The section describes the programming interface of the DSPI HAL driver. More...

Data Structures
struct	dspi_data_format_config_t
	DSPI data format settings configuration structure. More...

struct	dspi_master_config_t
	DSPI hardware configuration settings for master mode. More...

struct	dspi_slave_config_t
	DSPI hardware configuration settings for slave mode. More...

struct	dspi_baud_rate_divisors_t
	DSPI baud rate divisors settings configuration structure. More...

struct	dspi_delay_settings_config_t
	DSPI delay settings configuration structure. More...

struct	dspi_command_config_t
	DSPI command and data configuration structure. More...

Enumerations
enum	dspi_status_t { kStatus_DSPI_Success = 0, kStatus_DSPI_SlaveTxUnderrun, kStatus_DSPI_SlaveRxOverrun, kStatus_DSPI_Timeout, kStatus_DSPI_Busy, kStatus_DSPI_NoTransferInProgress, kStatus_DSPI_InvalidBitCount, kStatus_DSPI_InvalidInstanceNumber, kStatus_DSPI_OutOfRange }
	Error codes for the DSPI driver. More...

enum	dspi_master_slave_mode_t { kDspiMaster = 1, kDspiSlave = 0 }
	DSPI master or slave configuration. More...

enum	dspi_clock_polarity_t { kDspiClockPolarity_ActiveHigh = 0, kDspiClockPolarity_ActiveLow = 1 }
	DSPI clock polarity configuration for a given CTAR. More...

enum	dspi_clock_phase_t { kDspiClockPhase_FirstEdge = 0, kDspiClockPhase_SecondEdge = 1 }
	DSPI clock phase configuration for a given CTAR. More...

enum	dspi_shift_direction_t { kDspiMsbFirst = 0, kDspiLsbFirst = 1 }
	DSPI data shifter direction options for a given CTAR. More...

enum	dspi_ctar_selection_t { kDspiCtar0 = 0, kDspiCtar1 = 1 }
	DSPI Clock and Transfer Attributes Register (CTAR) selection. More...

enum	dspi_pcs_polarity_config_t { kDspiPcs_ActiveHigh = 0, kDspiPcs_ActiveLow = 1 }
	DSPI Peripheral Chip Select (PCS) Polarity configuration. More...

enum	dspi_which_pcs_config_t { kDspiPcs0 = 1 << 0, kDspiPcs1 = 1 << 1, kDspiPcs2 = 1 << 2, kDspiPcs3 = 1 << 3, kDspiPcs4 = 1 << 4, kDspiPcs5 = 1 << 5 }
	DSPI Peripheral Chip Select (PCS) configuration (which PCS to configure) More...

enum	dspi_master_sample_point_t { kDspiSckToSin_0Clock = 0, kDspiSckToSin_1Clock = 1, kDspiSckToSin_2Clock = 2 }
	DSPI Sample Point: Controls when the DSPI master samples SIN in Modified Transfer Format. More...

enum	dspi_fifo_t { kDspiTxFifo = 0, kDspiRxFifo = 1 }
	DSPI FIFO selects. More...

enum	dspi_status_and_interrupt_request_t { kDspiTxComplete = BP_SPI_RSER_TCF_RE, kDspiTxAndRxStatus = BP_SPI_SR_TXRXS, kDspiEndOfQueue = BP_SPI_RSER_EOQF_RE, kDspiTxFifoUnderflow = BP_SPI_RSER_TFUF_RE, kDspiTxFifoFillRequest = BP_SPI_RSER_TFFF_RE, kDspiRxFifoOverflow = BP_SPI_RSER_RFOF_RE, kDspiRxFifoDrainRequest = BP_SPI_RSER_RFDF_RE }
	DSPI status flags and interrupt request enable. More...

enum	dspi_fifo_counter_pointer_t { kDspiRxFifoPointer = BP_SPI_SR_POPNXTPTR, kDspiRxFifoCounter = BP_SPI_SR_RXCTR, kDspiTxFifoPointer = BP_SPI_SR_TXNXTPTR, kDspiTxFifoCounter = BP_SPI_SR_TXCTR }
	DSPI FIFO counter or pointer defines based on bit positions. More...

Variables
static const uint32_t	s_baudratePrescaler [] = { 2, 3, 5, 7 }

static const uint32_t	s_baudrateScaler []

uint32_t	dspi_data_format_config_t::bitsPerFrame
	Bits per frame, minimum 4, maximum 16 (master), 32 (slave)

dspi_clock_polarity_t	dspi_data_format_config_t::clkPolarity
	Active high or low clock polarity.

dspi_clock_phase_t	dspi_data_format_config_t::clkPhase
	Clock phase setting to change and capture data.

dspi_shift_direction_t	dspi_data_format_config_t::direction
	MSB or LSB data shift direction This setting relevant only in master mode and can be ignored in slave mode.

bool	dspi_master_config_t::isEnabled
	Set to true to enable the DSPI peripheral. More...

dspi_ctar_selection_t	dspi_master_config_t::whichCtar
	Desired Clock and Transfer Attributes Register (CTAR)

uint32_t	dspi_master_config_t::bitsPerSec
	Baud rate in bits per second.

uint32_t	dspi_master_config_t::sourceClockInHz
	Module source clock.

dspi_data_format_config_t	dspi_master_config_t::dataConfig
	Data format configuration structure.

bool	dspi_master_config_t::isSckContinuous
	Disable(0) or Enable(1) continuous SCK operation.

dspi_which_pcs_config_t	dspi_master_config_t::whichPcs
	Desired Peripheral Chip Select (PCS)

dspi_pcs_polarity_config_t	dspi_master_config_t::pcsPolarity
	Peripheral Chip Select (PCS) polarity setting. More...

dspi_master_sample_point_t	dspi_master_config_t::masterInSample
	Master data-in (SIN) sample point setting. More...

bool	dspi_master_config_t::isModifiedTimingFormatEnabled
	Disable(0) or Enable(1) modified timing format. More...

bool	dspi_master_config_t::isTxFifoDisabled
	Disable(1) or Enable(0) Tx FIFO.

bool	dspi_master_config_t::isRxFifoDisabled
	Disable(1) or Enable(0) Rx FIFO.

bool	dspi_slave_config_t::isEnabled
	Set to true to enable the DSPI peripheral. More...

dspi_data_format_config_t	dspi_slave_config_t::dataConfig
	Data format configuration structure.

bool	dspi_slave_config_t::isTxFifoDisabled
	Disable(1) or Enable(0) Tx FIFO.

bool	dspi_slave_config_t::isRxFifoDisabled
	Disable(1) or Enable(0) Rx FIFO.

bool	dspi_baud_rate_divisors_t::doubleBaudRate
	Double Baud rate parameter setting.

uint32_t	dspi_baud_rate_divisors_t::prescaleDivisor
	Baud Rate Pre-scalar parameter setting.

uint32_t	dspi_baud_rate_divisors_t::baudRateDivisor
	Baud Rate scaler parameter setting.

uint32_t	dspi_delay_settings_config_t::pcsToSckPre
	PCS to SCK delay pre-scalar (PCSSCK)

uint32_t	dspi_delay_settings_config_t::pcsToSck
	PCS to SCK Delay scalar (CSSCK)

uint32_t	dspi_delay_settings_config_t::afterSckPre
	After SCK delay pre-scalar (PASC)

uint32_t	dspi_delay_settings_config_t::afterSck
	After SCK delay scalar (ASC)

uint32_t	dspi_delay_settings_config_t::afterTransferPre
	Delay after transfer pre-scalar (PDT)

uint32_t	dspi_delay_settings_config_t::afterTransfer
	Delay after transfer scalar (DT)

bool	dspi_command_config_t::isChipSelectContinuous
	Option to enable the continuous assertion of chip select between transfers.

dspi_ctar_selection_t	dspi_command_config_t::whichCtar
	The desired Clock and Transfer Attributes Register (CTAR) to use for CTAS.

dspi_which_pcs_config_t	dspi_command_config_t::whichPcs
	The desired PCS signal to use for the data transfer.

bool	dspi_command_config_t::isEndOfQueue
	Signals that the current transfer is the last in the queue.

bool	dspi_command_config_t::clearTransferCount
	Clears SPI_TCNT field; cleared before transmission starts.

Configuration
dspi_status_t	dspi_hal_master_init (uint32_t instance, const dspi_master_config_t config, uint32_t calculatedBaudRate)
	Configure the DSPI peripheral in master mode. More...

dspi_status_t	dspi_hal_slave_init (uint32_t instance, const dspi_slave_config_t *config)
	Configures the DSPI peripheral in slave mode. More...

void	dspi_hal_reset (uint32_t instance)
	Restores the DSPI to reset the configuration. More...

static void	dspi_hal_enable (uint32_t instance)
	Enable the DSPI peripheral, set MCR MDIS to 0. More...

static void	dspi_hal_disable (uint32_t instance)
	Disables the DSPI peripheral, sets MCR MDIS to 1. More...

uint32_t	dspi_hal_set_baud (uint32_t instance, dspi_ctar_selection_t whichCtar, uint32_t bitsPerSec, uint32_t sourceClockInHz)
	Sets the DSPI baud rate in bits per second. More...

void	dspi_hal_set_baud_divisors (uint32_t instance, dspi_ctar_selection_t whichCtar, const dspi_baud_rate_divisors_t *divisors)
	Configures the baud rate divisors manually. More...

static void	dspi_hal_set_master_slave (uint32_t instance, dspi_master_slave_mode_t mode)
	Configures the DSPI for master or slave. More...

static void	dspi_hal_configure_continuous_sck (uint32_t instance, bool enable)
	Configures the DSPI for the continuous SCK operation. More...

static void	dspi_hal_configure_modified_timing_format (uint32_t instance, bool enable)
	Configures the DSPI to enable modified timing format. More...

static void	dspi_hal_configure_pcs_strobe (uint32_t instance, bool enable)
	Configures the DSPI peripheral chip select strobe enable. More...

static void	dspi_hal_configure_rx_fifo_overwrite (uint32_t instance, bool enable)
	Configures the DSPI received FIFO overflow overwrite enable. More...

void	dspi_hal_configure_pcs_polarity (uint32_t instance, dspi_which_pcs_config_t pcs, dspi_pcs_polarity_config_t activeLowOrHigh)
	Configures the DSPI peripheral chip select polarity. More...

void	dspi_hal_configure_fifos (uint32_t instance, bool disableTxFifo, bool disableRxFifo)
	Configures the DSPI FIFOs. More...

void	dspi_hal_flush_fifos (uint32_t instance, bool enableFlushTxFifo, bool enableFlushRxFifo)
	Flushes the DSPI FIFOs. More...

static void	dspi_hal_set_datain_samplepoint (uint32_t instance, dspi_master_sample_point_t samplePnt)
	Configures when the DSPI master samples SIN in the Modified Transfer Format. More...

static void	dspi_hal_start_transfer (uint32_t instance)
	Starts the DSPI transfers, clears HALT bit in MCR. More...

static void	dspi_hal_stop_transfer (uint32_t instance)
	Stops (halts) DSPI transfers, sets HALT bit in MCR. More...

dspi_status_t	dspi_hal_configure_data_format (uint32_t instance, dspi_ctar_selection_t whichCtar, const dspi_data_format_config_t *config)
	Configures the data format for a particular CTAR. More...

void	dspi_hal_configure_delays (uint32_t instance, dspi_ctar_selection_t whichCtar, const dspi_delay_settings_config_t *config)
	Configures the delays for a particular CTAR, master mode only. More...

DMA
void	dspi_hal_configure_dma (uint32_t instance, bool enableTransmit, bool enableReceive)
	Configures transmit and receive DMA requests. More...

Low power
static void	dspi_hal_configure_doze_mode (uint32_t instance, bool enable)
	Configures the DSPI operation during doze mode. More...

Interrupts
void	dspi_hal_configure_interrupt (uint32_t instance, dspi_status_and_interrupt_request_t interruptSrc, bool enable)
	Configures the DSPI interrupts. More...

static bool	dspi_hal_get_interrupt_config (uint32_t instance, dspi_status_and_interrupt_request_t interruptSrc)
	Gets the DSPI interrupt configuration, returns if interrupt request is enabled or disabled. More...

Status
static bool	dspi_hal_get_status_flag (uint32_t instance, dspi_status_and_interrupt_request_t statusFlag)
	Gets the DSPI status flag state. More...

static void	dspi_hal_clear_status_flag (uint32_t instance, dspi_status_and_interrupt_request_t statusFlag)
	Clears the DSPI status flag. More...

static uint32_t	dspi_hal_get_fifo_counter_or_pointer (uint32_t instance, dspi_fifo_counter_pointer_t desiredParameter)
	Gets the DSPI FIFO counter or pointer. More...

Data transfer
static uint32_t	dspi_hal_read_data (uint32_t instance)
	Reads data from the data buffer. More...

static void	dspi_hal_write_data_slave_mode (uint32_t instance, uint32_t data)
	Writes data into the data buffer, slave mode. More...

Data Structure Documentation

struct dspi_data_format_config_t

This structure contains the data format settings. These settings apply to a specific CTARn register, which the user must provide in this structure.

Data Fields
uint32_t	bitsPerFrame
	Bits per frame, minimum 4, maximum 16 (master), 32 (slave)

dspi_clock_polarity_t	clkPolarity
	Active high or low clock polarity.

dspi_clock_phase_t	clkPhase
	Clock phase setting to change and capture data.

dspi_shift_direction_t	direction
	MSB or LSB data shift direction This setting relevant only in master mode and can be ignored in slave mode.

struct dspi_master_config_t

Use an instance of this structure with the dspi_hal_master_init() to configure the most common settings of the DSPI peripheral in master mode with a single function call.

The bitsPerSec member is handled in a special way. If this value is set to 0, then the baud is not set by the dspi_hal_master_init(), and must be set with a separate call to either the dspi_hal_set_baud() or the dspi_hal_set_baud_divisors(). This can be useful when you know the divisors in advance and don't want to spend the time to compute them for the provided rate in bits/sec.

This structure also contains another structure template as a member: dspi_data_format_config_t dataConfig. An example usage for this is assuming declaration dspi_master_config_t dspiConfig:

dspiConfig.dataConfig.bitsPerFrame = 16;
dspiConfig.dataConfig.clkPolarity = kDspiClockPolarity_ActiveHigh;
dspiConfig.dataConfig.clkPhase = kDspiClockPhase_FirstEdge;
dspiConfig.dataConfig.direction = kDspiMsbFirst;

Data Fields
bool	isEnabled
	Set to true to enable the DSPI peripheral. More...

dspi_ctar_selection_t	whichCtar
	Desired Clock and Transfer Attributes Register (CTAR)

uint32_t	bitsPerSec
	Baud rate in bits per second.

uint32_t	sourceClockInHz
	Module source clock.

dspi_data_format_config_t	dataConfig
	Data format configuration structure.

bool	isSckContinuous
	Disable(0) or Enable(1) continuous SCK operation.

dspi_which_pcs_config_t	whichPcs
	Desired Peripheral Chip Select (PCS)

dspi_pcs_polarity_config_t	pcsPolarity
	Peripheral Chip Select (PCS) polarity setting. More...

dspi_master_sample_point_t	masterInSample
	Master data-in (SIN) sample point setting. More...

bool	isModifiedTimingFormatEnabled
	Disable(0) or Enable(1) modified timing format. More...

bool	isTxFifoDisabled
	Disable(1) or Enable(0) Tx FIFO.

bool	isRxFifoDisabled
	Disable(1) or Enable(0) Rx FIFO.

struct dspi_slave_config_t

Use an instance of this structure with the dspi_hal_slave_init() to configure the most common settings of the DSPI peripheral in slave mode with a single function call.

Data Fields
bool	isEnabled
	Set to true to enable the DSPI peripheral. More...

dspi_data_format_config_t	dataConfig
	Data format configuration structure.

bool	isTxFifoDisabled
	Disable(1) or Enable(0) Tx FIFO.

bool	isRxFifoDisabled
	Disable(1) or Enable(0) Rx FIFO.

struct dspi_baud_rate_divisors_t

Note: These settings are relevant only in master mode. This structure contains the baud rate divisor settings, which provides the user with the option to explicitly set these baud rate divisors. In addition, the user must also set the CTARn register with the divisor settings.

Data Fields
bool	doubleBaudRate
	Double Baud rate parameter setting.

uint32_t	prescaleDivisor
	Baud Rate Pre-scalar parameter setting.

uint32_t	baudRateDivisor
	Baud Rate scaler parameter setting.

struct dspi_delay_settings_config_t

Note: These settings are relevant only in master mode. This structure contains the various delay settings. These settings apply to a specific CTARn register, which the user must provide in this structure.

Data Fields
uint32_t	pcsToSckPre
	PCS to SCK delay pre-scalar (PCSSCK)

uint32_t	pcsToSck
	PCS to SCK Delay scalar (CSSCK)

uint32_t	afterSckPre
	After SCK delay pre-scalar (PASC)

uint32_t	afterSck
	After SCK delay scalar (ASC)

uint32_t	afterTransferPre
	Delay after transfer pre-scalar (PDT)

uint32_t	afterTransfer
	Delay after transfer scalar (DT)

struct dspi_command_config_t

Note: This structure is used with the PUSHR register, which provides the means to write to the Tx FIFO. Data written to this register is transferred to the Tx FIFO. Eight or sixteen-bit write accesses to the PUSHR transfer all 32 register bits to the Tx FIFO. The register structure is different in master and slave modes. In master mode, the register provides 16-bit command and 16-bit data to the Tx FIFO. In slave mode all 32 register bits can be used as data, supporting up to 32-bit SPI frame operation.

Data Fields
bool	isChipSelectContinuous
	Option to enable the continuous assertion of chip select between transfers.

dspi_ctar_selection_t	whichCtar
	The desired Clock and Transfer Attributes Register (CTAR) to use for CTAS.

dspi_which_pcs_config_t	whichPcs
	The desired PCS signal to use for the data transfer.

bool	isEndOfQueue
	Signals that the current transfer is the last in the queue.

bool	clearTransferCount
	Clears SPI_TCNT field; cleared before transmission starts.

Enumeration Type Documentation

enum dspi_status_t

Enumerator
kStatus_DSPI_SlaveTxUnderrun	DSPI Slave Tx Under run error.
kStatus_DSPI_SlaveRxOverrun	DSPI Slave Rx Overrun error.
kStatus_DSPI_Timeout	DSPI transfer timed out.
kStatus_DSPI_Busy	DSPI instance is already busy performing a transfer.
kStatus_DSPI_NoTransferInProgress	Attempt to abort a transfer when no transfer was in progress.
kStatus_DSPI_InvalidBitCount	bits-per-frame value not valid
kStatus_DSPI_InvalidInstanceNumber	DSPI instance number does not match current count.

enum dspi_master_slave_mode_t

Enumerator
kDspiMaster	DSPI peripheral operates in master mode.
kDspiSlave	DSPI peripheral operates in slave mode.

enum dspi_clock_polarity_t

Enumerator
kDspiClockPolarity_ActiveHigh	Active-high DSPI clock (idles low)
kDspiClockPolarity_ActiveLow	Active-low DSPI clock (idles high)

enum dspi_clock_phase_t

Enumerator
kDspiClockPhase_FirstEdge	Data is captured on the leading edge of the SCK and changed on the following edge.
kDspiClockPhase_SecondEdge	Data is changed on the leading edge of the SCK and captured on the following edge.

enum dspi_shift_direction_t

Enumerator
kDspiMsbFirst	Data transfers start with most significant bit.
kDspiLsbFirst	Data transfers start with least significant bit.

enum dspi_ctar_selection_t

Enumerator
kDspiCtar0	CTAR0 selection option for master or slave mode.
kDspiCtar1	CTAR1 selection option for master mode only.

enum dspi_pcs_polarity_config_t

Enumerator
kDspiPcs_ActiveHigh	PCS Active High (idles low)
kDspiPcs_ActiveLow	PCS Active Low (idles high)

enum dspi_which_pcs_config_t

Enumerator
kDspiPcs0	PCS[0].
kDspiPcs1	PCS[1].
kDspiPcs2	PCS[2].
kDspiPcs3	PCS[3].
kDspiPcs4	PCS[4].
kDspiPcs5	PCS[5].

enum dspi_master_sample_point_t

This field is valid only when CPHA bit in CTAR register is 0.

Enumerator
kDspiSckToSin_0Clock	0 system clocks between SCK edge and SIN sample
kDspiSckToSin_1Clock	1 system clock between SCK edge and SIN sample
kDspiSckToSin_2Clock	2 system clocks between SCK edge and SIN sample

enum dspi_fifo_t

Enumerator
kDspiTxFifo	DSPI Tx FIFO.
kDspiRxFifo	DSPI Rx FIFO.

enum dspi_status_and_interrupt_request_t

Enumerator
kDspiTxComplete	TCF status/interrupt enable.
kDspiTxAndRxStatus	TXRXS status only, no interrupt.
kDspiEndOfQueue	EOQF status/interrupt enable.
kDspiTxFifoUnderflow	TFUF status/interrupt enable.
kDspiTxFifoFillRequest	TFFF status/interrupt enable.
kDspiRxFifoOverflow	RFOF status/interrupt enable.
kDspiRxFifoDrainRequest	RFDF status/interrupt enable.

enum dspi_fifo_counter_pointer_t

Enumerator
kDspiRxFifoPointer	Rx FIFO pointer.
kDspiRxFifoCounter	Rx FIFO counter.
kDspiTxFifoPointer	Tx FIFO pointer.
kDspiTxFifoCounter	Tx FIFO counter.

Function Documentation

dspi_status_t dspi_hal_master_init	(	uint32_t	instance,
		const dspi_master_config_t *	config,
		uint32_t *	calculatedBaudRate
	)

This function initializes the module to the user defined settings and default settings in master mode. This is an example demonstrating how to define the dspi_master_config_t structure and call the dspi_hal_master_init function:

dspi_master_config_t dspiConfig;
dspiConfig.isEnabled = false;
dspiConfig.whichCtar = kDspiCtar0;
dspiConfig.bitsPerSec = 0;
dspiConfig.sourceClockInHz = dspiSourceClock;
dspiConfig.isSckContinuous = false;
dspiConfig.whichPcs = kDspiPcs0;
dspiConfig.pcsPolarity = kDspiPcs_ActiveLow;
dspiConfig.masterInSample = kDspiSckToSin_0Clock;
dspiConfig.isModifiedTimingFormatEnabled = false;
dspiConfig.isTxFifoDisabled = false;
dspiConfig.isRxFifoDisabled = false;
dspiConfig.dataConfig.bitsPerFrame = 16;
dspiConfig.dataConfig.clkPolarity = kDspiClockPolarity_ActiveHigh;
dspiConfig.dataConfig.clkPhase = kDspiClockPhase_FirstEdge;
dspiConfig.dataConfig.direction = kDspiMsbFirst;
dspi_hal_master_init(instance, &dspiConfig, calculatedBaudRate);

Parameters

instance	Module instance number
config	Pointer to the master mode configuration data structure
calculatedBaudRate	The calculated baud rate passed back to the user for them to determine if the calculated baud rate is close enough to meet their needs.

Returns: An error code or kStatus_DSPI_Success.

dspi_status_t dspi_hal_slave_init	(	uint32_t	instance,
		const dspi_slave_config_t *	config
	)

This function initializes the DSPI module for slave mode. This is an example demonstrating how to define the dspi_slave_config_t structure and call the dspi_hal_slave_init function:

dspi_slave_config_t dspiConfig;
dspiConfig.isEnabled = false;
dspiConfig.isTxFifoDisabled = false;
dspiConfig.isRxFifoDisabled = false;
dspiConfig.dataConfig.bitsPerFrame = 16;
dspiConfig.dataConfig.clkPolarity = kDspiClockPolarity_ActiveHigh;
dspiConfig.dataConfig.clkPhase = kDspiClockPhase_FirstEdge;
dspi_hal_slave_init(instance, &dspiConfig);

Parameters

instance	Module instance number
config	Pointer to the slave mode configuration data structure

Returns: An error code or kStatus_DSPI_Success.

void dspi_hal_reset ( uint32_t instance )

This function basically resets all of the DSPI registers to their default setting including disabling the module.

Parameters

instance Module instance number

static void dspi_hal_enable ( uint32_t instance )

inlinestatic

Parameters

instance Module instance number

static void dspi_hal_disable ( uint32_t instance )

inlinestatic

Parameters

instance Module instance number

uint32_t dspi_hal_set_baud	(	uint32_t	instance,
		dspi_ctar_selection_t	whichCtar,
		uint32_t	bitsPerSec,
		uint32_t	sourceClockInHz
	)

This function takes in the desired bitsPerSec (baud rate) and calculates the nearest possible baud rate without exceeding the desired baud rate, and returns the calculated baud rate in bits-per-second. It requires that the caller also provide the frequency of the module source clock (in Hertz).

Parameters

instance	Module instance number
whichCtar	The desired Clock and Transfer Attributes Register (CTAR) of the type dspi_ctar_selection_t
bitsPerSec	The desired baud rate in bits per second
sourceClockInHz	Module source input clock in Hertz

Returns: The actual calculated baud rate

void dspi_hal_set_baud_divisors	(	uint32_t	instance,
		dspi_ctar_selection_t	whichCtar,
		const dspi_baud_rate_divisors_t *	divisors
	)

This function allows the caller to manually set the baud rate divisors in the event that these dividers are known and the caller does not wish to call the dspi_hal_set_baud function.

Parameters

instance	Module instance number
whichCtar	The desired Clock and Transfer Attributes Register (CTAR) of type dspi_ctar_selection_t
divisors	Pointer to a structure containing the user defined baud rate divisor settings

static void dspi_hal_set_master_slave	(	uint32_t	instance,
		dspi_master_slave_mode_t	mode
	)

inlinestatic

Parameters

instance	Module instance number
mode	Mode setting (master or slave) of type dspi_master_slave_mode_t

static void dspi_hal_configure_continuous_sck	(	uint32_t	instance,
		bool	enable
	)

inlinestatic

Parameters

instance	Module instance number
enable	Enables (true) or disables(false) continuous SCK operation.

static void dspi_hal_configure_modified_timing_format	(	uint32_t	instance,
		bool	enable
	)

inlinestatic

Parameters

instance	Module instance number
enable	Enables (true) or disables(false) modified timing format.

static void dspi_hal_configure_pcs_strobe	(	uint32_t	instance,
		bool	enable
	)

inlinestatic

Configures the PCS[5] to be the active-low PCS Strobe output.

PCS[5] is a special case that can be configured as an active low PCS strobe or as a Peripheral Chip Select in master mode. When configured as a strobe, it provides a signal to an external demultiplexer to decode PCS[0] to PCS[4] signals into as many as 128 glitch-free PCS signals.

Parameters

instance	Module instance number
enable	Enable (true) PCS[5] to operate as the peripheral chip select (PCS) strobe If disable (false), PCS[5] operates as a peripheral chip select

static void dspi_hal_configure_rx_fifo_overwrite	(	uint32_t	instance,
		bool	enable
	)

inlinestatic

When enabled, this function allows incoming receive data to overwrite the existing data in the receive shift register when the Rx FIFO is full. Otherwise when disabled, the incoming data is ignored when the RX FIFO is full.

Parameters

instance	Module instance number.
enable	If enabled (true), allows incoming data to overwrite Rx FIFO contents when full, else incoming data is ignored.

void dspi_hal_configure_pcs_polarity	(	uint32_t	instance,
		dspi_which_pcs_config_t	pcs,
		dspi_pcs_polarity_config_t	activeLowOrHigh
	)

This function takes in the desired peripheral chip select (PCS) and it's corresponding desired polarity and configures the PCS signal to operate with the desired characteristic.

Parameters

instance	Module instance number
pcs	The particular peripheral chip select (parameter value is of type dspi_which_pcs_config_t) for which we wish to apply the active high or active low characteristic.
activeLowOrHigh	The setting for either "active high, inactive low (0)" or "active low, inactive high(1)" of type dspi_pcs_polarity_config_t.

void dspi_hal_configure_fifos	(	uint32_t	instance,
		bool	disableTxFifo,
		bool	disableRxFifo
	)

This function allows the caller to disable/enable the Tx and Rx FIFOs (independently). Note that to disable, the caller must pass in a logic 1 (true) for the particular FIFO configuration. To enable, the caller must pass in a logic 0 (false). For example, to enable both the Tx and Rx FIFOs, the caller makes this function call (where instance is the desired module instance number):

dspi_hal_configure_fifos(instance, false, false);

Parameters

instance	Module instance number
disableTxFifo	Disables (false) the TX FIFO, else enables (true) the TX FIFO
disableRxFifo	Disables (false) the RX FIFO, else enables (true) the RX FIFO

void dspi_hal_flush_fifos	(	uint32_t	instance,
		bool	enableFlushTxFifo,
		bool	enableFlushRxFifo
	)

Parameters

instance	Module instance number
enableFlushTxFifo	Flushes (true) the Tx FIFO, else do not flush (false) the Tx FIFO
enableFlushRxFifo	Flushes (true) the Rx FIFO, else do not flush (false) the Rx FIFO

static void dspi_hal_set_datain_samplepoint	(	uint32_t	instance,
		dspi_master_sample_point_t	samplePnt
	)

inlinestatic

This function controls when the DSPI master samples SIN (data in) in the Modified Transfer Format. Note that this is valid only when the CPHA bit in the CTAR register is 0.

Parameters

instance	Module instance number
samplePnt	selects when the data in (SIN) is sampled, of type dspi_master_sample_point_t. This value selects either 0, 1, or 2 system clocks between the SCK edge and the SIN (data in) sample.

static void dspi_hal_start_transfer ( uint32_t instance )

inlinestatic

This function call called whenever the module is ready to begin data transfers in either master or slave mode.

Parameters

instance Module instance number

static void dspi_hal_stop_transfer ( uint32_t instance )

inlinestatic

This function call stops data transfers in either master or slave mode.

Parameters

instance Module instance number

dspi_status_t dspi_hal_configure_data_format	(	uint32_t	instance,
		dspi_ctar_selection_t	whichCtar,
		const dspi_data_format_config_t *	config
	)

This function configures the bits-per-frame, polarity, phase, and shift direction for a particular CTAR. An example use case is as follows:

dspi_data_format_config_t dataFormat;
dataFormat.bitsPerFrame = 16;
dataFormat.clkPolarity = kDspiClockPolarity_ActiveLow;
dataFormat.clkPhase = kDspiClockPhase_FirstEdge;
dataFormat.direction = kDspiMsbFirst;
dspi_hal_configure_data_format(instance, kDspiCtar0, &dataFormat);

Parameters

instance	Module instance number
whichCtar	The desired Clock and Transfer Attributes Register (CTAR) of type dspi_ctar_selection_t.
config	Pointer to a structure containing the user defined data format configuration settings.

Returns: An error code or kStatus_DSPI_Success

void dspi_hal_configure_delays	(	uint32_t	instance,
		dspi_ctar_selection_t	whichCtar,
		const dspi_delay_settings_config_t *	config
	)

This function configures the PCS to SCK delay pre-scalar (PCSSCK), the PCS to SCK Delay scalar (CSSCK), the After SCK delay pre-scalar (PASC), the After SCK delay scalar (ASC), the Delay after transfer pre-scalar (PDT), and the Delay after transfer scalar (DT). The following is an example use case of this function:

   dspi_delay_settings_config_t delayConfig;
   delayConfig.pcsToSckPre = 0x3;
   delayConfig.pcsToSck = 0xF;
   delayConfig.afterSckPre = 0x2;
   delayConfig.afterSck = 0xA;
   delayConfig.afterTransferPre = 0x1;
   delayConfig.afterTransfer = 0x5;
   dspi_hal_configure_delays(instance, kDspiCtar0, &delayConfig);
* 

Parameters

instance	Module instance number
whichCtar	The desired Clock and Transfer Attributes Register (CTAR) of type dspi_ctar_selection_t.
config	Pointer to a structure containing the user defined delay configuration settings.

void dspi_hal_configure_dma	(	uint32_t	instance,
		bool	enableTransmit,
		bool	enableReceive
	)

This function configures the FIFOs to generate a DMA or an interrupt request. Note that the corresponding request enable must also be set. For the Transmit FIFO Fill, in order to generate a DMA request, the Transmit FIFO Fill Request Enable (TFFF_RE) must also be set. Similarly for the Receive FIFO Drain Request, to generate a DMA request, the Receive FIFO Drain Request Enable (RFDF_RE) must also be set. These requests can be configured with the function dspi_hal_configure_interrupt(). To enable DMA operation, first enable the desired request enable by using the dspi_hal_configure_interrupt() function and then use the dspi_hal_configure_dma() to configure the request and generate a DMA request.

Parameters

enableTransmit	Configures Tx FIFO fill request to generate a DMA or interrupt request
enableReceive	Configures Rx FIFO fill request to generate a DMA or interrupt request

static void dspi_hal_configure_doze_mode	(	uint32_t	instance,
		bool	enable
	)

inlinestatic

This function provides support for an externally controlled doze mode, power-saving, mechanism. When disabled, the doze mode has no effect on the DSPI, and when enabled, the Doze mode disables the DSPI.

Parameters

instance	Module instance number
enable	If disabled (false), the doze mode has no effect on the DSPI, if enabled (true), the doze mode disables the DSPI.

void dspi_hal_configure_interrupt	(	uint32_t	instance,
		dspi_status_and_interrupt_request_t	interruptSrc,
		bool	enable
	)

This function configures the various interrupt sources of the DSPI. The parameters are instance, interrupt source, and enable/disable setting. The interrupt source is a typedef enum whose value is the bit position of the interrupt source setting within the RSER register. In the DSPI, all interrupt configuration settings are in one register. The typedef enum equates each interrupt source to the bit position defined in the device header file. The function uses these bit positions in its algorithm to enable/disable the interrupt source, where interrupt source is the dspi_status_and_interrupt_request_t type.

   temp = (HW_SPI_RSER_RD(instance) & ~interruptSrc) | (enable << interruptSrc);
   HW_SPI_RSER_WR(instance, temp);
   dspi_hal_configure_interrupt(instance, kDspiTxComplete, true); <- example use-case
* 

Parameters

instance	Module instance number
interruptSrc	The interrupt source, of type dspi_status_and_interrupt_request_t
enable	Enable (true) or disable (false) the interrupt source to generate requests

static bool dspi_hal_get_interrupt_config	(	uint32_t	instance,
		dspi_status_and_interrupt_request_t	interruptSrc
	)

inlinestatic

This function returns the requested interrupt source setting (enabled or disabled, of type bool). The parameters to pass in are instance and interrupt source. It utilizes the same enum definitions for the interrupt sources as described in the "interrupt configuration" function. The function uses these bit positions in its algorithm to obtain the desired interrupt source setting.

   return ((HW_SPI_RSER_RD(instance) & interruptSrc) >> interruptSrc);
  getInterruptSetting = dspi_hal_get_interrupt_config(instance, kDspiTxComplete);
* 

Parameters

instance	Module instance number
interruptSrc	The interrupt source, of type dspi_status_and_interrupt_request_t

Returns: Configuration of interrupt request: enable (true) or disable (false).

static bool dspi_hal_get_status_flag	(	uint32_t	instance,
		dspi_status_and_interrupt_request_t	statusFlag
	)

inlinestatic

The status flag is defined in the same enum as the interrupt source enable because the bit position of the interrupt source and corresponding status flag are the same in the RSER and SR registers. The function uses these bit positions in its algorithm to obtain the desired flag state, similar to the dspi_get_interrupt_config function.

   return ((HW_SPI_SR_RD(instance) & statusFlag) >> statusFlag);
   getStatus = dspi_hal_get_status_flag(instance, kDspiTxComplete);
* 

Parameters

instance	Module instance number
statusFlag	The status flag, of type dspi_status_and_interrupt_request_t

Returns: State of the status flag: asserted (true) or not-asserted (false)

static void dspi_hal_clear_status_flag	(	uint32_t	instance,
		dspi_status_and_interrupt_request_t	statusFlag
	)

inlinestatic

This function clears the desired status bit by using a write-1-to-clear. The user passes in the instance and the desired status bit to clear. The list of status bits is defined in the dspi_status_and_interrupt_request_t. The function uses these bit positions in its algorithm to clear the desired flag state. It uses this macro:

   HW_SPI_SR_WR(instance, statusFlag);
   dspi_hal_clear_status_flag(instance, kDspiTxComplete);
* 

Parameters

instance	Module instance number
statusFlag	The status flag, of type dspi_status_and_interrupt_request_t

static uint32_t dspi_hal_get_fifo_counter_or_pointer	(	uint32_t	instance,
		dspi_fifo_counter_pointer_t	desiredParameter
	)

inlinestatic

This function returns the number of entries or the next pointer in the Tx or Rx FIFO. The parameters to pass in are the instance and either the Tx or Rx FIFO counter or a pointer. The latter is an enum type defined as the bitmask of those particular bit fields found in the device header file. For example:

   return ((HW_SPI_SR_RD(instance) >> desiredParamter) & 0xF);
   dspi_hal_get_fifo_counter_or_pointer(instance, kDspiRxFifoCounter);
* 

Parameters

instance	Module instance number
desiredParameter	Desired parameter to obtain, of type dspi_fifo_counter_pointer_t

static uint32_t dspi_hal_read_data ( uint32_t instance )

inlinestatic

Parameters

instance Module instance number

static void dspi_hal_write_data_slave_mode	(	uint32_t	instance,
		uint32_t	data
	)

inlinestatic

In slave mode, up to 32-bit words may be written.

Parameters

instance	Module instance number
data	The data to send

Variable Documentation

const uint32_t s_baudrateScaler[]

static

Initial value:

= { 2, 4, 6, 8, 16, 32, 64, 128, 256, 512, 1024, 2048,

4096, 8192, 16384, 32768 }

bool dspi_master_config_t::isEnabled

dspi_pcs_polarity_config_t dspi_master_config_t::pcsPolarity

dspi_master_sample_point_t dspi_master_config_t::masterInSample

bool dspi_master_config_t::isModifiedTimingFormatEnabled

bool dspi_slave_config_t::isEnabled

Data Structures

Enumerations

Variables

Configuration

DMA

Low power

Interrupts

Status

Data transfer

Data Structure Documentation

Data Fields

Data Fields

Data Fields

Data Fields

Data Fields

Data Fields

Enumeration Type Documentation

Function Documentation

Variable Documentation