File syn_soft_spi.h¶

FileList > drivers > syn_soft_spi.h

Software SPI (bit-banging) driver. More...

#include "../common/syn_defs.h"
#include <stdbool.h>
#include <stdint.h>

Classes¶

Type	Name
struct	SYN_SoftSPI Software SPI instance.

Public Types¶

Type	Name
enum	SYN_SPIMode SPI Clock Mode.

Public Functions¶

Type	Name
void	syn_soft_spi_deselect (SYN_SoftSPI * spi) Deassert chip select (drive inactive).
void	syn_soft_spi_init (SYN_SoftSPI * spi, SYN_GPIO_Pin sck, SYN_GPIO_Pin mosi, SYN_GPIO_Pin miso, SYN_SPIMode mode, uint32_t delay_loops) Initialize the soft SPI pins.
void	syn_soft_spi_select (SYN_SoftSPI * spi) Assert chip select (drive active).
void	syn_soft_spi_set_cs (SYN_SoftSPI * spi, SYN_GPIO_Pin cs_pin, bool active_low) Set an optional chip select pin.
uint8_t	syn_soft_spi_transfer (const SYN_SoftSPI * spi, uint8_t data) Transfer a single byte (read and write simultaneously).
void	syn_soft_spi_transfer_bulk (SYN_SoftSPI * spi, const uint8_t * tx, uint8_t * rx, size_t len) Transfer multiple bytes.

Detailed Description¶

Implements SPI master functionality using any GPIO pins. Relies on syn_port_gpio.h for pin manipulation.

Public Types Documentation¶

enum SYN_SPIMode¶

SPI Clock Mode.

enum SYN_SPIMode {
    SYN_SPI_MODE_0 = 0,
    SYN_SPI_MODE_1 = 1,
    SYN_SPI_MODE_2 = 2,
    SYN_SPI_MODE_3 = 3
};

Public Functions Documentation¶

function syn_soft_spi_deselect¶

Deassert chip select (drive inactive).

void syn_soft_spi_deselect (
    SYN_SoftSPI * spi
)

Parameters:

spi Soft SPI instance.

function syn_soft_spi_init¶

Initialize the soft SPI pins.

void syn_soft_spi_init (
    SYN_SoftSPI * spi,
    SYN_GPIO_Pin sck,
    SYN_GPIO_Pin mosi,
    SYN_GPIO_Pin miso,
    SYN_SPIMode mode,
    uint32_t delay_loops
)

Parameters:

spi Pointer to SPI instance.
sck SCK pin.
mosi MOSI pin.
miso MISO pin.
mode SPI Mode (0-3).
delay_loops Number of iterations for a half-clock delay.

function syn_soft_spi_select¶

Assert chip select (drive active).

void syn_soft_spi_select (
    SYN_SoftSPI * spi
)

Parameters:

spi Soft SPI instance.

function syn_soft_spi_set_cs¶

Set an optional chip select pin.

void syn_soft_spi_set_cs (
    SYN_SoftSPI * spi,
    SYN_GPIO_Pin cs_pin,
    bool active_low
)

When set, syn_soft_spi_select/deselect can be used to assert/deassert CS.

Parameters:

spi SPI instance.
cs_pin Chip select GPIO pin.
active_low true if CS is active-low (most common).

function syn_soft_spi_transfer¶

Transfer a single byte (read and write simultaneously).

uint8_t syn_soft_spi_transfer (
    const SYN_SoftSPI * spi,
    uint8_t data
)

Parameters:

spi Pointer to SPI instance.
data Byte to write out on MOSI.

Returns:

Byte read in from MISO.

function syn_soft_spi_transfer_bulk¶

Transfer multiple bytes.

void syn_soft_spi_transfer_bulk (
    SYN_SoftSPI * spi,
    const uint8_t * tx,
    uint8_t * rx,
    size_t len
)

Parameters:

spi Pointer to SPI instance.
tx Buffer to transmit (can be NULL if rx-only).
rx Buffer to receive into (can be NULL if tx-only).
len Number of bytes to transfer.

The documentation for this class was generated from the following file src/syntropic/drivers/syn_soft_spi.h