel Corporation. All rights reserved.
*
* \asf_license_start
*
* \page License
*
* 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.
*
* 4. This software may only be redistributed and used in connection with an
* Atmel microcontroller product.
*
* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT 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.
*
* \asf_license_stop
*
*/
/*
* Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
*/
#ifndef USART_H_INCLUDED
#define USART_H_INCLUDED
#include "compiler.h"
/**
* \defgroup group_sam_drivers_usart Universal Synchronous Asynchronous Receiver
* Transmitter (USART).
*
* See \ref sam_usart_quickstart.
*
* This is a low-level driver implementation for the SAM Universal
* Synchronous/Asynchronous Receiver/Transmitter.
*
* @{
*/
/// @cond 0
/**INDENT-OFF**/
#ifdef __cplusplus
extern "C" {
#endif
/**INDENT-ON**/
/// @endcond
/** Clock phase. */
#define SPI_CPHA (1 << 0)
/** Clock polarity. */
#define SPI_CPOL (1 << 1)
/** SPI mode definition. */
#define SPI_MODE_0 0
#define SPI_MODE_1 (SPI_CPHA)
#define SPI_MODE_2 (SPI_CPOL)
#define SPI_MODE_3 (SPI_CPOL | SPI_CPHA)
/**micro definition for LIN mode of SAMV71*/
#if (SAMV71 || SAMV70 || SAME70 || SAMS70)
#define US_MR_USART_MODE_LIN_MASTER 0x0A
#define US_MR_USART_MODE_LIN_SLAVE 0x0B
#endif
/* Input parameters when initializing RS232 and similar modes. */
typedef struct {
/* Set baud rate of the USART (unused in slave modes). */
uint32_t baudrate;
/*
* Number of bits, which should be one of the following: US_MR_CHRL_5_BIT,
* US_MR_CHRL_6_BIT, US_MR_CHRL_7_BIT, US_MR_CHRL_8_BIT or
* US_MR_MODE9.
*/
uint32_t char_length;
/*
* Parity type, which should be one of the following: US_MR_PAR_EVEN,
* US_MR_PAR_ODD, US_MR_PAR_SPACE, US_MR_PAR_MARK, US_MR_PAR_NO
* or US_MR_PAR_MULTIDROP.
*/
uint32_t parity_type;
/*
* Number of stop bits between two characters: US_MR_NBSTOP_1_BIT,
* US_MR_NBSTOP_1_5_BIT, US_MR_NBSTOP_2_BIT.
* \note US_MR_NBSTOP_1_5_BIT is supported in asynchronous modes only.
*/
uint32_t stop_bits;
/*
* Run the channel in test mode, which should be one of following:
* US_MR_CHMODE_NORMAL, US_MR_CHMODE_AUTOMATIC,
* US_MR_CHMODE_LOCAL_LOOPBACK, US_MR_CHMODE_REMOTE_LOOPBACK.
*/
uint32_t channel_mode;
/* Filter of IrDA mode, useless in other modes. */
uint32_t irda_filter;
} sam_usart_opt_t;
/* Input parameters when initializing ISO7816 mode. */
typedef struct {
/* Set the frequency of the ISO7816 clock. */
uint32_t iso7816_hz;
/*
* The number of ISO7816 clock ticks in every bit period (1 to 2047,
* 0 = disable clock). Baudrate rate = iso7816_hz / fidi_ratio.
*/
uint32_t fidi_ratio;
/*
* How to calculate the parity bit: US_MR_PAR_EVEN for normal mode or
* US_MR_PAR_ODD for inverse mode.
*/
uint32_t parity_type;
/*
* Inhibit Non Acknowledge:
* - 0: the NACK is generated;
* - 1: the NACK is not generated.
*
* \note This bit will be used only in ISO7816 mode, protocol T = 0
* receiver.
*/
uint32_t inhibit_nack;
/*
* Disable successive NACKs.
* - 0: NACK is sent on the ISO line as soon as a parity error occurs
* in the received character. Successive parity errors are counted up to
* the value in the max_iterations field. These parity errors generate
* a NACK on the ISO line. As soon as this value is reached, no additional
* NACK is sent on the ISO line. The ITERATION flag is asserted.
*/
uint32_t dis_suc_nack;
/* Max number of repetitions (0 to 7). */
uint32_t max_iterations;
/*
* Bit order in transmitted characters:
* - 0: LSB first;
* - 1: MSB first.
*/
uint32_t bit_order;
/*
* Which protocol is used:
* - 0: T = 0;
* - 1: T = 1.
*/
uint32_t protocol_type;
} usart_iso7816_opt_t;
/* Input parameters when initializing SPI mode. */
typedef struct {
/* Set the frequency of the SPI clock (unused in slave mode). */
uint32_t baudrate;
/*
* Number of bits, which should be one of the following: US_MR_CHRL_5_BIT,
* US_MR_CHRL_6_BIT, US_MR_CHRL_7_BIT, US_MR_CHRL_8_BIT or
* US_MR_MODE9.
*/
uint32_t char_length;
/*
* Which SPI mode to use, which should be one of the following:
* SPI_MODE_0, SPI_MODE_1, SPI_MODE_2, SPI_MODE_3.
*/
uint32_t spi_mode;
/*
* Run the channel in test mode, which should be one of following:
* US_MR_CHMODE_NORMAL, US_MR_CHMODE_AUTOMATIC,
* US_MR_CHMODE_LOCAL_LOOPBACK, US_MR_CHMODE_REMOTE_LOOPBACK.
*/
uint32_t channel_mode;
} usart_spi_opt_t;
void usart_reset(Usart *p_usart);
uint32_t usart_set_async_baudrate(Usart *p_usart,
uint32_t baudrate, uint32_t ul_mck);
uint32_t usart_init_rs232(Usart *p_usart,
const sam_usart_opt_t *p_usart_opt, uint32_t ul_mck);
uint32_t usart_init_hw_handshaking(Usart *p_usart,
const sam_usart_opt_t *p_usart_opt, uint32_t ul_mck);
#if (SAM3S || SAM4S || SAM3U || SAM4L || SAM4E)
uint32_t usart_init_modem(Usart *p_usart,
const sam_usart_opt_t *p_usart_opt, uint32_t ul_mck);
#endif
uint32_t usart_init_sync_master(Usart *p_usart,
const sam_usart_opt_t *p_usart_opt, uint32_t ul_mck);
uint32_t usart_init_sync_slave(Usart *p_usart,
const sam_usart_opt_t *p_usart_opt);
uint32_t usart_init_rs485(Usart *p_usart,
const sam_usart_opt_t *p_usart_opt, uint32_t ul_mck);
#if (!SAMG55 && !SAMV71 && !SAMV70 && !SAME70 && !SAMS70)
uint32_t usart_init_irda(Usart *p_usart,
const sam_usart_opt_t *p_usart_opt, uint32_t ul_mck);
#endif
#if (!SAMV71 && !SAMV70 && !SAME70 && !SAMS70)
uint32_t usart_init_iso7816(Usart *p_usart,
const usart_iso7816_opt_t *p_usart_opt, uint32_t ul_mck);
void usart_reset_iterations(Usart *p_usart);
void usart_reset_nack(Usart *p_usart);
uint32_t usart_is_rx_buf_end(Usart *p_usart);
uint32_t usart_is_tx_buf_end(Usart *p_usart);
uint32_t usart_is_rx_buf_full(Usart *p_usart);
uint32_t usart_is_tx_buf_empty(Usart *p_usart);
uint8_t usart_get_error_number(Usart *p_usart);
#endif
uint32_t usart_init_spi_master(Usart *p_usart,
const usart_spi_opt_t *p_usart_opt, uint32_t ul_mck);
uint32_t usart_init_spi_slave(Usart *p_usart,
const usart_spi_opt_t *p_usart_opt);
#if (SAM3XA || SAM4L || SAMG55 || SAMV71 || SAMV70 || SAME70 || SAMS70)
uint32_t usart_init_lin_master(Usart *p_usart, uint32_t ul_baudrate,
uint32_t ul_mck);
uint32_t usart_init_lin_slave(Usart *p_usart, uint32_t ul_baudrate,
uint32_t ul_mck);
void usart_lin_abort_tx(Usart *p_usart);
void usart_lin_send_wakeup_signal(Usart *p_usart);
void usart_lin_set_node_action(Usart *p_usart, uint8_t uc_action);
void usart_lin_disable_parity(Usart *p_usart);
void usart_lin_enable_parity(Usart *p_usart);
void usart_lin_disable_checksum(Usart *p_usart);
void usart_lin_enable_checksum(Usart *p_usart);
void usart_lin_set_checksum_type(Usart *p_usart, uint8_t uc_type);
void usart_lin_set_data_len_mode(Usart *p_usart, uint8_t uc_mode);
void usart_lin_disable_frame_slot(Usart *p_usart);
void usart_lin_enable_frame_slot(Usart *p_usart);
void usart_lin_set_wakeup_signal_type(Usart *p_usart, uint8_t uc_type);
void usart_lin_set_response_data_len(Usart *p_usart, uint8_t uc_len);
void usart_lin_disable_pdc_mode(Usart *p_usart);
void usart_lin_enable_pdc_mode(Usart *p_usart);
void usart_lin_set_tx_identifier(Usart *p_usart, uint8_t uc_id);
uint8_t usart_lin_read_identifier(Usart *p_usart);
uint8_t usart_lin_get_data_length(Usart *usart);
#endif
#if (SAMV71 || SAMV70 || SAME70 || SAMS70)
uint8_t usart_lin_identifier_send_complete(Usart *usart);
uint8_t usart_lin_identifier_reception_complete(Usart *usart);
uint8_t usart_lin_tx_complete(Usart *usart);
uint32_t usart_init_lon(Usart *p_usart, uint32_t ul_baudrate, uint32_t ul_mck);
void usart_lon_set_comm_type(Usart *p_usart, uint8_t uc_type);
void usart_lon_disable_coll_detection(Usart *p_usart);
void usart_lon_enable_coll_detection(Usart *p_usart);
void usart_lon_set_tcol(Usart *p_usart, uint8_t uc_type);
void usart_lon_set_cdtail(Usart *p_usart, uint8_t uc_type);
void usart_lon_set_dmam(Usart *p_usart, uint8_t uc_type);
void usart_lon_set_beta1_tx_len(Usart *p_usart, uint32_t ul_len);
void usart_lon_set_beta1_rx_len(Usart *p_usart, uint32_t ul_len);
void usart_lon_set_priority(Usart *p_usart, uint8_t uc_psnb, uint8_t uc_nps);
void usart_lon_set_tx_idt(Usart *p_usart, uint32_t ul_time);
void usart_lon_set_rx_idt(Usart *p_usart, uint32_t ul_time);
void usart_lon_set_pre_len(Usart *p_usart, uint32_t ul_len);
void usart_lon_set_data_len(Usart *p_usart, uint8_t uc_len);
void usart_lon_set_l2hdr(Usart *p_usart, uint8_t uc_bli, uint8_t uc_altp, uint8_t uc_pb);
uint32_t usart_lon_is_tx_end(Usart *p_usart);
uint32_t usart_lon_is_rx_end(Usart *p_usart);
#endif
void usart_enable_tx(Usart *p_usart);
void usart_disable_tx(Usart *p_usart);
void usart_reset_tx(Usart *p_usart);
void usart_set_tx_timeguard(Usart *p_usart, uint32_t timeguard);
void usart_enable_rx(Usart *p_usart);
void usart_disable_rx(Usart *p_usart);
void usart_reset_rx(Usart *p_usart);
void usart_set_rx_timeout(Usart *p_usart, uint32_t timeout);
void usart_enable_interrupt(Usart *p_usart, uint32_t ul_sources);
void usart_disable_interrupt(Usart *p_usart, uint32_t ul_sources);
uint32_t usart_get_interrupt_mask(Usart *p_usart);
uint32_t usart_get_status(Usart *p_usart);
void usart_reset_status(Usart *p_usart);
void usart_start_tx_break(Usart *p_usart);
void usart_stop_tx_break(Usart *p_usart);
void usart_start_rx_timeout(Usart *p_usart);
uint32_t usart_send_address(Usart *p_usart, uint32_t ul_addr);
void usart_restart_rx_timeout(Usart *p_usart);
#if (SAM3S || SAM4S || SAM3U || SAM4L || SAM4E)
void usart_drive_DTR_pin_low(Usart *p_usart);
void usart_drive_DTR_pin_high(Usart *p_usart);
#endif
void usart_drive_RTS_pin_low(Usart *p_usart);
void usart_drive_RTS_pin_high(Usart *p_usart);
void usart_spi_force_chip_select(Usart *p_usart);
void usart_spi_release_chip_select(Usart *p_usart);
uint32_t usart_is_tx_ready(Usart *p_usart);
uint32_t usart_is_tx_empty(Usart *p_usart);
uint32_t usart_is_rx_ready(Usart *p_usart);
uint32_t usart_write(Usart *p_usart, uint32_t c);
uint32_t usart_putchar(Usart *p_usart, uint32_t c);
void usart_write_line(Usart *p_usart, const char *string);
uint32_t usart_read(Usart *p_usart, uint32_t *c);
uint32_t usart_getchar(Usart *p_usart, uint32_t *c);
#if (SAM3XA || SAM3U)
uint32_t *usart_get_tx_access(Usart *p_usart);
uint32_t *usart_get_rx_access(Usart *p_usart);
#endif
#if (!SAM4L && !SAMV71 && !SAMV70 && !SAME70 && !SAMS70)
Pdc *usart_get_pdc_base(Usart *p_usart);
#endif
void usart_enable_writeprotect(Usart *p_usart);
void usart_disable_writeprotect(Usart *p_usart);
uint32_t usart_get_writeprotect_status(Usart *p_usart);
#if (SAM3S || SAM4S || SAM3U || SAM3XA || SAM4L || SAM4E || SAM4C || SAM4CP || SAM4CM || SAMV70 || SAMV71 || SAMS70 || SAME70)
void usart_man_set_tx_pre_len(Usart *p_usart, uint8_t uc_len);
void usart_man_set_tx_pre_pattern(Usart *p_usart, uint8_t uc_pattern);
void usart_man_set_tx_polarity(Usart *p_usart, uint8_t uc_polarity);
void usart_man_set_rx_pre_len(Usart *p_usart, uint8_t uc_len);
void usart_man_set_rx_pre_pattern(Usart *p_usart, uint8_t uc_pattern);
void usart_man_set_rx_polarity(Usart *p_usart, uint8_t uc_polarity);
void usart_man_enable_drift_compensation(Usart *p_usart);
void usart_man_disable_drift_compensation(Usart *p_usart);
#endif
#if SAM4L
uint32_t usart_get_version(Usart *p_usart);
#endif
#if SAMG55
void usart_set_sleepwalking(Usart *p_uart, uint8_t ul_low_value,
bool cmpmode, bool cmppar, uint8_t ul_high_value);
#endif
/// @cond 0
/**INDENT-OFF**/
#ifdef __cplusplus
}
#endif
/**INDENT-ON**/
/// @endcond
//! @}
/**
* \page sam_usart_quickstart Quick start guide for the SAM USART module
*
* This is the quick start guide for the \ref group_sam_drivers_usart
* "USART module", with step-by-step instructions on how to configure and
* use the driver in a selection of use cases.
*
* The use cases contain several code fragments. The code fragments in the
* steps for setup can be copied into a custom initialization function, while
* the steps for usage can be copied into, e.g., the main application function.
*
* \note Some SAM devices contain both USART and UART modules, with the latter
* being a subset in functionality of the former but physically separate
* peripherals. UART modules are compatible with the USART driver, but
* only for the functions and modes supported by the base UART driver.
*
* \section usart_use_cases USART use cases
* - \ref usart_basic_use_case
* - \subpage usart_use_case_1
* - \subpage usart_use_case_2
*
* \note The USART pins configuration are not included here. Please refer
* the related code in board_init() function.
*
* \section usart_basic_use_case Basic use case - transmit a character
* In this use case, the USART module is configured for:
* - Using USART0
* - Baudrate: 9600
* - Character length: 8 bit
* - Parity mode: Disabled
* - Stop bit: None
* - RS232 mode
*
* \section usart_basic_use_case_setup Setup steps
*
* \subsection usart_basic_use_case_setup_prereq Prerequisites
* -# \ref sysclk_group "System Clock Management (sysclock)"
* -# \ref ioport_group "Common IOPORT API (ioport)"
*
* \subsection usart_basic_use_case_setup_code Example code
* The following configuration must be added to the project (typically to a
* conf_usart.h file, but it can also be added to your main application file.)
* \code
#define USART_SERIAL USART0
#define USART_SERIAL_ID ID_USART0 //USART0 for sam4l
#define USART_SERIAL_BAUDRATE 9600
#define USART_SERIAL_CHAR_LENGTH US_MR_CHRL_8_BIT
#define USART_SERIAL_PARITY US_MR_PAR_NO
#define USART_SERIAL_STOP_BIT US_MR_NBSTOP_1_BIT
\endcode
*
* Add to application initialization:
* \code
sysclk_init();
board_init();
const sam_usart_opt_t usart_console_settings = {
USART_SERIAL_BAUDRATE,
USART_SERIAL_CHAR_LENGTH,
USART_SERIAL_PARITY,
USART_SERIAL_STOP_BIT,
US_MR_CHMODE_NORMAL
};
#if SAM4L
sysclk_enable_peripheral_clock(USART_SERIAL);
#else
sysclk_enable_peripheral_clock(USART_SERIAL_ID);
#endif
usart_init_rs232(USART_SERIAL, &usart_console_settings,
sysclk_get_main_hz());
usart_enable_tx(USART_SERIAL);
usart_enable_rx(USART_SERIAL);
\endcode
*
* \subsection usart_basic_use_case_setup_flow Workflow
* -# Initialize system clock:
* \code
sysclk_init();
\endcode
* -# Configure the USART Tx and Rx pins by call the board init function:
* \code
board_init();
\endcode
* \note Set the following define in conf_board.h file to enable COM port,it will be used in
* board_init() function to set up IOPorts for the USART pins.
* For SAM4L:
* \code
#define CONF_BOARD_COM_PORT
\endcode
* For other SAM devices:
* \code
#define CONF_BOARD_UART_CONSOLE
\endcode
* -# Create USART options struct:
* \code
const sam_usart_opt_t usart_console_settings = {
USART_SERIAL_BAUDRATE,
USART_SERIAL_CHAR_LENGTH,
USART_SERIAL_PARITY,
USART_SERIAL_STOP_BIT,
US_MR_CHMODE_NORMAL
};
\endcode
* -# Enable the clock to the USART module:
* \code
#if SAM4L
sysclk_enable_peripheral_clock(USART_SERIAL);
#else
sysclk_enable_peripheral_clock(USART_SERIAL_ID);
#endif
\endcode
* -# Initialize the USART module in RS232 mode:
* \code
usart_init_rs232(USART_SERIAL, &usart_console_settings,
sysclk_get_main_hz());
\endcode
* -# Enable the Rx and Tx modes of the USART module:
* \code
usart_enable_tx(USART_SERIAL);
usart_enable_rx(USART_SERIAL);
\endcode
*
* \section usart_basic_use_case_usage Usage steps
*
* \subsection usart_basic_use_case_usage_code Example code
* Add to application C-file:
* \code
usart_putchar(USART_SERIAL, 'a');
\endcode
*
* \subsection usart_basic_use_case_usage_flow Workflow
* -# Send an 'a' character via USART
* \code usart_putchar(USART_SERIAL, 'a'); \endcode
*/
/**
* \page usart_use_case_1 USART receive character and echo back
*
* In this use case, the USART module is configured for:
* - Using USART0
* - Baudrate: 9600
* - Character length: 8 bit
* - Parity mode: Disabled
* - Stop bit: None
* - RS232 mode
*
* The use case waits for a received character on the configured USART and
* echoes the character back to the same USART.
*
* \section usart_use_case_1_setup Setup steps
*
* \subsection usart_use_case_1_setup_prereq Prerequisites
* -# \ref sysclk_group "System Clock Management (sysclock)"
* -# \ref ioport_group "Common IOPORT API (ioport)"
*
* \subsection usart_use_case_1_setup_code Example code
* The following configuration must be added to the project (typically to a
* conf_usart.h file, but it can also be added to your main application file.):
* \code
#define USART_SERIAL USART0
#define USART_SERIAL_ID ID_USART0 //USART0 for sam4l
#define USART_SERIAL_BAUDRATE 9600
#define USART_SERIAL_CHAR_LENGTH US_MR_CHRL_8_BIT
#define USART_SERIAL_PARITY US_MR_PAR_NO
#define USART_SERIAL_STOP_BIT US_MR_NBSTOP_1_BIT
\endcode
*
* A variable for the received byte must be added:
* \code
uint32_t received_byte;
\endcode
*
* Add to application initialization:
* \code
sysclk_init();
board_init();
const sam_usart_opt_t usart_console_settings = {
USART_SERIAL_BAUDRATE,
USART_SERIAL_CHAR_LENGTH,
USART_SERIAL_PARITY,
USART_SERIAL_STOP_BIT,
US_MR_CHMODE_NORMAL
};
#if SAM4L
sysclk_enable_peripheral_clock(USART_SERIAL);
#else
sysclk_enable_peripheral_clock(USART_SERIAL_ID);
#endif
usart_init_rs232(USART_SERIAL, &usart_console_settings,
sysclk_get_main_hz());
usart_enable_tx(USART_SERIAL);
usart_enable_rx(USART_SERIAL);
\endcode
*
* \subsection usart_use_case_1_setup_flow Workflow
* -# Initialize system clock:
* \code
sysclk_init();
\endcode
* -# Configure the USART Tx and Rx pins by call the board init function:
* \code
board_init();
\endcode
* \note Set the following define in conf_board.h file to enable COM port,it will be used in
* board_init() function to set up IOPorts for the USART pins.
* For SAM4L:
* \code
#define CONF_BOARD_COM_PORT
\endcode
* For other SAM devices:
* \code
#define CONF_BOARD_UART_CONSOLE
\endcode
* -# Create USART options struct:
* \code
const sam_usart_opt_t usart_console_settings = {
USART_SERIAL_BAUDRATE,
USART_SERIAL_CHAR_LENGTH,
USART_SERIAL_PARITY,
USART_SERIAL_STOP_BIT,
US_MR_CHMODE_NORMAL
};
\endcode
* -# Enable the clock to the USART module:
* \code
#if SAM4L
sysclk_enable_peripheral_clock(USART_SERIAL);
#else
sysclk_enable_peripheral_clock(USART_SERIAL_ID);
#endif
\endcode
* -# Initialize the USART module in RS232 mode:
* \code
usart_init_rs232(USART_SERIAL, &usart_console_settings,
sysclk_get_main_hz());
\endcode
* -# Enable the Rx and Tx modes of the USART module:
* \code
usart_enable_tx(USART_SERIAL);
usart_enable_rx(USART_SERIAL);
\endcode
*
* \section usart_use_case_1_usage Usage steps
*
* \subsection usart_use_case_1_usage_code Example code
* Add to, e.g., main loop in application C-file:
* \code
received_byte = usart_getchar(USART_SERIAL);
usart_putchar(USART_SERIAL, received_byte);
\endcode
*
* \subsection usart_use_case_1_usage_flow Workflow
* -# Wait for reception of a character:
* \code usart_getchar(USART_SERIAL, &received_byte); \endcode
* -# Echo the character back:
* \code usart_putchar(USART_SERIAL, received_byte); \endcode
*/
/**
* \page usart_use_case_2 USART receive character and echo back via interrupts
*
* In this use case, the USART module is configured for:
* - Using USART0
* - Baudrate: 9600
* - Character length: 8 bit
* - Parity mode: Disabled
* - Stop bit: None
* - RS232 mode
*
* The use case waits for a received character on the configured USART and
* echoes the character back to the same USART. The character reception is
* performed via an interrupt handler, rather than the polling method used
* in \ref usart_use_case_1.
*
* \section usart_use_case_2_setup Setup steps
*
* \subsection usart_use_case_2_setup_prereq Prerequisites
* -# \ref sysclk_group "System Clock Management (sysclock)"
* -# \ref pio_group "Parallel Input/Output Controller (pio)"
* -# \ref pmc_group "Power Management Controller (pmc)"
*
* \subsection usart_use_case_2_setup_code Example code
* The following configuration must be added to the project (typically to a
* conf_usart.h file, but it can also be added to your main application file.):
* \code
#define USART_SERIAL USART0
#define USART_SERIAL_ID ID_USART0 //USART0 for sam4l
#define USART_SERIAL_ISR_HANDLER USART0_Handler
#define USART_SERIAL_BAUDRATE 9600
#define USART_SERIAL_CHAR_LENGTH US_MR_CHRL_8_BIT
#define USART_SERIAL_PARITY US_MR_PAR_NO
#define USART_SERIAL_STOP_BIT US_MR_NBSTOP_1_BIT
\endcode
*
* A variable for the received byte must be added:
* \code
uint32_t received_byte;
\endcode
*
* Add to application initialization:
* \code
sysclk_init();
board_init();
const sam_usart_opt_t usart_console_settings = {
USART_SERIAL_BAUDRATE,
USART_SERIAL_CHAR_LENGTH,
USART_SERIAL_PARITY,
USART_SERIAL_STOP_BIT,
US_MR_CHMODE_NORMAL
};
#if SAM4L
sysclk_enable_peripheral_clock(USART_SERIAL);
#else
sysclk_enable_peripheral_clock(USART_SERIAL_ID);
#endif
usart_init_rs232(USART_SERIAL, &usart_console_settings,
sysclk_get_main_hz());
usart_enable_tx(USART_SERIAL);
usart_enable_rx(USART_SERIAL);
usart_enable_interrupt(USART_SERIAL, US_IER_RXRDY);
NVIC_EnableIRQ(USART_SERIAL_IRQ);
\endcode
*
* \subsection usart_use_case_2_setup_flow Workflow
* -# Initialize system clock:
* \code
sysclk_init();
\endcode
* -# Configure the USART Tx and Rx pins by call the board init function:
* \code
board_init();
\endcode
* \note Set the following define in conf_board.h file to enable COM port,it will be used in
* board_init() function to set up IOPorts for the USART pins.
* For SAM4L:
* \code
#define CONF_BOARD_COM_PORT
\endcode
* For other SAM devices:
* \code
#define CONF_BOARD_UART_CONSOLE
\endcode
* -# Create USART options struct:
* \code
const sam_usart_opt_t usart_console_settings = {
USART_SERIAL_BAUDRATE,
USART_SERIAL_CHAR_LENGTH,
USART_SERIAL_PARITY,
USART_SERIAL_STOP_BIT,
US_MR_CHMODE_NORMAL
};
\endcode
* -# Enable the clock to the USART module:
* \code
#if SAM4L
sysclk_enable_peripheral_clock(USART_SERIAL);
#else
sysclk_enable_peripheral_clock(USART_SERIAL_ID);
#endif
\endcode
* -# Initialize the USART module in RS232 mode:
* \code
usart_init_rs232(USART_SERIAL, &usart_console_settings,
sysclk_get_main_hz());
\endcode
* -# Enable the Rx and Tx modes of the USART module:
* \code
usart_enable_tx(USART_SERIAL);
usart_enable_rx(USART_SERIAL);
\endcode
* -# Enable the USART character reception interrupt, and general interrupts
* for the USART module.
* \code
usart_enable_interrupt(USART_SERIAL, US_IER_RXRDY);
NVIC_EnableIRQ(USART_SERIAL_IRQ);
\endcode
* \section usart_use_case_2_usage Usage steps
*
* \subsection usart_use_case_2_usage_code Example code
* Add to your main application C-file the USART interrupt handler:
* \code
void USART_SERIAL_ISR_HANDLER(void)
{
uint32_t dw_status = usart_get_status(USART_SERIAL);
if (dw_status & US_CSR_RXRDY) {
uint32_t received_byte;
usart_read(USART_SERIAL, &received_byte);
usart_write(USART_SERIAL, received_byte);
}
}
\endcode
*
* \subsection usart_use_case_2_usage_flow Workflow
* -# When the USART ISR fires, retrieve the USART module interrupt flags:
* \code uint32_t dw_status = usart_get_status(USART_SERIAL); \endcode
* -# Check if the USART Receive Character interrupt has fired:
* \code if (dw_status & US_CSR_RXRDY) \endcode
* -# If a character has been received, fetch it into a temporary variable:
* \code usart_read(USART_SERIAL, &received_byte); \endcode
* -# Echo the character back:
* \code usart_write(USART_SERIAL, received_byte); \endcode
*/
#endif /* USART_H_INCLUDED */