spi.h File Reference

Function prototypes for the SPI interface. More...

#include <stdint.h>
#include "stm32f4xx.h"
#include "defines.h"

Go to the source code of this file.

Data Structures
struct	SPIRegs
	Contains SPI/I2S registers. More...
struct	SPIISR
	Contains SPI interrupt configuration. More...
struct	SPIConfig
	Contains additional SPI configuration. More...

Macros
#define	SPI(ADDR)

Typedefs
typedef enum spi_peripheral	spi_peripheral_t
	Available SPI peripherals.
typedef enum spi_communication	spi_communication_t
	Available SPI communication modes.
typedef enum spi_nss_mode	spi_nss_mode_t
	Available SPI NSS pin modes.
typedef enum spi_prescaler	spi_prescaler_t
	Available SPI clock dividers.

Enumerations
enum	spi_peripheral { SPI_PERIPH_LEN }
	Available SPI peripherals.
enum	spi_communication {   SPI_COMM_FULLDUPLEX = 0x0 , SPI_COMM_HALFDUPLEX_RX , SPI_COMM_HALFDUPLEX_TX , SPI_COMM_SIMPLEX_RX ,   SPI_COMM_SIMPLEX_TX }
	Available SPI communication modes.
enum	spi_nss_mode { SPI_NSS_SOFT = 0x0 , SPI_NSS_HARD_OE , SPI_NSS_HARD_OD }
	Available SPI NSS pin modes.
enum	spi_prescaler {   SPI_PRESC_DIV2 = 0x0 , SPI_PRESC_DIV4 , SPI_PRESC_DIV8 , SPI_PRESC_DIV16 ,   SPI_PRESC_DIV32 , SPI_PRESC_DIV64 , SPI_PRESC_DIV128 , SPI_PRESC_DIV256 }
	Available SPI clock dividers.

Functions
void	spi_set_interrupts (const spi_peripheral_t spi, const struct SPIISR config)
	Enables specified SPI interrupts.
void	spi_configure_communication (const spi_peripheral_t spi, const spi_communication_t com, const spi_nss_mode_t nss)
	Configures the SPI communication / wiring.
void	spi_configure_clk (const spi_peripheral_t spi, const spi_prescaler_t div, _Bool polarity, _Bool phase)
	Configures the SPI prescale divider.
void	spi_set_ssi_state (const spi_peripheral_t spi, const _Bool state)
	Sets the internal SS to the desired state.
void	spi_set_dma (const spi_peripheral_t spi, const _Bool forTX, const _Bool forRX)
	Enables DMA for SPI RX and/or TX.
void	spi_configure_options (const spi_peripheral_t spi, const struct SPIConfig config)
	Set SPI options from specified config.
void	spi_tx_data (const spi_peripheral_t spi, const uint16_t data)
	Transmits specified SPI data.
uint16_t	spi_rx_data (const spi_peripheral_t spi)
	Reads the received SPI data.
uint16_t	spi_trx_data (const spi_peripheral_t spi, const uint16_t data)
	Transmit data, receive answer.
void	spi_start (const spi_peripheral_t spi, const _Bool master)
	Initiates the SPI peripheral with specified options.
void	spi_stop (const spi_peripheral_t spi)
	Stops the SPI peripheral communication.

Detailed Description

Function prototypes for the SPI interface.

This file contains all of the enums, macros, and function prototypes required for a functional SPI interface.

Multi-slave switching is not available, so please handle GPIOs manually.

Author

Vasileios Ch. (BillisC)

Bug

None, yet.

Macro Definition Documentation

SPI

#define SPI

(

ADDR

)

Value:

(struct SPIRegs *)(ADDR);

Function Documentation

spi_configure_clk()

void spi_configure_clk	(	const spi_peripheral_t	spi,
		const spi_prescaler_t	div,
		_Bool	polarity,
		_Bool	phase )

Configures the SPI prescale divider.

The available division values can be found in the spi_prescaler_t enum. Any other value will be ignored. Note that the prescaler will divide the clock speed of the bus of the peripheral and not the system clock. The resulting clock will be the baudrate of the SPI.

Parameters

spi	The selected SPI
div	The prescale divider
polarity	The default state of the clock
phase	Capture data on first or second pulse

Returns

None

spi_configure_communication()

void spi_configure_communication	(	const spi_peripheral_t	spi,
		const spi_communication_t	com,
		const spi_nss_mode_t	nss )

Configures the SPI communication / wiring.

The available communication and nss modes can be located under the spi_communication_t and spi_nss_mode_t enums. Any other value will be ignored.

Parameters

spi	The selected SPI
dir	The communication mode
nss	The NSS pin mode

Returns

None

spi_configure_options()

void spi_configure_options	(	const spi_peripheral_t	spi,
		const struct SPIConfig	config )

Set SPI options from specified config.

The SPI configuration is located under the SPIConfig struct. Refer to the datasheet for the correct usage of these options.

Parameters

spi	The selected SPI
config	The SPI configuration

Returns

None

spi_rx_data()

uint16_t spi_rx_data

(

const spi_peripheral_t

spi

)

Reads the received SPI data.

The data can be read as soon as they are stored in the RX buffer from the shift register. You may pair this with an interrupt for better performance.

Parameters

spi	The selected SPI

Returns

The received data

spi_set_dma()

void spi_set_dma	(	const spi_peripheral_t	spi,
		const _Bool	forTX,
		const _Bool	forRX )

Enables DMA for SPI RX and/or TX.

Parameters

spi	The selected SPI
forTX	Enable / disable DMA for TX
forRX	Enable / disable DMA for RX

Returns

None

spi_set_interrupts()

void spi_set_interrupts	(	const spi_peripheral_t	spi,
		const struct SPIISR	config )

Enables specified SPI interrupts.

The list of available SPI interrupts is located under the SPIISR struct.

Parameters

spi	The selected SPI
config	The interrupt config

Returns

None

spi_set_ssi_state()

void spi_set_ssi_state	(	const spi_peripheral_t	spi,
		const _Bool	state )

Sets the internal SS to the desired state.

Parameters

spi	The selected SPI
state	The SSI state

Returns

None

spi_start()

void spi_start	(	const spi_peripheral_t	spi,
		const _Bool	master )

Initiates the SPI peripheral with specified options.

Parameters

spi	The selected SPI
master	Use master configuration

Returns

None

spi_stop()

void spi_stop

(

const spi_peripheral_t

spi

)

Stops the SPI peripheral communication.

Parameters

spi	The selected SPI

Returns

None

spi_trx_data()

uint16_t spi_trx_data	(	const spi_peripheral_t	spi,
		const uint16_t	data )

Transmit data, receive answer.

A combination of TX and RX functions.

Parameters

spi	The selected SPI
data	The data to transmit

Returns

The received data

spi_tx_data()

void spi_tx_data	(	const spi_peripheral_t	spi,
		const uint16_t	data )

Transmits specified SPI data.

The data parameter is 16-bit but you may set the LSB for 8-bit transfers. The SPI loads the data in the shift register and transmits using the configured byte order.

Parameters

spi	The selected SPI
data	The data to transmit

Returns

None