usart_driver.h File Reference

XMEGA USART driver header file. More...

#include "avr_compiler.h"

Go to the source code of this file.

Macros
#define	USART_RX_BUFFER_SIZE   4
#define	USART_TX_BUFFER_SIZE   4
#define	USART_RX_BUFFER_MASK   ( USART_RX_BUFFER_SIZE - 1 )
#define	USART_TX_BUFFER_MASK   ( USART_TX_BUFFER_SIZE - 1 )
#define	USART_Format_Set(_usart, _charSize, _parityMode, _twoStopBits)
	Macro that sets the USART frame format.
#define	USART_Baudrate_Set(_usart, _bselValue, _bScaleFactor)
	Set USART baud rate.
#define	USART_Rx_Enable(_usart)   ((_usart)->CTRLB |= USART_RXEN_bm)
	Enable USART receiver.
#define	USART_Rx_Disable(_usart)   ((_usart)->CTRLB &= ~USART_RXEN_bm)
	Disable USART receiver.
#define	USART_Tx_Enable(_usart)   ((_usart)->CTRLB |= USART_TXEN_bm)
	Enable USART transmitter.
#define	USART_Tx_Disable(_usart)   ((_usart)->CTRLB &= ~USART_TXEN_bm)
	Disable USART transmitter.
#define	USART_RxdInterruptLevel_Set(_usart, _rxdIntLevel)   ((_usart)->CTRLA = ((_usart)->CTRLA & ~USART_RXCINTLVL_gm) | _rxdIntLevel)
	Set USART RXD interrupt level.
#define	USART_TxdInterruptLevel_Set(_usart, _txdIntLevel)   (_usart)->CTRLA = ((_usart)->CTRLA & ~USART_TXCINTLVL_gm) | _txdIntLevel
	Set USART TXD interrupt level.
#define	USART_DreInterruptLevel_Set(_usart, _dreIntLevel)   (_usart)->CTRLA = ((_usart)->CTRLA & ~USART_DREINTLVL_gm) | _dreIntLevel
	Set USART DRE interrupt level.
#define	USART_SetMode(_usart, _usartMode)   ((_usart)->CTRLC = ((_usart)->CTRLC & (~USART_CMODE_gm)) | _usartMode)
	Set the mode the USART run in.
#define	USART_IsTXDataRegisterEmpty(_usart)   (((_usart)->STATUS & USART_DREIF_bm) != 0)
	Check if data register empty flag is set.
#define	USART_PutChar(_usart, _data)   ((_usart)->DATA = _data)
	Put data (5-8 bit character).
#define	USART_IsRXComplete(_usart)   (((_usart)->STATUS & USART_RXCIF_bm) != 0)
	Checks if the RX complete interrupt flag is set.
#define	USART_GetChar(_usart)   ((_usart)->DATA)
	Get received data (5-8 bit character).

Detailed Description

XMEGA USART driver header file.

 This file contains the function prototypes and enumerator definitions
 for various configuration parameters for the XMEGA USART driver.

 The driver is not intended for size and/or speed critical code, since
 most functions are just a few lines of code, and the function call
 overhead would decrease code performance. The driver is intended for
 rapid prototyping and documentation purposes for getting started with
 the XMEGA ADC module.

 For size and/or speed critical code, it is recommended to copy the
 function contents directly into your application instead of making
 a function call.

Application note:

AVR1307: Using the XMEGA USART

Documentation

For comprehensive code documentation, supported compilers, compiler settings and supported devices see readme.html

Author

Atmel Corporation: http://www.atmel.com
Support email: avr@a.nosp@m.tmel.nosp@m..com

Revision:

1694

Date:

2008-07-29 14:21:58 +0200 (ti, 29 jul 2008)

Copyright (c) 2008, 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.

1. 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.

1. 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.

Macro Definition Documentation

#define USART_Baudrate_Set	(		_usart,
			_bselValue,
			_bScaleFactor
	)

Value:

(_usart)->BAUDCTRLA =(uint8_t)_bselValue;                                           \
   (_usart)->BAUDCTRLB =(_bScaleFactor << USART_BSCALE0_bp)|(_bselValue >> 8)

Set USART baud rate.

Sets the USART's baud rate register.

UBRR_Value : Value written to UBRR ScaleFactor : Time Base Generator Scale Factor

Equation for calculation of BSEL value in asynchronous normal speed mode: If ScaleFactor >= 0 BSEL = ((I/O clock frequency)/(2^(ScaleFactor)*16*Baudrate))-1 If ScaleFactor < 0 BSEL = (1/(2^(ScaleFactor)*16))*(((I/O clock frequency)/Baudrate)-1)

Note

See XMEGA manual for equations for calculation of BSEL value in other modes.

Parameters

_usart	Pointer to the USART module.
_bselValue	Value to write to BSEL part of Baud control register. Use uint16_t type.
_bScaleFactor	USART baud rate scale factor. Use uint8_t type

#define USART_DreInterruptLevel_Set	(		_usart,
			_dreIntLevel
	)		(_usart)->CTRLA = ((_usart)->CTRLA & ~USART_DREINTLVL_gm) | _dreIntLevel

Set USART DRE interrupt level.

Sets the interrupt level on Data Register interrupt.

Parameters

_usart	Pointer to the USART module.
_dreIntLevel	Interrupt level of the DRE interrupt. Use USART_DREINTLVL_t type.

#define USART_Format_Set	(		_usart,
			_charSize,
			_parityMode,
			_twoStopBits
	)

Value:

(_usart)->CTRLC = (uint8_t) _charSize | _parityMode |                      \
                     (_twoStopBits ? USART_SBMODE_bm : 0)

Macro that sets the USART frame format.

Sets the frame format, Frame Size, parity mode and number of stop bits.

Parameters

_usart	Pointer to the USART module
_charSize	The character size. Use USART_CHSIZE_t type.
_parityMode	The parity Mode. Use USART_PMODE_t type.
_twoStopBits	Enable two stop bit mode. Use bool type.

#define USART_GetChar

(

_usart

)

((_usart)->DATA)

Get received data (5-8 bit character).

This macro reads out the RX register. Use the macro USART_RX_Complete to check if anything is received.

Parameters

_usart

The USART module.

Return values

Received

data.

#define USART_IsRXComplete

(

_usart

)

(((_usart)->STATUS & USART_RXCIF_bm) != 0)

Checks if the RX complete interrupt flag is set.

Checks if the RX complete interrupt flag is set.

Parameters

_usart

The USART module.

#define USART_IsTXDataRegisterEmpty

(

_usart

)

(((_usart)->STATUS & USART_DREIF_bm) != 0)

Check if data register empty flag is set.

Parameters

_usart

The USART module.

#define USART_PutChar	(		_usart,
			_data
	)		((_usart)->DATA = _data)

Put data (5-8 bit character).

Use the macro USART_IsTXDataRegisterEmpty before using this function to put data to the TX register.

Parameters

_usart	The USART module.
_data	The data to send.

#define USART_Rx_Disable

(

_usart

)

((_usart)->CTRLB &= ~USART_RXEN_bm)

Disable USART receiver.

Parameters

_usart

Pointer to the USART module.

#define USART_Rx_Enable

(

_usart

)

((_usart)->CTRLB |= USART_RXEN_bm)

Enable USART receiver.

Parameters

_usart

Pointer to the USART module

#define USART_RxdInterruptLevel_Set	(		_usart,
			_rxdIntLevel
	)		((_usart)->CTRLA = ((_usart)->CTRLA & ~USART_RXCINTLVL_gm) | _rxdIntLevel)

Set USART RXD interrupt level.

Sets the interrupt level on RX Complete interrupt.

Parameters

_usart	Pointer to the USART module.
_rxdIntLevel	Interrupt level of the RXD interrupt. Use USART_RXCINTLVL_t type.

#define USART_SetMode	(		_usart,
			_usartMode
	)		((_usart)->CTRLC = ((_usart)->CTRLC & (~USART_CMODE_gm)) | _usartMode)

Set the mode the USART run in.

Set the mode the USART run in. The default mode is asynchronous mode.

Parameters

_usart	Pointer to the USART module register section.
_usartMode	Selects the USART mode. Use USART_CMODE_t type.

USART modes:

• 0x0 : Asynchronous mode.
• 0x1 : Synchronous mode.
• 0x2 : IrDA mode.
• 0x3 : Master SPI mode.

#define USART_Tx_Disable

(

_usart

)

((_usart)->CTRLB &= ~USART_TXEN_bm)

Disable USART transmitter.

Parameters

_usart

Pointer to the USART module.

#define USART_Tx_Enable

(

_usart

)

((_usart)->CTRLB |= USART_TXEN_bm)

Enable USART transmitter.

Parameters

_usart

Pointer to the USART module.

#define USART_TxdInterruptLevel_Set	(		_usart,
			_txdIntLevel
	)		(_usart)->CTRLA = ((_usart)->CTRLA & ~USART_TXCINTLVL_gm) | _txdIntLevel

Set USART TXD interrupt level.

Sets the interrupt level on TX Complete interrupt.

Parameters

_usart	Pointer to the USART module.
_txdIntLevel	Interrupt level of the TXD interrupt. Use USART_TXCINTLVL_t type.