#include "../chip.h"
#include <stdint.h>

Macros
#define	USART_MODE_ASYNCHRONOUS (US_MR_CHRL_8_BIT \| US_MR_PAR_NO)

#define	USART_MODE_IRDA (AT91C_US_USMODE_IRDA \| AT91C_US_CHRL_8_BITS \| AT91C_US_PAR_NONE \| AT91C_US_FILTER)

#define	AT91C_US_USMODE_SPIM 0xE

#define	US_SPI_CPOL_0 (0x0<<16)

#define	US_SPI_CPHA_0 (0x0<<8)

#define	US_SPI_CPOL_1 (0x1<<16)

#define	US_SPI_CPHA_1 (0x1<<8)

#define	US_SPI_BPMODE_0 (US_SPI_CPOL_0\|US_SPI_CPHA_1)

#define	US_SPI_BPMODE_1 (US_SPI_CPOL_0\|US_SPI_CPHA_0)

#define	US_SPI_BPMODE_2 (US_SPI_CPOL_1\|US_SPI_CPHA_1)

#define	US_SPI_BPMODE_3 (US_SPI_CPOL_1\|US_SPI_CPHA_0)

Functions
void	USART_Configure (Usart *usart, uint32_t mode, uint32_t baudrate, uint32_t masterClock)
	Configures an USART peripheral with the specified parameters. More...

uint32_t	USART_GetStatus (Usart *usart)
	Get present status.

void	USART_EnableIt (Usart *usart, uint32_t mode)
	Enable interrupt.

void	USART_DisableIt (Usart *usart, uint32_t mode)
	Disable interrupt.

void	USART_SetTransmitterEnabled (Usart *usart, uint8_t enabled)
	Enables or disables the transmitter of an USART peripheral. More...

void	USART_SetReceiverEnabled (Usart *usart, uint8_t enabled)
	Enables or disables the receiver of an USART peripheral. More...

void	USART_Write (Usart *usart, uint16_t data, volatile uint32_t timeOut)
	Sends one packet of data through the specified USART peripheral. This function operates synchronously, so it only returns when the data has been actually sent. More...

uint8_t	USART_WriteBuffer (Usart usart, void buffer, uint32_t size)
	Sends the contents of a data buffer through the specified USART peripheral. This function returns immediately (1 if the buffer has been queued, 0 otherwise); poll the ENDTX and TXBUFE bits of the USART status register to check for the transfer completion. More...

uint16_t	USART_Read (Usart *usart, volatile uint32_t timeOut)
	Reads and return a packet of data on the specified USART peripheral. This function operates asynchronously, so it waits until some data has been received. More...

uint8_t	USART_ReadBuffer (Usart usart, void buffer, uint32_t size)
	Reads data from an USART peripheral, filling the provided buffer until it becomes full. This function returns immediately with 1 if the buffer has been queued for transmission; otherwise 0. More...

uint8_t	USART_IsDataAvailable (Usart *usart)
	Returns 1 if some data has been received and can be read from an USART; otherwise returns 0. More...

void	USART_SetIrdaFilter (Usart *pUsart, uint8_t filter)
	Sets the filter value for the IRDA demodulator. More...

void	USART_PutChar (Usart *usart, uint8_t c)
	Sends one packet of data through the specified USART peripheral. This function operates synchronously, so it only returns when the data has been actually sent. More...

uint32_t	USART_IsRxReady (Usart *usart)
	Return 1 if a character can be read in USART.

uint8_t	USART_GetChar (Usart *usart)
	Reads and returns a character from the USART. More...

Detailed Description

Purpose

This module provides several definitions and methods for using an USART peripheral.

Usage

Enable the USART peripheral clock in the PMC.
Enable the required USART PIOs (see pio.h).
Configure the UART by calling USART_Configure.
Enable the transmitter and/or the receiver of the USART using USART_SetTransmitterEnabled and USART_SetReceiverEnabled.
Send data through the USART using the USART_Write and USART_WriteBuffer methods.
Receive data from the USART using the USART_Read and USART_ReadBuffer functions; the availability of data can be polled with USART_IsDataAvailable.
Disable the transmitter and/or the receiver of the USART with USART_SetTransmitterEnabled and USART_SetReceiverEnabled.

Macro Definition Documentation

#define AT91C_US_USMODE_SPIM 0xE

SPI mode

#define USART_MODE_ASYNCHRONOUS (US_MR_CHRL_8_BIT | US_MR_PAR_NO)

USART modes

This section lists several common operating modes for an USART peripheral.

Modes

USART_MODE_ASYNCHRONOUS
USART_MODE_IRDABasic asynchronous mode, i.e. 8 bits no parity.

#define USART_MODE_IRDA (AT91C_US_USMODE_IRDA | AT91C_US_CHRL_8_BITS | AT91C_US_PAR_NONE | AT91C_US_FILTER)

IRDA mode

Function Documentation

void USART_Configure	(	Usart *	usart,
		uint32_t	mode,
		uint32_t	baudrate,
		uint32_t	masterClock
	)

Configures an USART peripheral with the specified parameters.

Parameters

usart	Pointer to the USART peripheral to configure.
mode	Desired value for the USART mode register (see the datasheet).
baudrate	Baudrate at which the USART should operate (in Hz).
masterClock	Frequency of the system master clock (in Hz).

uint8_t USART_GetChar ( Usart * usart )

Reads and returns a character from the USART.

Note: This function is synchronous (i.e. uses polling).

Parameters

usart Pointer to an USART peripheral.

Returns: Character received.

uint8_t USART_IsDataAvailable ( Usart * usart )

Returns 1 if some data has been received and can be read from an USART; otherwise returns 0.

Parameters

usart Pointer to an Usart instance.

void USART_PutChar	(	Usart *	usart,
		uint8_t	c
	)

Sends one packet of data through the specified USART peripheral. This function operates synchronously, so it only returns when the data has been actually sent.

Parameters

usart	Pointer to an USART peripheral.
c	Character to send

uint16_t USART_Read	(	Usart *	usart,
		volatile uint32_t	timeOut
	)

Reads and return a packet of data on the specified USART peripheral. This function operates asynchronously, so it waits until some data has been received.

Parameters

usart	Pointer to an USART peripheral.
timeOut	Time out value (0 -> no timeout).

uint8_t USART_ReadBuffer	(	Usart *	usart,
		void *	buffer,
		uint32_t	size
	)

Reads data from an USART peripheral, filling the provided buffer until it becomes full. This function returns immediately with 1 if the buffer has been queued for transmission; otherwise 0.

Parameters

usart	Pointer to an USART peripheral.
buffer	Pointer to the buffer where the received data will be stored.
size	Size of the data buffer (in bytes).

void USART_SetIrdaFilter	(	Usart *	pUsart,
		uint8_t	filter
	)

Sets the filter value for the IRDA demodulator.

Parameters

pUsart	Pointer to an Usart instance.
filter	Filter value.

void USART_SetReceiverEnabled	(	Usart *	usart,
		uint8_t	enabled
	)

Enables or disables the receiver of an USART peripheral.

Parameters

usart	Pointer to an USART peripheral
enabled	If true, the receiver is enabled; otherwise it is disabled.

void USART_SetTransmitterEnabled	(	Usart *	usart,
		uint8_t	enabled
	)

Enables or disables the transmitter of an USART peripheral.

Parameters

usart	Pointer to an USART peripheral
enabled	If true, the transmitter is enabled; otherwise it is disabled.

void USART_Write	(	Usart *	usart,
		uint16_t	data,
		volatile uint32_t	timeOut
	)

Sends one packet of data through the specified USART peripheral. This function operates synchronously, so it only returns when the data has been actually sent.

Parameters

usart	Pointer to an USART peripheral.
data	Data to send including 9nth bit and sync field if necessary (in the same format as the US_THR register in the datasheet).
timeOut	Time out value (0 = no timeout).

uint8_t USART_WriteBuffer	(	Usart *	usart,
		void *	buffer,
		uint32_t	size
	)

Sends the contents of a data buffer through the specified USART peripheral. This function returns immediately (1 if the buffer has been queued, 0 otherwise); poll the ENDTX and TXBUFE bits of the USART status register to check for the transfer completion.

Parameters

usart	Pointer to an USART peripheral.
buffer	Pointer to the data buffer to send.
size	Size of the data buffer (in bytes).

Macros

Functions

Detailed Description

Macro Definition Documentation

USART modes

Function Documentation