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/* ----------------------------------------------------------------------------
* ATMEL Microcontroller Software Support
* ----------------------------------------------------------------------------
* 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:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the disclaimer below.
*
* Atmel's name may not be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* DISCLAIMER: 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
* 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.
* ----------------------------------------------------------------------------
*/
//------------------------------------------------------------------------------
/// \dir
/// !Purpose
///
/// Definitions for SPI peripheral usage.
///
/// !Usage
///
/// -# Enable the SPI pins required by the application (see pio.h).
/// -# Configure the SPI using the SPI_Configure function. This enables the
/// peripheral clock. The mode register is loaded with the given value.
/// -# Configure all the necessary chip selects with SPI_ConfigureNPCS.
/// -# Enable the SPI by calling SPI_Enable.
/// -# Send/receive data using SPI_Write and SPI_Read. Note that SPI_Read
/// must be called after SPI_Write to retrieve the last value read.
/// -# Send/receive data using the PDC with the SPI_WriteBuffer and
/// SPI_ReadBuffer functions.
/// -# Disable the SPI by calling SPI_Disable.
//------------------------------------------------------------------------------
#ifndef SPI_H
#define SPI_H
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#include <board.h>
//------------------------------------------------------------------------------
// Definitions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
/// \page "SPI configuration macros"
/// This page lists several macros which should be used when configuring a SPI
/// peripheral.
///
/// !Macros
/// - SPI_PCS
/// - SPI_SCBR
/// - SPI_DLYBS
/// - SPI_DLYBCT
/// Calculate the PCS field value given the chip select NPCS value
#define SPI_PCS(npcs) ((~(1 << npcs) & 0xF) << 16)
/// Calculates the value of the CSR SCBR field given the baudrate and MCK.
#define SPI_SCBR(baudrate, masterClock) \
((unsigned int) (masterClock / baudrate) << 8)
/// Calculates the value of the CSR DLYBS field given the desired delay (in ns)
#define SPI_DLYBS(delay, masterClock) \
((unsigned int) (((masterClock / 1000000) * delay) / 1000) << 16)
/// Calculates the value of the CSR DLYBCT field given the desired delay (in ns)
#define SPI_DLYBCT(delay, masterClock) \
((unsigned int) (((masterClock / 1000000) * delay) / 32000) << 24)
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
// Exported functions
//------------------------------------------------------------------------------
extern void SPI_Enable(AT91S_SPI *spi);
extern void SPI_Disable(AT91S_SPI *spi);
extern void SPI_Configure(AT91S_SPI *spi,
unsigned int id,
unsigned int configuration);
extern void SPI_ConfigureNPCS(AT91S_SPI *spi,
unsigned int npcs,
unsigned int configuration);
extern void SPI_Write(AT91S_SPI *spi, unsigned int npcs, unsigned short data);
extern unsigned char SPI_WriteBuffer(AT91S_SPI *spi,
void *buffer,
unsigned int length);
extern unsigned char SPI_IsFinished(AT91S_SPI *pSpi);
extern unsigned short SPI_Read(AT91S_SPI *spi);
extern unsigned char SPI_ReadBuffer(AT91S_SPI *spi,
void *buffer,
unsigned int length);
#endif //#ifndef SPI_H
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