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Diffstat (limited to 'LUFA/Drivers/AT90USBXXX/SPI.h')
-rw-r--r-- | LUFA/Drivers/AT90USBXXX/SPI.h | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/LUFA/Drivers/AT90USBXXX/SPI.h b/LUFA/Drivers/AT90USBXXX/SPI.h new file mode 100644 index 000000000..0b333a804 --- /dev/null +++ b/LUFA/Drivers/AT90USBXXX/SPI.h @@ -0,0 +1,139 @@ +/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2009.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.fourwalledcubicle.com
+*/
+
+/*
+ Copyright 2009 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+ Permission to use, copy, modify, and distribute this software
+ and its documentation for any purpose and without fee is hereby
+ granted, 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 disclaim 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
+ *
+ * Hardware SPI subsystem driver for the supported USB AVRs models.
+ */
+
+#ifndef __SPI_H__
+#define __SPI_H__
+
+ /* Includes: */
+ #include <stdbool.h>
+
+ /* Enable C linkage for C++ Compilers: */
+ #if defined(__cplusplus)
+ extern "C" {
+ #endif
+
+ /* Private Interface - For use in library only: */
+ #if !defined(__DOXYGEN__)
+ /* Macros: */
+ #define SPI_USE_DOUBLESPEED (1 << 7)
+ #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. */
+ #define SPI_SPEED_FCPU_DIV_2 SPI_USE_DOUBLESPEED
+
+ /** SPI prescaler mask for 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. */
+ #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. */
+ #define SPI_SPEED_FCPU_DIV_16 (1 << SPR0)
+
+ /** SPI prescaler mask for 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. */
+ #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. */
+ #define SPI_SPEED_FCPU_DIV_128 ((1 << SPR1) | (1 < SPR0))
+
+ /* Inline Functions: */
+ /** Initializes the SPI subsystem, ready for transfers. Must be called before calling any other
+ * SPI routines.
+ *
+ * \param PrescalerMask Prescaler mask to set the SPI clock speed
+ * \param Master If true, sets the SPI system to use master mode, slave if false
+ */
+ static inline void SPI_Init(const uint8_t PrescalerMask, const bool Master)
+ {
+ DDRB |= ((1 << 1) | (1 << 2));
+ PORTB |= ((1 << 0) | (1 << 3));
+
+ SPCR = ((1 << SPE) | (Master << MSTR) | (1 << CPOL) | (1 << CPHA) |
+ (PrescalerMask & ~SPI_USE_DOUBLESPEED));
+
+ if (PrescalerMask & SPI_USE_DOUBLESPEED)
+ SPSR = (1 << SPI2X);
+ }
+
+ /** Sends and receives a byte through the SPI interface, blocking until the transfer is complete.
+ *
+ * \param 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_ALWAYSINLINE;
+ 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 Byte Byte to send through the SPI interface
+ */
+ static inline void SPI_SendByte(const uint8_t Byte) ATTR_ALWAYSINLINE;
+ 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_ALWAYSINLINE 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
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