SPI Peripheral

The SPI peripheral is used for synchronous serial communication with other devices. More...

Enumerations
enum	spi_dopo_t { SPI_DOPO_0_SCK_1 = 0 , SPI_DOPO_2_SCK_3 , SPI_DOPO_3_SCK_1 , SPI_DOPO_0_SCK_3 }
enum	spi_dipo_t {   SPI_DIPO_0 = 0 , SPI_DIPO_1 , SPI_DIPO_2 , SPI_DIPO_3 ,   SPI_DIPO_NONE = 0xff }

Functions
void	spi_init (uint32_t baud)
	Initializes the SPI SERCOM as a controller for a board with a defined SPI_SERCOM.
void	spi_enable (void)
	Enables the SPI SERCOM for a board with a defined SPI_SERCOM.
bool	spi_is_enabled (void)
	Checks if the SPI peripheral is currently enabled for a board with a defined SPI_SERCOM.
uint8_t	spi_transfer (uint8_t data)
	Transfers a byte over SPI for a board with a defined SPI_SERCOM.
void	spi_disable (void)
	Disables the SPI SERCOM for a board with a defined SPI_SERCOM.
void	spi_init_instance (uint8_t sercom, spi_dopo_t dopo, spi_dipo_t dipo, uint32_t baud)
	Initializes a specific SERCOM instance as an SPI controller.
void	spi_enable_instance (uint8_t sercom)
	Enables a specific SERCOM instance for SPI.
bool	spi_is_enabled_instance (uint8_t sercom)
	Checks if the SPI peripheral on the given SERCOM is currently enabled.
uint8_t	spi_transfer_instance (uint8_t sercom, uint8_t data)
	Transfers a byte over SPI.
void	spi_disable_instance (uint8_t sercom)
	Disables a specific SERCOM instance for SPI.

Detailed Description

The SPI peripheral is used for synchronous serial communication with other devices.

Gossamer's SPI implementation only supports SPI controller mode, not peripheral mode. Your DOPO pin in this case is COPI/MOSI, and your DIPO pin is CIPO/MISO.

Function Documentation

spi_disable_instance()

void spi_disable_instance

(

uint8_t

sercom

)

Disables a specific SERCOM instance for SPI.

Parameters

sercom

The SERCOM instance to disable.

spi_enable_instance()

void spi_enable_instance

(

uint8_t

sercom

)

Enables a specific SERCOM instance for SPI.

Parameters

sercom

The SERCOM instance to enable.

spi_init()

void spi_init

(

uint32_t

baud

)

Initializes the SPI SERCOM as a controller for a board with a defined SPI_SERCOM.

Parameters

baud	The desired baud rate

spi_init_instance()

void spi_init_instance	(	uint8_t	sercom,
		spi_dopo_t	dopo,
		spi_dipo_t	dipo,
		uint32_t	baud )

Initializes a specific SERCOM instance as an SPI controller.

Parameters

sercom	The SERCOM instance to initialize.
dopo	The data out pinout.

See also

spi_dopo_t

Parameters

dipo	The data in pinout.

See also

spi_dipo_t

Parameters

baud	The desired baud rate

spi_is_enabled()

bool spi_is_enabled

(

void

)

Checks if the SPI peripheral is currently enabled for a board with a defined SPI_SERCOM.

Returns

true if SPI is enabled, false if it is not.

spi_is_enabled_instance()

bool spi_is_enabled_instance

(

uint8_t

sercom

)

Checks if the SPI peripheral on the given SERCOM is currently enabled.

Parameters

sercom

The SERCOM of the SPI peripheral, as numbered in the data sheet.

Returns

true if SPI is enabled, false if it is not.

spi_transfer()

uint8_t spi_transfer

(

uint8_t

data

)

Transfers a byte over SPI for a board with a defined SPI_SERCOM.

Parameters

data	The byte to send.

Returns

The byte received.

spi_transfer_instance()

uint8_t spi_transfer_instance	(	uint8_t	sercom,
		uint8_t	data )

Transfers a byte over SPI.

Parameters

sercom	The SERCOM instance to use.
data	The byte to send.

Returns

The byte received.

FIXME: Do we need to disable this check for a transmit-only SPI?