X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/f01a05415c03b0dd61297849ece2cfcce7f8d3e8..615d34f1b7b363dc9c1cc79be6834e1e88c30ee8:/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h diff --git a/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h b/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h index 634c54480..3ca037606 100644 --- a/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h +++ b/LUFA/Drivers/Peripheral/AVR8/SPI_AVR8.h @@ -1,13 +1,13 @@ /* LUFA Library - Copyright (C) Dean Camera, 2011. + Copyright (C) Dean Camera, 2012. dean [at] fourwalledcubicle [dot] com www.lufa-lib.org */ /* - Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com) + Copyright 2012 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 @@ -56,21 +56,21 @@ * // 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 - * + * * @{ */ @@ -100,64 +100,64 @@ /* Macros: */ /** \name SPI Prescaler Configuration Masks */ //@{ - /** SPI prescaler mask for \c SPI_Init(). Divides the system clock by a factor of 2. */ + /** 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 \c SPI_Init(). Divides the system clock by a factor of 4. */ + /** 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 \c SPI_Init(). Divides the system clock by a factor of 8. */ + /** 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 \c SPI_Init(). Divides the system clock by a factor of 16. */ + /** 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 \c SPI_Init(). Divides the system clock by a factor of 32. */ + /** 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 \c SPI_Init(). Divides the system clock by a factor of 64. */ + /** 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 \c SPI_Init(). Divides the system clock by a factor of 128. */ + /** 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 \c SPI_Init(). Indicates that the SCK should lead on the rising edge. */ + /** 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 \c SPI_Init(). Indicates that the SCK should lead on the falling edge. */ + /** 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 \c SPI_Init(). Indicates that the data should sampled on the leading edge. */ + /** 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 \c SPI_Init(). Indicates that the data should be sampled on the trailing edge. */ + /** 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 \c SPI_Init(). Indicates that data should be shifted out MSB first. */ + /** 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 \c SPI_Init(). Indicates that data should be shifted out MSB first. */ + /** 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 \c SPI_Init(). Indicates that the SPI interface should be initialized into slave mode. */ + /** 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 \c SPI_Init(). Indicates that the SPI interface should be initialized into master mode. */ + /** 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. @@ -167,16 +167,23 @@ */ static inline void SPI_Init(const uint8_t SPIOptions) { - DDRB |= ((1 << 1) | (1 << 2)); - DDRB &= ~((1 << 0) | (1 << 3)); - PORTB |= ((1 << 0) | (1 << 3)); + /* Prevent high rise times on PB.0 (/SS) from forcing a change to SPI slave mode */ + DDRB |= (1 << 0); + PORTB |= (1 << 0); - SPCR = ((1 << SPE) | SPIOptions); + 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. */ @@ -189,6 +196,16 @@ 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.