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Diffstat (limited to 'lib/lufa/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h')
-rw-r--r-- | lib/lufa/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/lib/lufa/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h b/lib/lufa/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h new file mode 100644 index 0000000000..7244f4a954 --- /dev/null +++ b/lib/lufa/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h @@ -0,0 +1,258 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2017. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2017 Dean Camera (dean [at] fourwalledcubicle [dot] com) + + 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 + 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 + software without specific, written prior permission. + + The author disclaims all warranties with regard to this + software, including all implied warranties of merchantability + and fitness. In no event shall the author be liable for any + special, indirect or consequential damages or any damages + whatsoever resulting from loss of use, data or profits, whether + in an action of contract, negligence or other tortious action, + arising out of or in connection with the use or performance of + this software. +*/ + +/** \file + * \brief SPI Peripheral Driver (AVR8) + * + * On-chip SPI driver for the 8-bit AVR microcontrollers. + * + * \note This file should not be included directly. It is automatically included as needed by the SPI driver + * dispatch header located in LUFA/Drivers/Peripheral/SPI.h. + */ + +/** \ingroup Group_SPI + * \defgroup Group_SPI_AVR8 SPI Peripheral Driver (AVR8) + * + * \section Sec_SPI_AVR8_ModDescription Module Description + * Driver for the hardware SPI port available on most 8-bit AVR microcontroller models. This + * module provides an easy to use driver for the setup and transfer of data over the + * AVR's SPI port. + * + * \note This file should not be included directly. It is automatically included as needed by the SPI driver + * dispatch header located in LUFA/Drivers/Peripheral/SPI.h. + * + * \section Sec_SPI_AVR8_ExampleUsage Example Usage + * The following snippet is an example of how this module may be used within a typical + * application. + * + * \code + * // Initialize 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 + * + * @{ + */ + +#ifndef __SPI_AVR8_H__ +#define __SPI_AVR8_H__ + + /* Includes: */ + #include "../../../Common/Common.h" + + /* Enable C linkage for C++ Compilers: */ + #if defined(__cplusplus) + extern "C" { + #endif + + /* Preprocessor Checks: */ + #if !defined(__INCLUDE_FROM_SPI_H) + #error Do not include this file directly. Include LUFA/Drivers/Peripheral/SPI.h instead. + #endif + + /* Private Interface - For use in library only: */ + #if !defined(__DOXYGEN__) + /* Macros: */ + #define SPI_USE_DOUBLESPEED (1 << SPE) + #endif + + /* Public Interface - May be used in end-application: */ + /* Macros: */ + /** \name SPI Prescaler Configuration Masks */ + //@{ + /** SPI prescaler mask for \ref SPI_Init(). Divides the system clock by a factor of 2. */ + #define SPI_SPEED_FCPU_DIV_2 SPI_USE_DOUBLESPEED + + /** SPI prescaler mask for \ref SPI_Init(). Divides the system clock by a factor of 4. */ + #define SPI_SPEED_FCPU_DIV_4 0 + + /** SPI prescaler mask for \ref 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 \ref SPI_Init(). Divides the system clock by a factor of 16. */ + #define SPI_SPEED_FCPU_DIV_16 (1 << SPR0) + + /** SPI prescaler mask for \ref 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 \ref 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 \ref SPI_Init(). Divides the system clock by a factor of 128. */ + #define SPI_SPEED_FCPU_DIV_128 ((1 << SPR1) | (1 << SPR0)) + //@} + + /** \name SPI SCK Polarity Configuration Masks */ + //@{ + /** SPI clock polarity mask for \ref SPI_Init(). Indicates that the SCK should lead on the rising edge. */ + #define SPI_SCK_LEAD_RISING (0 << CPOL) + + /** SPI clock polarity mask for \ref SPI_Init(). Indicates that the SCK should lead on the falling edge. */ + #define SPI_SCK_LEAD_FALLING (1 << CPOL) + //@} + + /** \name SPI Sample Edge Configuration Masks */ + //@{ + /** SPI data sample mode mask for \ref SPI_Init(). Indicates that the data should sampled on the leading edge. */ + #define SPI_SAMPLE_LEADING (0 << CPHA) + + /** SPI data sample mode mask for \ref SPI_Init(). Indicates that the data should be sampled on the trailing edge. */ + #define SPI_SAMPLE_TRAILING (1 << CPHA) + //@} + + /** \name SPI Data Ordering Configuration Masks */ + //@{ + /** SPI data order mask for \ref SPI_Init(). Indicates that data should be shifted out MSB first. */ + #define SPI_ORDER_MSB_FIRST (0 << DORD) + + /** SPI data order mask for \ref SPI_Init(). Indicates that data should be shifted out LSB first. */ + #define SPI_ORDER_LSB_FIRST (1 << DORD) + //@} + + /** \name SPI Mode Configuration Masks */ + //@{ + /** SPI mode mask for \ref SPI_Init(). Indicates that the SPI interface should be initialized into slave mode. */ + #define SPI_MODE_SLAVE (0 << MSTR) + + /** SPI mode mask for \ref 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 + * SPI routines. + * + * \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); + static inline void SPI_Init(const uint8_t SPIOptions) + { + /* Prevent high rise times on PB.0 (/SS) from forcing a change to SPI slave mode */ + DDRB |= (1 << 0); + PORTB |= (1 << 0); + + DDRB |= ((1 << 1) | (1 << 2)); + DDRB &= ~(1 << 3); + PORTB |= (1 << 3); + + if (SPIOptions & SPI_USE_DOUBLESPEED) + SPSR |= (1 << SPI2X); + else + SPSR &= ~(1 << SPI2X); + + /* Switch /SS to input mode after configuration to allow for forced mode changes */ + DDRB &= ~(1 << 0); + + SPCR = ((1 << SPE) | SPIOptions); + } + + /** Turns off the SPI driver, disabling and returning used hardware to their default configuration. */ + static inline void SPI_Disable(void); + static inline void SPI_Disable(void) + { + DDRB &= ~((1 << 1) | (1 << 2)); + PORTB &= ~((1 << 0) | (1 << 3)); + + SPCR = 0; + SPSR = 0; + } + + /** Retrieves the currently selected SPI mode, once the SPI interface has been configured. + * + * \return \ref SPI_MODE_MASTER if the interface is currently in SPI Master mode, \ref SPI_MODE_SLAVE otherwise + */ + static inline uint8_t SPI_GetCurrentMode(void) ATTR_ALWAYS_INLINE; + static inline uint8_t SPI_GetCurrentMode(void) + { + return (SPCR & SPI_MODE_MASTER); + } + + /** 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. + * + * \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) + { + SPDR = Byte; + while (!(SPSR & (1 << SPIF))); + return SPDR; + } + + /** 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. + */ + static inline void SPI_SendByte(const uint8_t Byte) ATTR_ALWAYS_INLINE; + static inline void SPI_SendByte(const uint8_t Byte) + { + SPDR = Byte; + while (!(SPSR & (1 << SPIF))); + } + + /** 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. + */ + static inline uint8_t SPI_ReceiveByte(void) ATTR_ALWAYS_INLINE ATTR_WARN_UNUSED_RESULT; + static inline uint8_t SPI_ReceiveByte(void) + { + SPDR = 0x00; + while (!(SPSR & (1 << SPIF))); + return SPDR; + } + + /* Disable C linkage for C++ Compilers: */ + #if defined(__cplusplus) + } + #endif + +#endif + +/** @} */ + |