Serial Peripheral Interface (SPI) driver for SAM.

#include "compiler.h"

Macros
#define	spi_get_pcs(chip_sel_id) ((~(1u<<(chip_sel_id)))&0xF)
	Generate Peripheral Chip Select Value from Chip Select ID. More...

#define	SPI_TIMEOUT 15000
	Time-out value (number of attempts). More...

Typedefs
typedef enum spi_cs_behavior	spi_cs_behavior_t
	SPI Chip Select behavior modes while transferring. More...

Enumerations
enum	spi_cs_behavior { SPI_CS_KEEP_LOW = SPI_CSR_CSAAT, SPI_CS_RISE_NO_TX = 0, SPI_CS_RISE_FORCED = SPI_CSR_CSNAAT }
	SPI Chip Select behavior modes while transferring. More...

enum	spi_status_t { SPI_ERROR = -1, SPI_OK = 0, SPI_ERROR_TIMEOUT = 1, SPI_ERROR_ARGUMENT, SPI_ERROR_OVERRUN, SPI_ERROR_MODE_FAULT, SPI_ERROR_OVERRUN_AND_MODE_FAULT }
	Status codes used by the SPI driver. More...

Functions
int16_t	spi_calc_baudrate_div (const uint32_t baudrate, uint32_t mck)
	Calculate the baudrate divider. More...

void	spi_configure_cs_behavior (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_cs_behavior)
	Configure CS behavior for SPI transfer (spi_cs_behavior_t). More...

static void	spi_disable (Spi *p_spi)
	Disable SPI. More...

void	spi_disable_clock (Spi *p_spi)
	Disable SPI clock. More...

static void	spi_disable_interrupt (Spi *p_spi, uint32_t ul_sources)
	Disable SPI interrupts. More...

static void	spi_disable_loopback (Spi *p_spi)
	Disable loopback mode. More...

static void	spi_disable_mode_fault_detect (Spi *p_spi)
	Disable Mode Fault Detection. More...

static void	spi_disable_peripheral_select_decode (Spi *p_spi)
	Disable Peripheral Select Decode. More...

static void	spi_disable_tx_on_rx_empty (Spi *p_spi)
	Disable waiting RX_EMPTY before transfer starts. More...

static void	spi_enable (Spi *p_spi)
	Enable SPI. More...

void	spi_enable_clock (Spi *p_spi)
	Enable SPI clock. More...

static void	spi_enable_interrupt (Spi *p_spi, uint32_t ul_sources)
	Enable SPI interrupts. More...

static void	spi_enable_loopback (Spi *p_spi)
	Enable loopback mode. More...

static void	spi_enable_mode_fault_detect (Spi *p_spi)
	Enable Mode Fault Detection. More...

static void	spi_enable_peripheral_select_decode (Spi *p_spi)
	Enable Peripheral Select Decode. More...

static void	spi_enable_tx_on_rx_empty (Spi *p_spi)
	Enable waiting RX_EMPTY before transfer starts. More...

static uint16_t	spi_get (Spi *p_spi)
	Get one data to a SPI peripheral. More...

static uint32_t	spi_get_mode (Spi *p_spi)
	Get SPI work mode. More...

static uint32_t	spi_get_mode_fault_detect_setting (Spi *p_spi)
	Check if mode fault detection is enabled. More...

static Pdc *	spi_get_pdc_base (Spi *p_spi)
	Get PDC registers base address. More...

static uint32_t	spi_get_peripheral_select_decode_setting (Spi *p_spi)
	Get Peripheral Select Decode mode. More...

static uint32_t	spi_get_peripheral_select_mode (Spi *p_spi)
	Get Peripheral Select mode. More...

static void *	spi_get_rx_access (Spi *p_spi)
	Get receive data register address for DMA operation. More...

static void *	spi_get_tx_access (Spi *p_spi)
	Get transmit data register address for DMA operation. More...

static uint32_t	spi_get_tx_on_rx_empty_setting (Spi *p_spi)
	Check if SPI waits RX_EMPTY before transfer starts. More...

uint32_t	spi_get_writeprotect_status (Spi *p_spi)
	Indicate write protect status. More...

static uint32_t	spi_is_enabled (Spi *p_spi)
	Test if the SPI is enabled. More...

static uint32_t	spi_is_rx_full (Spi *p_spi)
	Check if the SPI contains a received character. More...

static uint32_t	spi_is_rx_ready (Spi *p_spi)
	Check if all receptions are ready. More...

static uint32_t	spi_is_tx_empty (Spi *p_spi)
	Check if all transmissions are complete. More...

static uint32_t	spi_is_tx_ready (Spi *p_spi)
	Check if all transmissions are ready. More...

static void	spi_put (Spi *p_spi, uint16_t data)
	Put one data to a SPI peripheral. More...

spi_status_t	spi_read (Spi p_spi, uint16_t us_data, uint8_t *p_pcs)
	Read the received data and it's peripheral chip select value. More...

static uint32_t	spi_read_interrupt_mask (Spi *p_spi)
	Read SPI interrupt mask. More...

static uint32_t	spi_read_status (Spi *p_spi)
	Read status register. More...

static void	spi_reset (Spi *p_spi)
	Reset SPI and set it to Slave mode. More...

int16_t	spi_set_baudrate_div (Spi *p_spi, uint32_t ul_pcs_ch, uint8_t uc_baudrate_divider)
	Set Serial Clock Baud Rate divider value (SCBR). More...

void	spi_set_bits_per_transfer (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_bits)
	Set number of bits per transfer. More...

void	spi_set_clock_phase (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_phase)
	Set Data Capture Phase. More...

void	spi_set_clock_polarity (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_polarity)
	Set clock default state. More...

void	spi_set_delay_between_chip_select (Spi *p_spi, uint32_t ul_delay)
	Set delay between chip selects (in number of MCK clocks). More...

static void	spi_set_fixed_peripheral_select (Spi *p_spi)
	Set Fixed Peripheral Select. More...

static void	spi_set_lastxfer (Spi *p_spi)
	Issue a LASTXFER command. More...

static void	spi_set_master_mode (Spi *p_spi)
	Set SPI to Master mode. More...

void	spi_set_peripheral_chip_select_value (Spi *p_spi, uint32_t ul_value)
	Set Peripheral Chip Select (PCS) value. More...

static void	spi_set_slave_mode (Spi *p_spi)
	Set SPI to Slave mode. More...

void	spi_set_transfer_delay (Spi *p_spi, uint32_t ul_pcs_ch, uint8_t uc_dlybs, uint8_t uc_dlybct)
	Configure timing for SPI transfer. More...

static void	spi_set_variable_peripheral_select (Spi *p_spi)
	Set Variable Peripheral Select. More...

void	spi_set_writeprotect (Spi *p_spi, uint32_t ul_enable)
	Enable or disable write protection of SPI registers. More...

spi_status_t	spi_write (Spi *p_spi, uint16_t us_data, uint8_t uc_pcs, uint8_t uc_last)
	Write the transmitted data with specified peripheral chip select value. More...

#define spi_get_pcs ( chip_sel_id ) ((~(1u<<(chip_sel_id)))&0xF)

Generate Peripheral Chip Select Value from Chip Select ID.

Note: When chip select n is working, PCS bit n is set to low level.

Parameters

chip_sel_id The chip select number used

#define SPI_TIMEOUT 15000

Time-out value (number of attempts).

Referenced by spi_read(), spi_read_packet(), spi_transceive_packet(), spi_write(), and spi_write_packet().

typedef enum spi_cs_behavior spi_cs_behavior_t

SPI Chip Select behavior modes while transferring.

enum spi_cs_behavior

SPI Chip Select behavior modes while transferring.

Enumerator
SPI_CS_KEEP_LOW	CS does not rise until a new transfer is requested on different chip select.
SPI_CS_RISE_NO_TX	CS rises if there is no more data to transfer.
SPI_CS_RISE_FORCED	CS is de-asserted systematically during a time DLYBCS.

enum spi_status_t

Status codes used by the SPI driver.

Enumerator
SPI_ERROR
SPI_OK
SPI_ERROR_TIMEOUT
SPI_ERROR_ARGUMENT
SPI_ERROR_OVERRUN
SPI_ERROR_MODE_FAULT
SPI_ERROR_OVERRUN_AND_MODE_FAULT

static void spi_disable ( Spi * p_spi )

inlinestatic

Disable SPI.

Note: CS is de-asserted, which indicates that the last data is done, and user should check TX_EMPTY before disabling SPI.

Parameters

p_spi Pointer to an SPI instance.

static void spi_disable_interrupt	(	Spi *	p_spi,
		uint32_t	ul_sources
	)

inlinestatic

Disable SPI interrupts.

Parameters

p_spi	Pointer to an SPI instance.
ul_sources	Interrupts to be disabled.

static void spi_disable_loopback ( Spi * p_spi )

inlinestatic

Disable loopback mode.

Parameters

p_spi Pointer to an SPI instance.

Referenced by spi_master_init().

static void spi_disable_mode_fault_detect ( Spi * p_spi )

inlinestatic

Disable Mode Fault Detection.

Parameters

p_spi Pointer to an SPI instance.

Referenced by spi_master_init().

static void spi_disable_peripheral_select_decode ( Spi * p_spi )

inlinestatic

Disable Peripheral Select Decode.

Parameters

p_spi Pointer to an SPI instance.

Referenced by spi_master_init().

static void spi_disable_tx_on_rx_empty ( Spi * p_spi )

inlinestatic

Disable waiting RX_EMPTY before transfer starts.

Parameters

p_spi Pointer to an SPI instance.

static void spi_enable ( Spi * p_spi )

inlinestatic

Enable SPI.

Parameters

p_spi Pointer to an SPI instance.

Referenced by ssd1306_interface_init().

static void spi_enable_interrupt	(	Spi *	p_spi,
		uint32_t	ul_sources
	)

inlinestatic

Enable SPI interrupts.

Parameters

p_spi	Pointer to an SPI instance.
ul_sources	Interrupts to be enabled.

static void spi_enable_loopback ( Spi * p_spi )

inlinestatic

Enable loopback mode.

Parameters

p_spi Pointer to an SPI instance.

static void spi_enable_mode_fault_detect ( Spi * p_spi )

inlinestatic

Enable Mode Fault Detection.

Parameters

p_spi Pointer to an SPI instance.

static void spi_enable_peripheral_select_decode ( Spi * p_spi )

inlinestatic

Enable Peripheral Select Decode.

Parameters

p_spi Pointer to an SPI instance.

static void spi_enable_tx_on_rx_empty ( Spi * p_spi )

inlinestatic

Enable waiting RX_EMPTY before transfer starts.

Parameters

p_spi Pointer to an SPI instance.

static uint16_t spi_get ( Spi * p_spi )

inlinestatic

Get one data to a SPI peripheral.

Parameters

p_spi Base address of the SPI instance.

Returns: The data byte

Referenced by spi_read_single().

static uint32_t spi_get_mode ( Spi * p_spi )

inlinestatic

Get SPI work mode.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 for master mode, 0 for slave mode.

static uint32_t spi_get_mode_fault_detect_setting ( Spi * p_spi )

inlinestatic

Check if mode fault detection is enabled.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 for disabled, 0 for enabled.

static Pdc* spi_get_pdc_base ( Spi * p_spi )

inlinestatic

Get PDC registers base address.

Parameters

p_spi Pointer to an SPI instance.

Returns: PDC registers base for PDC driver to access.

static uint32_t spi_get_peripheral_select_decode_setting ( Spi * p_spi )

inlinestatic

Get Peripheral Select Decode mode.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 for decode mode, 0 for direct mode.

Referenced by spi_select_device().

static uint32_t spi_get_peripheral_select_mode ( Spi * p_spi )

inlinestatic

Get Peripheral Select mode.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 for Variable mode, 0 for fixed mode.

Referenced by spi_read(), and spi_write().

static void* spi_get_rx_access ( Spi * p_spi )

inlinestatic

Get receive data register address for DMA operation.

Parameters

p_spi Pointer to an SPI instance.

Returns: Receive address for DMA access.

static void* spi_get_tx_access ( Spi * p_spi )

inlinestatic

Get transmit data register address for DMA operation.

Parameters

p_spi Pointer to an SPI instance.

Returns: Transmit address for DMA access.

static uint32_t spi_get_tx_on_rx_empty_setting ( Spi * p_spi )

inlinestatic

Check if SPI waits RX_EMPTY before transfer starts.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 for SPI waits, 0 for no wait.

static uint32_t spi_is_enabled ( Spi * p_spi )

inlinestatic

Test if the SPI is enabled.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 if the SPI is enabled, otherwise 0.

static uint32_t spi_is_rx_full ( Spi * p_spi )

inlinestatic

Check if the SPI contains a received character.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 if the SPI Receive Holding Register is full, otherwise 0.

static uint32_t spi_is_rx_ready ( Spi * p_spi )

inlinestatic

Check if all receptions are ready.

Parameters

p_spi Pointer to an SPI instance.

Returns: 1 if the SPI Receiver is ready, otherwise 0.

Referenced by spi_read_packet(), and spi_transceive_packet().

static uint32_t spi_is_tx_empty ( Spi * p_spi )

inlinestatic

Check if all transmissions are complete.

Parameters

p_spi Pointer to an SPI instance.

Return values

1	if transmissions are complete.
0	if transmissions are not complete.

Referenced by spi_deselect_device().

static uint32_t spi_is_tx_ready ( Spi * p_spi )

inlinestatic

Check if all transmissions are ready.

Parameters

p_spi Pointer to an SPI instance.

Return values

1	if transmissions are complete.
0	if transmissions are not complete.

Referenced by spi_read_packet(), spi_transceive_packet(), and spi_write_packet().

static void spi_put	(	Spi *	p_spi,
		uint16_t	data
	)

inlinestatic

Put one data to a SPI peripheral.

Parameters

p_spi	Base address of the SPI instance.
data	The data byte to be loaded

Referenced by spi_write_single().

static uint32_t spi_read_interrupt_mask ( Spi * p_spi )

inlinestatic

Read SPI interrupt mask.

Parameters

p_spi Pointer to an SPI instance.

Returns: The interrupt mask value.

static uint32_t spi_read_status ( Spi * p_spi )

inlinestatic

Read status register.

Parameters

p_spi Pointer to an SPI instance.

Returns: SPI status register value.

static void spi_reset ( Spi * p_spi )

inlinestatic

Reset SPI and set it to Slave mode.

Parameters

p_spi Pointer to an SPI instance.

Referenced by spi_master_init().

static void spi_set_fixed_peripheral_select ( Spi * p_spi )

inlinestatic

Set Fixed Peripheral Select.

Peripheral Chip Select is controlled by SPI_MR.

Parameters

p_spi Pointer to an SPI instance.

Referenced by spi_master_init().

static void spi_set_lastxfer ( Spi * p_spi )

inlinestatic

Issue a LASTXFER command.

The next transfer is the last transfer and after that CS is de-asserted.

Parameters

p_spi Pointer to an SPI instance.

Referenced by spi_deselect_device().

static void spi_set_master_mode ( Spi * p_spi )

inlinestatic

Set SPI to Master mode.

Parameters

p_spi Pointer to an SPI instance.

Referenced by spi_master_init().

static void spi_set_slave_mode ( Spi * p_spi )

inlinestatic

Set SPI to Slave mode.

Parameters

p_spi Pointer to an SPI instance.

static void spi_set_variable_peripheral_select ( Spi * p_spi )

inlinestatic

Set Variable Peripheral Select.

Peripheral Chip Select can be controlled by SPI_TDR.

Parameters

p_spi Pointer to an SPI instance.

Microchip® Advanced Software Framework

Macros

Typedefs

Enumerations

Functions