X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/071e02c6b6b4837fa9cf0b6d4c749994e02638d7..0019fbd1294ccc9ecb0ac4ddb5d8c71efcf9597f:/LUFA/Drivers/Peripheral/SPI.h diff --git a/LUFA/Drivers/Peripheral/SPI.h b/LUFA/Drivers/Peripheral/SPI.h index 9e6475351..0b8b17e1d 100644 --- a/LUFA/Drivers/Peripheral/SPI.h +++ b/LUFA/Drivers/Peripheral/SPI.h @@ -1,21 +1,21 @@ /* LUFA Library - Copyright (C) Dean Camera, 2010. - + Copyright (C) Dean Camera, 2011. + dean [at] fourwalledcubicle [dot] com - www.fourwalledcubicle.com + www.lufa-lib.org */ /* - Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com) + Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com) - Permission to use, copy, modify, distribute, and sell this + Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted - without fee, provided that the above copyright notice appear in + without fee, provided that the above copyright notice appear in all copies and that both that the copyright notice and this - permission notice and warranty disclaimer appear in supporting - documentation, and that the name of the author not be used in - advertising or publicity pertaining to distribution of the + permission notice and warranty disclaimer appear in supporting + documentation, and that the name of the author not be used in + advertising or publicity pertaining to distribution of the software without specific, written prior permission. The author disclaim all warranties with regard to this @@ -41,10 +41,33 @@ * The following files must be built with any user project that uses this module: * - None * - * \section Module Description + * \section Sec_ModDescription Module Description * Driver for the hardware SPI port available on most AVR models. This module provides * an easy to use driver for the setup of and transfer of data over the AVR's SPI port. * + * \section Sec_ExampleUsage Example Usage + * The following snippet is an example of how this module may be used within a typical + * application. + * + * \code + * // Initialise the SPI driver before first use + * SPI_Init(SPI_SPEED_FCPU_DIV_2 | SPI_ORDER_MSB_FIRST | SPI_SCK_LEAD_FALLING | + * SPI_SAMPLE_TRAILING | SPI_MODE_MASTER); + * + * // Send several bytes, ignoring the returned data + * SPI_SendByte(0x01); + * SPI_SendByte(0x02); + * SPI_SendByte(0x03); + * + * // Receive several bytes, sending a dummy 0x00 byte each time + * uint8_t Byte1 = SPI_ReceiveByte(); + * uint8_t Byte2 = SPI_ReceiveByte(); + * uint8_t Byte3 = SPI_ReceiveByte(); + * + * // Send a byte, and store the received byte from the same transaction + * uint8_t ResponseByte = SPI_TransferByte(0xDC); + * \endcode + * * @{ */ @@ -64,83 +87,105 @@ /* Macros: */ #define SPI_USE_DOUBLESPEED (1 << SPE) #endif - + /* Public Interface - May be used in end-application: */ /* Macros: */ - /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 2. */ + /** \name SPI Prescaler Configuration Masks */ + //@{ + /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 2. */ #define SPI_SPEED_FCPU_DIV_2 SPI_USE_DOUBLESPEED - /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 4. */ + /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 4. */ #define SPI_SPEED_FCPU_DIV_4 0 - /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 8. */ + /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 8. */ #define SPI_SPEED_FCPU_DIV_8 (SPI_USE_DOUBLESPEED | (1 << SPR0)) - /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 16. */ + /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 16. */ #define SPI_SPEED_FCPU_DIV_16 (1 << SPR0) - /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 32. */ + /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 32. */ #define SPI_SPEED_FCPU_DIV_32 (SPI_USE_DOUBLESPEED | (1 << SPR1)) - /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 64. */ + /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 64. */ #define SPI_SPEED_FCPU_DIV_64 (SPI_USE_DOUBLESPEED | (1 << SPR1) | (1 << SPR0)) - /** SPI prescaler mask for SPI_Init(). Divides the system clock by a factor of 128. */ + /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 128. */ #define SPI_SPEED_FCPU_DIV_128 ((1 << SPR1) | (1 << SPR0)) - - /** SPI clock polarity mask for SPI_Init(). Indicates that the SCK should lead on the rising edge. */ + //@} + + /** \name SPI SCK Polarity Configuration Masks */ + //@{ + /** SPI clock polarity mask for \c SPI_Init(). Indicates that the SCK should lead on the rising edge. */ #define SPI_SCK_LEAD_RISING (0 << CPOL) - /** SPI clock polarity mask for SPI_Init(). Indicates that the SCK should lead on the falling edge. */ + /** SPI clock polarity mask for \c SPI_Init(). Indicates that the SCK should lead on the falling edge. */ #define SPI_SCK_LEAD_FALLING (1 << CPOL) + //@} - /** SPI data sample mode mask for SPI_Init(). Indicates that the data should sampled on the leading edge. */ + /** \name SPI Sample Edge Configuration Masks */ + //@{ + /** SPI data sample mode mask for \c SPI_Init(). Indicates that the data should sampled on the leading edge. */ #define SPI_SAMPLE_LEADING (0 << CPHA) - /** SPI data sample mode mask for SPI_Init(). Indicates that the data should be sampled on the trailing edge. */ + /** SPI data sample mode mask for \c SPI_Init(). Indicates that the data should be sampled on the trailing edge. */ #define SPI_SAMPLE_TRAILING (1 << CPHA) + //@} - /** SPI mode mask for SPI_Init(). Indicates that the SPI interface should be initialized into slave mode. */ + /** \name SPI Data Ordering Configuration Masks */ + //@{ + /** SPI data order mask for \c SPI_Init(). Indicates that data should be shifted out MSB first. */ + #define SPI_ORDER_MSB_FIRST (0 << DORD) + + /** SPI data order mask for \c SPI_Init(). Indicates that data should be shifted out MSB first. */ + #define SPI_ORDER_LSB_FIRST (1 << DORD) + //@} + + /** \name SPI Mode Configuration Masks */ + //@{ + /** SPI mode mask for \c SPI_Init(). Indicates that the SPI interface should be initialized into slave mode. */ #define SPI_MODE_SLAVE (0 << MSTR) - /** SPI mode mask for SPI_Init(). Indicates that the SPI interface should be initialized into master mode. */ + /** SPI mode mask for \c SPI_Init(). Indicates that the SPI interface should be initialized into master mode. */ #define SPI_MODE_MASTER (1 << MSTR) - + //@} + /* Inline Functions: */ - /** Initializes the SPI subsystem, ready for transfers. Must be called before calling any other + /** Initialises the SPI subsystem, ready for transfers. Must be called before calling any other * SPI routines. * - * \param[in] SPIOptions SPI Options, a mask consisting of one of each of the SPI_SPEED_*, - * SPI_SCK_*, SPI_SAMPLE_* and SPI_MODE_* masks + * \param[in] SPIOptions SPI Options, a mask consisting of one of each of the \c SPI_SPEED_*, + * \c SPI_SCK_*, \c SPI_SAMPLE_*, \c SPI_ORDER_* and \c SPI_MODE_* masks. */ static inline void SPI_Init(const uint8_t SPIOptions) { - DDRB |= ((1 << 1) | (1 << 2)); - PORTB |= ((1 << 0) | (1 << 3)); - + DDRB |= ((1 << 1) | (1 << 2)); + DDRB &= ~((1 << 0) | (1 << 3)); + PORTB |= ((1 << 0) | (1 << 3)); + SPCR = ((1 << SPE) | SPIOptions); - + if (SPIOptions & SPI_USE_DOUBLESPEED) SPSR |= (1 << SPI2X); else SPSR &= ~(1 << SPI2X); } - + /** Turns off the SPI driver, disabling and returning used hardware to their default configuration. */ - static inline void SPI_ShutDown(void) + static inline void SPI_Disable(void) { DDRB &= ~((1 << 1) | (1 << 2)); PORTB &= ~((1 << 0) | (1 << 3)); - + SPCR = 0; SPSR = 0; } - + /** Sends and receives a byte through the SPI interface, blocking until the transfer is complete. * - * \param[in] Byte Byte to send through the SPI interface + * \param[in] Byte Byte to send through the SPI interface. * - * \return Response byte from the attached SPI device + * \return Response byte from the attached SPI device. */ static inline uint8_t SPI_TransferByte(const uint8_t Byte) ATTR_ALWAYS_INLINE; static inline uint8_t SPI_TransferByte(const uint8_t Byte) @@ -153,7 +198,7 @@ /** Sends a byte through the SPI interface, blocking until the transfer is complete. The response * byte sent to from the attached SPI device is ignored. * - * \param[in] Byte Byte to send through the SPI interface + * \param[in] Byte Byte to send through the SPI interface. */ static inline void SPI_SendByte(const uint8_t Byte) ATTR_ALWAYS_INLINE; static inline void SPI_SendByte(const uint8_t Byte) @@ -165,7 +210,7 @@ /** Sends a dummy byte through the SPI interface, blocking until the transfer is complete. The response * byte from the attached SPI device is returned. * - * \return The response byte from the attached SPI device + * \return The response byte from the attached SPI device. */ static inline uint8_t SPI_ReceiveByte(void) ATTR_ALWAYS_INLINE ATTR_WARN_UNUSED_RESULT; static inline uint8_t SPI_ReceiveByte(void) @@ -179,7 +224,8 @@ #if defined(__cplusplus) } #endif - + #endif /** @} */ +