/*
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
* 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
+ *
* @{
*/
/* 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)
/** 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)
/** 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)
#if defined(__cplusplus)
}
#endif
-
+
#endif
/** @} */
+
projects / pub / USBasp.git / blobdiff