Overview

This section describes the programming interface of the SPI HAL driver.

Files
file	fsl_spi_hal.h

Enumerations
enum	spi_status_t { , kStatus_SPI_SlaveTxUnderrun, kStatus_SPI_SlaveRxOverrun, kStatus_SPI_Timeout, kStatus_SPI_Busy, kStatus_SPI_NoTransferInProgress, kStatus_SPI_OutOfRange, kStatus_SPI_TxBufferNotEmpty, kStatus_SPI_InvalidParameter, kStatus_SPI_NonInit, kStatus_SPI_AlreadyInitialized, kStatus_SPI_DMAChannelInvalid, kStatus_SPI_Error }
	Error codes for the SPI driver. More...

enum	spi_master_slave_mode_t { kSpiMaster = 1, kSpiSlave = 0 }
	SPI master or slave configuration. More...

enum	spi_clock_polarity_t { kSpiClockPolarity_ActiveHigh = 0, kSpiClockPolarity_ActiveLow = 1 }
	SPI clock polarity configuration. More...

enum	spi_clock_phase_t { kSpiClockPhase_FirstEdge = 0, kSpiClockPhase_SecondEdge = 1 }
	SPI clock phase configuration. More...

enum	spi_shift_direction_t { kSpiMsbFirst = 0, kSpiLsbFirst = 1 }
	SPI data shifter direction options. More...

enum	spi_ss_output_mode_t { kSpiSlaveSelect_AsGpio = 0, kSpiSlaveSelect_FaultInput = 2, kSpiSlaveSelect_AutomaticOutput = 3 }
	SPI slave select output mode options. More...

enum	spi_pin_mode_t { kSpiPinMode_Normal = 0, kSpiPinMode_Input = 1, kSpiPinMode_Output = 3 }
	SPI pin mode options. More...

enum	spi_data_bitcount_mode_t { kSpi8BitMode = 0, kSpi16BitMode = 1 }
	SPI data length mode options. More...

enum	spi_interrupt_source_t { kSpiRxFullAndModfInt = 1, kSpiTxEmptyInt = 2, kSpiMatchInt = 3 }
	SPI interrupt sources. More...

enum	spi_int_status_flag_t { kSpiRxBufferFullFlag = SPI_S_SPRF_SHIFT, kSpiMatchFlag = SPI_S_SPMF_SHIFT, kSpiTxBufferEmptyFlag = SPI_S_SPTEF_SHIFT, kSpiModeFaultFlag = SPI_S_MODF_SHIFT }
	SPI interrupt status flags. More...

enum	spi_fifo_interrupt_source_t { kSpiRxFifoNearFullInt = 1, kSpiTxFifoNearEmptyInt = 2 }
	SPI FIFO interrupt sources. More...

enum	spi_w1c_interrupt_t { kSpiRxFifoFullClearInt = 0, kSpiTxFifoEmptyClearInt = 1, kSpiRxNearFullClearInt = 2, kSpiTxNearEmptyClearInt = 3 }
	SPI FIFO write-1-to-clear interrupt flags. More...

enum	spi_txfifo_watermark_t
	SPI TX FIFO watermark settings. More...

enum	spi_rxfifo_watermark_t
	SPI RX FIFO watermark settings. More...

enum	spi_fifo_status_flag_t
	SPI status flags. More...

enum	spi_fifo_error_flag_t { kSpiNoFifoError = 0, kSpiRxfof = 1, kSpiTxfof = 2, kSpiRxfofTxfof = 3, kSpiRxferr = 4, kSpiRxfofRxferr = 5, kSpiTxfofRxferr = 6, kSpiRxfofTxfofRxferr = 7, kSpiTxferr = 8, kSpiRxfofTxferr = 9, kSpiTxfofTxferr = 10, kSpiRxfofTxfofTxferr = 11, kSpiRxferrTxferr = 12, kSpiRxfofRxferrTxferr = 13, kSpiTxfofRxferrTxferr = 14, kSpiRxfofTxfofRxferrTxferr =15 }
	SPI error flags. More...

Configuration
void	SPI_HAL_Init (SPI_Type *base)
	Restores the SPI to the reset configuration. More...

static void	SPI_HAL_Enable (SPI_Type *base)
	Enables the SPI peripheral. More...

static void	SPI_HAL_Disable (SPI_Type *base)
	Disables the SPI peripheral. More...

uint32_t	SPI_HAL_SetBaud (SPI_Type *base, uint32_t bitsPerSec, uint32_t sourceClockInHz)
	Sets the SPI baud rate in bits per second. More...

static void	SPI_HAL_SetBaudDivisors (SPI_Type *base, uint32_t prescaleDivisor, uint32_t rateDivisor)
	Configures the baud rate divisors manually. More...

static void	SPI_HAL_SetMasterSlave (SPI_Type *base, spi_master_slave_mode_t mode)
	Configures the SPI for master or slave. More...

static bool	SPI_HAL_IsMaster (SPI_Type *base)
	Returns whether the SPI module is in master mode. More...

void	SPI_HAL_SetSlaveSelectOutputMode (SPI_Type *base, spi_ss_output_mode_t mode)
	Sets how the slave select output operates. More...

void	SPI_HAL_SetDataFormat (SPI_Type *base, spi_clock_polarity_t polarity, spi_clock_phase_t phase, spi_shift_direction_t direction)
	Sets the polarity, phase, and shift direction. More...

static uint32_t	SPI_HAL_GetDataRegAddr (SPI_Type *base)
	Gets the SPI data register address for DMA operation. More...

void	SPI_HAL_SetPinMode (SPI_Type *base, spi_pin_mode_t mode)
	Sets the SPI pin mode. More...

Interrupts
void	SPI_HAL_SetIntMode (SPI_Type *base, spi_interrupt_source_t interrupt, bool enable)
	Enables or disables the SPI interrupts. More...

static void	SPI_HAL_SetReceiveAndFaultIntCmd (SPI_Type *base, bool enable)
	Enables or disables the SPI receive buffer/FIFO full and mode fault interrupt. More...

static void	SPI_HAL_SetTransmitIntCmd (SPI_Type *base, bool enable)
	Enables or disables the SPI transmit buffer/FIFO empty interrupt. More...

static void	SPI_HAL_SetMatchIntCmd (SPI_Type *base, bool enable)
	Enables or disables the SPI match interrupt. More...

Status
static bool	SPI_HAL_GetIntStatusFlag (SPI_Type *base, spi_int_status_flag_t flag)
	Gets the SPI interrupt status flag state. More...

static bool	SPI_HAL_IsReadBuffFullPending (SPI_Type *base)
	Checks whether the read buffer/FIFO is full. More...

static bool	SPI_HAL_IsTxBuffEmptyPending (SPI_Type *base)
	Checks whether the transmit buffer/FIFO is empty. More...

static bool	SPI_HAL_IsModeFaultPending (SPI_Type *base)
	Checks whether a mode fault occurred. More...

void	SPI_HAL_ClearModeFaultFlag (SPI_Type *base)
	Clears the mode fault flag. More...

static bool	SPI_HAL_IsMatchPending (SPI_Type *base)
	Checks whether the data received matches the previously-set match value. More...

void	SPI_HAL_ClearMatchFlag (SPI_Type *base)
	Clears the match flag. More...

Data transfer
static uint8_t	SPI_HAL_ReadData (SPI_Type *base)
	Reads a byte from the data buffer. More...

static void	SPI_HAL_WriteData (SPI_Type *base, uint8_t data)
	Writes a byte into the data buffer. More...

void	SPI_HAL_WriteDataBlocking (SPI_Type *base, uint8_t data)
	Writes a byte into the data buffer and waits till complete to return. More...

Match byte
static void	SPI_HAL_SetMatchValue (SPI_Type *base, uint8_t matchByte)
	Sets the value which triggers the match interrupt. More...

Enumeration Type Documentation

enum spi_status_t

Enumerator
kStatus_SPI_SlaveTxUnderrun	SPI Slave TX Underrun error.
kStatus_SPI_SlaveRxOverrun	SPI Slave RX Overrun error.
kStatus_SPI_Timeout	SPI transfer timed out.
kStatus_SPI_Busy	SPI instance is already busy performing a transfer.
kStatus_SPI_NoTransferInProgress	Attempt to abort a transfer when no transfer was in progress.
kStatus_SPI_OutOfRange	SPI out-of-range error used in slave callback.
kStatus_SPI_TxBufferNotEmpty	SPI TX buffer register is not empty.
kStatus_SPI_InvalidParameter	Parameter is invalid.
kStatus_SPI_NonInit	SPI driver is not initialized.
kStatus_SPI_AlreadyInitialized	SPI driver already initialized.
kStatus_SPI_DMAChannelInvalid	SPI driver cannot requests DMA channel.
kStatus_SPI_Error	SPI driver error.

enum spi_master_slave_mode_t

Enumerator
kSpiMaster	SPI peripheral operates in master mode.
kSpiSlave	SPI peripheral operates in slave mode.

enum spi_clock_polarity_t

Enumerator
kSpiClockPolarity_ActiveHigh	Active-high SPI clock (idles low).
kSpiClockPolarity_ActiveLow	Active-low SPI clock (idles high).

enum spi_clock_phase_t

Enumerator
kSpiClockPhase_FirstEdge	First edge on SPSCK occurs at the middle of the first cycle of a data transfer.
kSpiClockPhase_SecondEdge	First edge on SPSCK occurs at the start of the first cycle of a data transfer.

enum spi_shift_direction_t

Enumerator
kSpiMsbFirst	Data transfers start with most significant bit.
kSpiLsbFirst	Data transfers start with least significant bit.

enum spi_ss_output_mode_t

Enumerator
kSpiSlaveSelect_AsGpio	Slave select pin configured as GPIO.
kSpiSlaveSelect_FaultInput	Slave select pin configured for fault detection.
kSpiSlaveSelect_AutomaticOutput	Slave select pin configured for automatic SPI output.

enum spi_pin_mode_t

Enumerator

kSpiPinMode_Normal

Pins operate in normal, single-direction mode.

kSpiPinMode_Input

Bidirectional mode.

Master: MOSI pin is input; Slave: MISO pin is input

kSpiPinMode_Output

Bidirectional mode.

Master: MOSI pin is output; Slave: MISO pin is output

enum spi_data_bitcount_mode_t

Enumerator
kSpi8BitMode	8-bit data transmission mode
kSpi16BitMode	16-bit data transmission mode

enum spi_interrupt_source_t

Enumerator
kSpiRxFullAndModfInt	Receive buffer full (SPRF) and mode fault (MODF) interrupt.
kSpiTxEmptyInt	Transmit buffer empty interrupt.
kSpiMatchInt	Match interrupt.

enum spi_int_status_flag_t

Enumerator
kSpiRxBufferFullFlag	Read buffer full flag.
kSpiMatchFlag	Match flag.
kSpiTxBufferEmptyFlag	Transmit buffer empty flag.
kSpiModeFaultFlag	Mode fault flag.

enum spi_fifo_interrupt_source_t

Enumerator
kSpiRxFifoNearFullInt	Receive FIFO nearly full interrupt.
kSpiTxFifoNearEmptyInt	Transmit FIFO nearly empty interrupt.

enum spi_w1c_interrupt_t

Enumerator
kSpiRxFifoFullClearInt	Receive FIFO full interrupt.
kSpiTxFifoEmptyClearInt	Transmit FIFO empty interrupt.
kSpiRxNearFullClearInt	Receive FIFO nearly full interrupt.
kSpiTxNearEmptyClearInt	Transmit FIFO nearly empty interrupt.

enum spi_txfifo_watermark_t

enum spi_rxfifo_watermark_t

enum spi_fifo_status_flag_t

enum spi_fifo_error_flag_t

Enumerator
kSpiNoFifoError	No error is detected.
kSpiRxfof	Receive FIFO Overflow.
kSpiTxfof	Transmit FIFO Overflow.
kSpiRxfofTxfof	Receive FIFO Overflow, Transmit FIFO Overflow.
kSpiRxferr	Receive FIFO Error.
kSpiRxfofRxferr	Receive FIFO Overflow, Receive FIFO Error.
kSpiTxfofRxferr	Transmit FIFO Overflow, Receive FIFO Error.
kSpiRxfofTxfofRxferr	Receive FIFO Overflow, Transmit FIFO Overflow, Receive FIFO Error.
kSpiTxferr	Transmit FIFO Error.
kSpiRxfofTxferr	Receive FIFO Overflow, Transmit FIFO Error.
kSpiTxfofTxferr	Transmit FIFO Overflow, Transmit FIFO Error.
kSpiRxfofTxfofTxferr	Receive FIFO Overflow, Transmit FIFO Overflow, Transmit FIFO Error.
kSpiRxferrTxferr	Receive FIFO Error, Transmit FIFO Error.
kSpiRxfofRxferrTxferr	Receive FIFO Overflow, Receive FIFO Error, Transmit FIFO Error.
kSpiTxfofRxferrTxferr	Transmit FIFO Overflow, Receive FIFO Error, Transmit FIFO Error.
kSpiRxfofTxfofRxferrTxferr	Receive FIFO Overflow, Transmit FIFO Overflow Receive FIFO Error, Transmit FIFO Error.

Function Documentation

void SPI_HAL_Init ( SPI_Type * base )

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

Parameters

base	Module base pointer of type SPI_Type.

static void SPI_HAL_Enable ( SPI_Type * base )

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.

static void SPI_HAL_Disable ( SPI_Type * base )

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.

uint32_t SPI_HAL_SetBaud	(	SPI_Type *	base,
		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 unless the baud rate requested is less than the absolute minimum in which case the minimum baud rate is returned. The returned baud rate is in bits-per-second. It requires that the caller also provide the frequency of the module source clock (in Hertz).

Parameters

base	Module base pointer of type SPI_Type.
bitsPerSec	The desired baud rate in bits per second.
sourceClockInHz	Module source input clock in Hertz.

Returns: The actual calculated baud rate in Hz.

static void SPI_HAL_SetBaudDivisors	(	SPI_Type *	base,
		uint32_t	prescaleDivisor,
		uint32_t	rateDivisor
	)

inlinestatic

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 SPI_HAL_SetBaudRate function.

Parameters

base	Module base pointer of type SPI_Type.
prescaleDivisor	baud rate prescale divisor setting.
rateDivisor	baud rate divisor setting.

static void SPI_HAL_SetMasterSlave	(	SPI_Type *	base,
		spi_master_slave_mode_t	mode
	)

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.
mode	Mode setting (master or slave) of type dspi_master_slave_mode_t.

static bool SPI_HAL_IsMaster ( SPI_Type * base )

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.

Returns: true The module is in master mode. false The module is in slave mode.

void SPI_HAL_SetSlaveSelectOutputMode	(	SPI_Type *	base,
		spi_ss_output_mode_t	mode
	)

This function allows the user to configure the slave select in one of the three operational modes: as GPIO, as a fault input, or as an automatic output for standard SPI modes.

Parameters

base	Module base pointer of type SPI_Type.
mode	Selection input of one of three modes of type spi_ss_output_mode_t.

void SPI_HAL_SetDataFormat	(	SPI_Type *	base,
		spi_clock_polarity_t	polarity,
		spi_clock_phase_t	phase,
		spi_shift_direction_t	direction
	)

This function configures the clock polarity, clock phase, and data shift direction.

Parameters

base	Module base pointer of type SPI_Type.
polarity	Clock polarity setting of type spi_clock_polarity_t.
phase	Clock phase setting of type spi_clock_phase_t.
direction	Data shift direction (MSB or LSB) of type spi_shift_direction_t.

static uint32_t SPI_HAL_GetDataRegAddr ( SPI_Type * base )

inlinestatic

This function gets the SPI data register address as this value is needed for DMA operation.

Parameters

base	Module base pointer of type SPI_Type.

Returns: The SPI data register address.

void SPI_HAL_SetPinMode	(	SPI_Type *	base,
		spi_pin_mode_t	mode
	)

This function configures the SPI data pins to one of three modes (of type spi_pin_mode_t): Single direction mode: MOSI and MISO pins operate in normal, single direction mode. Bidirectional mode: Master: MOSI configured as input, Slave: MISO configured as input. Bidirectional mode: Master: MOSI configured as output, Slave: MISO configured as output.

Parameters

base	Module base pointer of type SPI_Type.
mode	Operational of SPI pins of type spi_pin_mode_t.

void SPI_HAL_SetIntMode	(	SPI_Type *	base,
		spi_interrupt_source_t	interrupt,
		bool	enable
	)

This function enables or disables the SPI receive buffer (or FIFO if the module supports a FIFO) full and mode fault interrupt, SPI transmit buffer (or FIFO if the module supports a FIFO) empty interrupt, and the SPI match interrupt.

Example, to set the receive and mode fault interrupt: SPI_HAL_SetIntMode(base, kSpiRxFullAndModfInt, true);

Parameters

base	Module base pointer of type SPI_Type.
interrupt	SPI interrupt source to configure of type spi_interrupt_source_t.
enable	Enable (true) or disable (false) the receive buffer full and mode fault interrupt.

static void SPI_HAL_SetReceiveAndFaultIntCmd	(	SPI_Type *	base,
		bool	enable
	)

inlinestatic

This function enables or disables the SPI receive buffer (or FIFO if the module supports a FIFO) full and mode fault interrupt.

Parameters

base	Module base pointer of type SPI_Type.
enable	Enable (true) or disable (false) the receive buffer full and mode fault interrupt.

static void SPI_HAL_SetTransmitIntCmd	(	SPI_Type *	base,
		bool	enable
	)

inlinestatic

This function enables or disables the SPI transmit buffer (or FIFO if the module supports a FIFO) empty interrupt.

Parameters

base	Module base pointer of type SPI_Type.
enable	Enable (true) or disable (false) the transmit buffer empty interrupt.

static void SPI_HAL_SetMatchIntCmd	(	SPI_Type *	base,
		bool	enable
	)

inlinestatic

This function enables or disables the SPI match interrupt.

Parameters

base	Module base pointer of type SPI_Type.
enable	Enable (true) or disable (false) the match interrupt.

static bool SPI_HAL_GetIntStatusFlag	(	SPI_Type *	base,
		spi_int_status_flag_t	flag
	)

inlinestatic

This function returns the state (set or cleared) of the SPI interrupt status flag.

Parameters

base	Module base pointer of type SPI_Type.
flag	The requested interrupt status flag of type spi_int_status_flag_t.

Returns: Current setting of the requested interrupt status flag.

static bool SPI_HAL_IsReadBuffFullPending ( SPI_Type * base )

inlinestatic

The read buffer (or FIFO if the module supports a FIFO) full flag is only cleared by reading it when it is set, then reading the data register by calling the SPI_HAL_ReadData(). This example code demonstrates how to check the flag, read data, and clear the flag.

// Check read buffer flag.
if (SPI_HAL_IsReadBuffFullPending(base))
{
    // Read the data in the buffer, which also clears the flag.
    byte = SPI_HAL_ReadData(base);
}

Parameters

base	Module base pointer of type SPI_Type.

Returns: Current setting of the read buffer full flag.

static bool SPI_HAL_IsTxBuffEmptyPending ( SPI_Type * base )

inlinestatic

To clear the transmit buffer (or FIFO if the module supports a FIFO) empty flag, read the flag when it is set. Then, write a new data value into the transmit buffer with a call to the SPI_HAL_WriteData(). The example code shows how to do this.

// Check if transmit buffer is empty.
if (SPI_HAL_IsTxBuffEmptyPending(base))
{
    // Buffer has room, so write the next data value.
    SPI_HAL_WriteData(base, byte);
}

Parameters

base	Module base pointer of type SPI_Type.

Returns: Current setting of the transmit buffer empty flag.

static bool SPI_HAL_IsModeFaultPending ( SPI_Type * base )

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.

Returns: Current setting of the mode fault flag.

void SPI_HAL_ClearModeFaultFlag ( SPI_Type * base )

Parameters

base	Module base pointer of type SPI_Type

static bool SPI_HAL_IsMatchPending ( SPI_Type * base )

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.

Returns: Current setting of the match flag.

void SPI_HAL_ClearMatchFlag ( SPI_Type * base )

Parameters

base	Module base pointer of type SPI_Type.

static uint8_t SPI_HAL_ReadData ( SPI_Type * base )

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.

Returns: The data read from the data buffer.

static void SPI_HAL_WriteData	(	SPI_Type *	base,
		uint8_t	data
	)

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.
data	The data to send.

void SPI_HAL_WriteDataBlocking	(	SPI_Type *	base,
		uint8_t	data
	)

This function writes data to the SPI data register and waits until the TX is empty to return.

Parameters

base	Module base pointer of type SPI_Type.
data	The data to send.

static void SPI_HAL_SetMatchValue	(	SPI_Type *	base,
		uint8_t	matchByte
	)

inlinestatic

Parameters

base	Module base pointer of type SPI_Type.
matchByte	The value which triggers the match interrupt.

Overview

Files

Enumerations

Configuration

Interrupts

Status

Data transfer

Match byte

Enumeration Type Documentation

Function Documentation