Overview

The MCUXpresso SDK provides a peripheral driver for the Universal Asynchronous Receiver/Transmitter (LPSCI) module of MCUXpresso SDK devices.

The LPSCI driver can be split into 2 parts: functional APIs and transactional APIs.

Functional APIs are feature/property target low level APIs. Functional APIs can be used for the LPSCI initialization/configuration/operation for optimization/customization purpose. Using the functional API requires knowledge of the LPSCI peripheral and how to organize functional APIs to meet the application requirements. All functional APIs use the peripheral base address as the first parameter. The LPSCI functional operation groups provide the functional APIs set.

The transactional APIs are transaction target high level APIs. Transactional APIs can be used to enable the peripheral quickly and also in the user's application if the code size and performance of transactional APIs can satisfy the user's requirements. If there are special requirements for the code size and performance, see the transactional API implementation and write custom code. All transactional APIs use the lpsci_handle_t as the second parameter. Initialize the handle by calling the LPSCI_TransferCreateHandle() API.

Transactional APIs support queue feature for both transmit/receive. Whenever the user calls the LPSCI_TransferSendNonBlocking() or LPSCI_TransferReceiveNonBlocking(), the transfer structure is queued into the internally maintained software queue. The driver automatically continues the transmit/receive if the queue is not empty. When a transfer is finished, the callback is called to inform the user about the completion.

The LPSCI transactional APIs support the background receive. Provide the ringbuffer address and size while calling the LPSCI_TransferCreateHandle() API. The driver automatically starts receiving the data from the receive buffer into the ringbuffer. When the user makes subsequent calls to the LPSCI_ReceiveDataIRQ(), the driver provides the received data in the ringbuffer for user buffer directly and queues the left buffer into the receive queue.

Function groups

LPSCI functional Operation

This function group implements the LPSCI functional API. Functional APIs are feature-oriented.

LPSCI transactional Operation

This function group implements the LPSCI transactional API.

LPSCI transactional Operation

This function group implements the LPSCI DMA transactional API.

Typical use case

LPSCI Operation

Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/lpsci

LPSCI Send/Receive using an interrupt method

LPSCI Receive using the ringbuffer feature

LPSCI Send/Receive using the DMA method

Data Structures
struct	lpsci_config_t
	LPSCI configure structure. More...

struct	lpsci_transfer_t
	LPSCI transfer structure. More...

Driver version
enum	_lpsci_status { kStatus_LPSCI_TxBusy = MAKE_STATUS(kStatusGroup_LPSCI, 0), kStatus_LPSCI_RxBusy = MAKE_STATUS(kStatusGroup_LPSCI, 1), kStatus_LPSCI_TxIdle = MAKE_STATUS(kStatusGroup_LPSCI, 2), kStatus_LPSCI_RxIdle = MAKE_STATUS(kStatusGroup_LPSCI, 3), kStatus_LPSCI_FlagCannotClearManually, kStatus_LPSCI_BaudrateNotSupport, kStatus_LPSCI_Error = MAKE_STATUS(kStatusGroup_LPSCI, 6), kStatus_LPSCI_RxRingBufferOverrun, kStatus_LPSCI_RxHardwareOverrun = MAKE_STATUS(kStatusGroup_LPSCI, 8), kStatus_LPSCI_NoiseError = MAKE_STATUS(kStatusGroup_LPSCI, 9), kStatus_LPSCI_FramingError = MAKE_STATUS(kStatusGroup_LPSCI, 10), kStatus_LPSCI_ParityError = MAKE_STATUS(kStatusGroup_LPSCI, 11), kStatus_LPSCI_IdleLineDetected = MAKE_STATUS(kStatusGroup_LPSCI, 12) }
	Error codes for the LPSCI driver. More...

enum	lpsci_parity_mode_t { kLPSCI_ParityDisabled = 0x0U, kLPSCI_ParityEven = 0x2U, kLPSCI_ParityOdd = 0x3U }
	LPSCI parity mode. More...

enum	lpsci_stop_bit_count_t { kLPSCI_OneStopBit = 0U, kLPSCI_TwoStopBit = 1U }
	LPSCI stop bit count. More...

enum	lpsci_idle_line_type_t { kLPSCI_IdleLineStartBit = 0U, kLPSCI_IdleLineStopBit = 1U }
	LPSCI stop bit count. More...

enum	_lpsci_interrupt_enable_t { kLPSCI_LinBreakInterruptEnable = (UART0_BDH_LBKDIE_MASK), kLPSCI_RxActiveEdgeInterruptEnable = (UART0_BDH_RXEDGIE_MASK), kLPSCI_TxDataRegEmptyInterruptEnable = (UART0_C2_TIE_MASK << 8), kLPSCI_TransmissionCompleteInterruptEnable = (UART0_C2_TCIE_MASK << 8), kLPSCI_RxDataRegFullInterruptEnable = (UART0_C2_RIE_MASK << 8), kLPSCI_IdleLineInterruptEnable = (UART0_C2_ILIE_MASK << 8), kLPSCI_RxOverrunInterruptEnable = (UART0_C3_ORIE_MASK << 16), kLPSCI_NoiseErrorInterruptEnable = (UART0_C3_NEIE_MASK << 16), kLPSCI_FramingErrorInterruptEnable = (UART0_C3_FEIE_MASK << 16), kLPSCI_ParityErrorInterruptEnable = (UART0_C3_PEIE_MASK << 16) }
	LPSCI interrupt configuration structure, default settings all disabled. More...

enum	_lpsci_status_flag_t { kLPSCI_TxDataRegEmptyFlag = (UART0_S1_TDRE_MASK), kLPSCI_TransmissionCompleteFlag, kLPSCI_RxDataRegFullFlag, kLPSCI_IdleLineFlag = (UART0_S1_IDLE_MASK), kLPSCI_RxOverrunFlag, kLPSCI_NoiseErrorFlag = (UART0_S1_NF_MASK), kLPSCI_FramingErrorFlag, kLPSCI_ParityErrorFlag = (UART0_S1_PF_MASK), kLPSCI_LinBreakFlag, kLPSCI_RxActiveEdgeFlag, kLPSCI_RxActiveFlag }
	LPSCI status flags. More...

typedef void(*	lpsci_transfer_callback_t )(UART0_Type base, lpsci_handle_t handle, status_t status, void *userData)
	LPSCI transfer callback function. More...

#define	FSL_LPSCI_DRIVER_VERSION (MAKE_VERSION(2, 0, 4))
	LPSCI driver version 2.0.4. More...

Initialization and deinitialization
status_t	LPSCI_Init (UART0_Type base, const lpsci_config_t config, uint32_t srcClock_Hz)
	Initializes an LPSCI instance with the user configuration structure and the peripheral clock. More...

void	LPSCI_Deinit (UART0_Type *base)
	Deinitializes an LPSCI instance. More...

void	LPSCI_GetDefaultConfig (lpsci_config_t *config)
	Gets the default configuration structure and saves the configuration to a user-provided pointer. More...

status_t	LPSCI_SetBaudRate (UART0_Type *base, uint32_t baudRate_Bps, uint32_t srcClock_Hz)
	Sets the LPSCI instance baudrate. More...

Status
uint32_t	LPSCI_GetStatusFlags (UART0_Type *base)
	Gets LPSCI status flags. More...

status_t	LPSCI_ClearStatusFlags (UART0_Type *base, uint32_t mask)

Interrupts
void	LPSCI_EnableInterrupts (UART0_Type *base, uint32_t mask)
	Enables an LPSCI interrupt according to a provided mask. More...

void	LPSCI_DisableInterrupts (UART0_Type *base, uint32_t mask)
	Disables the LPSCI interrupt according to a provided mask. More...

uint32_t	LPSCI_GetEnabledInterrupts (UART0_Type *base)
	Gets the enabled LPSCI interrupts. More...

DMA Control
static uint32_t	LPSCI_GetDataRegisterAddress (UART0_Type *base)
	Gets the LPSCI data register address. More...

static void	LPSCI_EnableTxDMA (UART0_Type *base, bool enable)
	Enables or disable LPSCI transmitter DMA request. More...

static void	LPSCI_EnableRxDMA (UART0_Type *base, bool enable)
	Enables or disables the LPSCI receiver DMA. More...

Bus Operations
uint32_t	LPSCI_GetInstance (UART0_Type *base)
	Get the LPSCI instance from peripheral base address. More...

static void	LPSCI_EnableTx (UART0_Type *base, bool enable)
	Enables or disables the LPSCI transmitter. More...

static void	LPSCI_EnableRx (UART0_Type *base, bool enable)
	Enables or disables the LPSCI receiver. More...

static void	LPSCI_WriteByte (UART0_Type *base, uint8_t data)
	Writes to the TX register. More...

static uint8_t	LPSCI_ReadByte (UART0_Type *base)
	Reads the RX data register. More...

void	LPSCI_WriteBlocking (UART0_Type base, const uint8_t data, size_t length)
	Writes to the TX register using a blocking method. More...

status_t	LPSCI_ReadBlocking (UART0_Type base, uint8_t data, size_t length)
	Reads the RX register using a blocking method. More...

Transactional
void	LPSCI_TransferCreateHandle (UART0_Type base, lpsci_handle_t handle, lpsci_transfer_callback_t callback, void *userData)
	Initializes the LPSCI handle. More...

void	LPSCI_TransferStartRingBuffer (UART0_Type base, lpsci_handle_t handle, uint8_t *ringBuffer, size_t ringBufferSize)
	Sets up the RX ring buffer. More...

void	LPSCI_TransferStopRingBuffer (UART0_Type base, lpsci_handle_t handle)
	Aborts the background transfer and uninstalls the ring buffer. More...

size_t	LPSCI_TransferGetRxRingBufferLength (lpsci_handle_t *handle)
	Get the length of received data in RX ring buffer. More...

status_t	LPSCI_TransferSendNonBlocking (UART0_Type base, lpsci_handle_t handle, lpsci_transfer_t *xfer)
	Transmits a buffer of data using the interrupt method. More...

void	LPSCI_TransferAbortSend (UART0_Type base, lpsci_handle_t handle)
	Aborts the interrupt-driven data transmit. More...

status_t	LPSCI_TransferGetSendCount (UART0_Type base, lpsci_handle_t handle, uint32_t *count)
	Get the number of bytes that have been written to LPSCI TX register. More...

status_t	LPSCI_TransferReceiveNonBlocking (UART0_Type base, lpsci_handle_t handle, lpsci_transfer_t xfer, size_t receivedBytes)
	Receives buffer of data using the interrupt method. More...

void	LPSCI_TransferAbortReceive (UART0_Type base, lpsci_handle_t handle)
	Aborts interrupt driven data receiving. More...

status_t	LPSCI_TransferGetReceiveCount (UART0_Type base, lpsci_handle_t handle, uint32_t *count)
	Get the number of bytes that have been received. More...

void	LPSCI_TransferHandleIRQ (UART0_Type base, lpsci_handle_t handle)
	LPSCI IRQ handle function. More...

void	LPSCI_TransferHandleErrorIRQ (UART0_Type base, lpsci_handle_t handle)
	LPSCI Error IRQ handle function. More...

Data Structure Documentation

struct lpsci_config_t

Data Fields
uint32_t	baudRate_Bps
	LPSCI baud rate.

lpsci_parity_mode_t	parityMode
	Parity mode, disabled (default), even, odd.

lpsci_stop_bit_count_t	stopBitCount
	Number of stop bits, 1 stop bit (default) or 2 stop bits.

lpsci_idle_line_type_t	idleLineType
	IDLE line type. More...

bool	enableTx
	Enable TX.

bool	enableRx
	Enable RX.

Field Documentation

lpsci_idle_line_type_t lpsci_config_t::idleLineType

struct lpsci_transfer_t

Data Fields
uint8_t *	data
	The buffer of data to be transfer. More...

size_t	dataSize
	The byte count to be transfer. More...

Field Documentation

uint8_t* lpsci_transfer_t::data

size_t lpsci_transfer_t::dataSize

Macro Definition Documentation

#define FSL_LPSCI_DRIVER_VERSION (MAKE_VERSION(2, 0, 4))

Typedef Documentation

typedef void(* lpsci_transfer_callback_t)(UART0_Type *base, lpsci_handle_t *handle, status_t status, void *userData)

Enumeration Type Documentation

enum _lpsci_status

Enumerator
kStatus_LPSCI_TxBusy	Transmitter is busy.
kStatus_LPSCI_RxBusy	Receiver is busy.
kStatus_LPSCI_TxIdle	Transmitter is idle.
kStatus_LPSCI_RxIdle	Receiver is idle.
kStatus_LPSCI_FlagCannotClearManually	Status flag can't be manually cleared.
kStatus_LPSCI_BaudrateNotSupport	Baudrate is not support in current clock source.
kStatus_LPSCI_Error	Error happens on LPSCI.
kStatus_LPSCI_RxRingBufferOverrun	LPSCI RX software ring buffer overrun.
kStatus_LPSCI_RxHardwareOverrun	LPSCI RX receiver overrun.
kStatus_LPSCI_NoiseError	LPSCI noise error.
kStatus_LPSCI_FramingError	LPSCI framing error.
kStatus_LPSCI_ParityError	LPSCI parity error.
kStatus_LPSCI_IdleLineDetected	LPSCI idle line detected.

enum lpsci_parity_mode_t

Enumerator
kLPSCI_ParityDisabled	Parity disabled.
kLPSCI_ParityEven	Parity enabled, type even, bit setting: PE\|PT = 10.
kLPSCI_ParityOdd	Parity enabled, type odd, bit setting: PE\|PT = 11.

enum lpsci_stop_bit_count_t

Enumerator
kLPSCI_OneStopBit	One stop bit.
kLPSCI_TwoStopBit	Two stop bits.

enum lpsci_idle_line_type_t

Enumerator
kLPSCI_IdleLineStartBit	IDLE line starts count after start bit.
kLPSCI_IdleLineStopBit	IDLE line starts count after stop bit.

enum _lpsci_interrupt_enable_t

This structure contains the settings for all LPSCI interrupt configurations.

Enumerator
kLPSCI_LinBreakInterruptEnable	LIN break detect interrupt.
kLPSCI_RxActiveEdgeInterruptEnable	RX Active Edge interrupt.
kLPSCI_TxDataRegEmptyInterruptEnable	Transmit data register empty interrupt.
kLPSCI_TransmissionCompleteInterruptEnable	Transmission complete interrupt.
kLPSCI_RxDataRegFullInterruptEnable	Receiver data register full interrupt.
kLPSCI_IdleLineInterruptEnable	Idle line interrupt.
kLPSCI_RxOverrunInterruptEnable	Receiver Overrun interrupt.
kLPSCI_NoiseErrorInterruptEnable	Noise error flag interrupt.
kLPSCI_FramingErrorInterruptEnable	Framing error flag interrupt.
kLPSCI_ParityErrorInterruptEnable	Parity error flag interrupt.

enum _lpsci_status_flag_t

This provides constants for the LPSCI status flags for use in the LPSCI functions.

Enumerator
kLPSCI_TxDataRegEmptyFlag	Tx data register empty flag, sets when Tx buffer is empty.
kLPSCI_TransmissionCompleteFlag	Transmission complete flag, sets when transmission activity complete.
kLPSCI_RxDataRegFullFlag	Rx data register full flag, sets when the receive data buffer is full.
kLPSCI_IdleLineFlag	Idle line detect flag, sets when idle line detected.
kLPSCI_RxOverrunFlag	Rx Overrun, sets when new data is received before data is read from receive register.
kLPSCI_NoiseErrorFlag	Rx takes 3 samples of each received bit. If any of these samples differ, noise flag sets
kLPSCI_FramingErrorFlag	Frame error flag, sets if logic 0 was detected where stop bit expected.
kLPSCI_ParityErrorFlag	If parity enabled, sets upon parity error detection.
kLPSCI_LinBreakFlag	LIN break detect interrupt flag, sets when LIN break char detected and LIN circuit enabled.
kLPSCI_RxActiveEdgeFlag	Rx pin active edge interrupt flag, sets when active edge detected.
kLPSCI_RxActiveFlag	Receiver Active Flag (RAF), sets at beginning of valid start bit.

Function Documentation

status_t LPSCI_Init	(	UART0_Type *	base,
		const lpsci_config_t *	config,
		uint32_t	srcClock_Hz
	)

This function configures the LPSCI module with user-defined settings. The user can configure the configuration structure and can also get the default configuration by calling the LPSCI_GetDefaultConfig() function. Example below shows how to use this API to configure the LPSCI.

*   lpsci_config_t lpsciConfig;
*   lpsciConfig.baudRate_Bps = 115200U;
*   lpsciConfig.parityMode = kLPSCI_ParityDisabled;
*   lpsciConfig.stopBitCount = kLPSCI_OneStopBit;
*   LPSCI_Init(UART0, &lpsciConfig, 20000000U);
*   

Parameters

base	LPSCI peripheral base address.
config	Pointer to user-defined configuration structure.
srcClock_Hz	LPSCI clock source frequency in HZ.

Return values

kStatus_LPSCI_BaudrateNotSupport	Baudrate is not support in current clock source.
kStatus_Success	LPSCI initialize succeed

void LPSCI_Deinit ( UART0_Type * base )

This function waits for TX complete, disables TX and RX, and disables the LPSCI clock.

Parameters

base	LPSCI peripheral base address.

void LPSCI_GetDefaultConfig ( lpsci_config_t * config )

This function initializes the LPSCI configure structure to default value. the default value are: lpsciConfig->baudRate_Bps = 115200U; lpsciConfig->parityMode = kLPSCI_ParityDisabled; lpsciConfig->stopBitCount = kLPSCI_OneStopBit; lpsciConfig->idleLineType = kLPSCI_IdleLineStartBit; lpsciConfig->enableTx = false; lpsciConfig->enableRx = false;

Parameters

config Pointer to configuration structure.

status_t LPSCI_SetBaudRate	(	UART0_Type *	base,
		uint32_t	baudRate_Bps,
		uint32_t	srcClock_Hz
	)

This function configures the LPSCI module baudrate. This function is used to update the LPSCI module baudrate after the LPSCI module is initialized with the LPSCI_Init.

* LPSCI_SetBaudRate(UART0, 115200U, 20000000U);

*

Parameters

base	LPSCI peripheral base address.
baudRate_Bps	LPSCI baudrate to be set.
srcClock_Hz	LPSCI clock source frequency in HZ.

Return values

kStatus_LPSCI_BaudrateNotSupport	Baudrate is not supported in the current clock source.
kStatus_Success	Set baudrate succeed

uint32_t LPSCI_GetStatusFlags ( UART0_Type * base )

This function gets all LPSCI status flags. The flags are returned as the logical OR value of the enumerators _lpsci_flags. To check a specific status, compare the return value to the enumerators in _LPSCI_flags. For example, to check whether the TX is empty:

*     if (kLPSCI_TxDataRegEmptyFlag | LPSCI_GetStatusFlags(UART0))
*     {
*         ...
*     }
* 

Parameters

base	LPSCI peripheral base address.

Returns: LPSCI status flags which are ORed by the enumerators in the _lpsci_flags.

void LPSCI_EnableInterrupts	(	UART0_Type *	base,
		uint32_t	mask
	)

This function enables the LPSCI interrupts according to a provided mask. The mask is a logical OR of enumeration members. See _lpsci_interrupt_enable. For example, to enable the TX empty interrupt and RX full interrupt:

* LPSCI_EnableInterrupts(UART0,kLPSCI_TxDataRegEmptyInterruptEnable | kLPSCI_RxDataRegFullInterruptEnable);

*

Parameters

base	LPSCI peripheral base address.
mask	The interrupts to enable. Logical OR of _lpsci_interrupt_enable.

void LPSCI_DisableInterrupts	(	UART0_Type *	base,
		uint32_t	mask
	)

This function disables the LPSCI interrupts according to a provided mask. The mask is a logical OR of enumeration members. See _lpsci_interrupt_enable. For example, to disable TX empty interrupt and RX full interrupt:

* LPSCI_DisableInterrupts(UART0,kLPSCI_TxDataRegEmptyInterruptEnable | kLPSCI_RxDataRegFullInterruptEnable);

*

Parameters

base	LPSCI peripheral base address.
mask	The interrupts to disable. Logical OR of _LPSCI_interrupt_enable.

uint32_t LPSCI_GetEnabledInterrupts ( UART0_Type * base )

This function gets the enabled LPSCI interrupts, which are returned as the logical OR value of the enumerators _lpsci_interrupt_enable. To check a specific interrupts enable status, compare the return value to the enumerators in _LPSCI_interrupt_enable. For example, to check whether TX empty interrupt is enabled:

*     uint32_t enabledInterrupts = LPSCI_GetEnabledInterrupts(UART0);
*
*     if (kLPSCI_TxDataRegEmptyInterruptEnable & enabledInterrupts)
*     {
*         ...
*     }
* 

Parameters

base	LPSCI peripheral base address.

Returns: LPSCI interrupt flags which are logical OR of the enumerators in _LPSCI_interrupt_enable.

static uint32_t LPSCI_GetDataRegisterAddress ( UART0_Type * base )

inlinestatic

This function returns the LPSCI data register address, which is mainly used by DMA/eDMA case.

Parameters

base	LPSCI peripheral base address.

Returns: LPSCI data register address which are used both by transmitter and receiver.

static void LPSCI_EnableTxDMA	(	UART0_Type *	base,
		bool	enable
	)

inlinestatic

This function enables or disables the transmit data register empty flag, S1[TDRE], to generate DMA requests.

Parameters

base	LPSCI peripheral base address.
enable	True to enable, false to disable.

static void LPSCI_EnableRxDMA	(	UART0_Type *	base,
		bool	enable
	)

inlinestatic

This function enables or disables the receiver data register full flag, S1[RDRF], to generate DMA requests.

Parameters

base	LPSCI peripheral base address.
enable	True to enable, false to disable.

uint32_t LPSCI_GetInstance ( UART0_Type * base )

Parameters

base	LPSCI peripheral base address.

Returns: LPSCI instance.

static void LPSCI_EnableTx	(	UART0_Type *	base,
		bool	enable
	)

inlinestatic

This function enables or disables the LPSCI transmitter.

Parameters

base	LPSCI peripheral base address.
enable	True to enable, false to disable.

static void LPSCI_EnableRx	(	UART0_Type *	base,
		bool	enable
	)

inlinestatic

This function enables or disables the LPSCI receiver.

Parameters

base	LPSCI peripheral base address.
enable	True to enable, false to disable.

static void LPSCI_WriteByte	(	UART0_Type *	base,
		uint8_t	data
	)

inlinestatic

This function writes data to the TX register directly. The upper layer must ensure that the TX register is empty before calling this function.

Parameters

base	LPSCI peripheral base address.
data	Data write to TX register.

static uint8_t LPSCI_ReadByte ( UART0_Type * base )

inlinestatic

This function reads data from the RX register directly. The upper layer must ensure that the RX register is full before calling this function.

Parameters

base	LPSCI peripheral base address.

Returns: Data read from RX data register.

void LPSCI_WriteBlocking	(	UART0_Type *	base,
		const uint8_t *	data,
		size_t	length
	)

This function polls the TX register, waits for the TX register empty, and writes data to the TX buffer.

Note: This function does not check whether all the data has been sent out to bus, so before disable TX, check kLPSCI_TransmissionCompleteFlag to ensure the TX is finished.

Parameters

base	LPSCI peripheral base address.
data	Start address of the data to write.
length	Size of the data to write.

status_t LPSCI_ReadBlocking	(	UART0_Type *	base,
		uint8_t *	data,
		size_t	length
	)

This function polls the RX register, waits for the RX register to be full, and reads data from the RX register.

Parameters

base	LPSCI peripheral base address.
data	Start address of the buffer to store the received data.
length	Size of the buffer.

Return values

kStatus_LPSCI_RxHardwareOverrun	Receiver overrun happened while receiving data.
kStatus_LPSCI_NoiseError	Noise error happened while receiving data.
kStatus_LPSCI_FramingError	Framing error happened while receiving data.
kStatus_LPSCI_ParityError	Parity error happened while receiving data.
kStatus_Success	Successfully received all data.

void LPSCI_TransferCreateHandle	(	UART0_Type *	base,
		lpsci_handle_t *	handle,
		lpsci_transfer_callback_t	callback,
		void *	userData
	)

This function initializes the LPSCI handle, which can be used for other LPSCI transactional APIs. Usually, for a specified LPSCI instance, call this API once to get the initialized handle.

LPSCI driver supports the "background" receiving, which means that the user can set up an RX ring buffer optionally. Data received are stored into the ring buffer even when the user doesn't call the LPSCI_TransferReceiveNonBlocking() API. If there is already data received in the ring buffer, get the received data from the ring buffer directly. The ring buffer is disabled if pass NULL as ringBuffer.

Parameters

handle	LPSCI handle pointer.
base	LPSCI peripheral base address.
ringBuffer	Start address of ring buffer for background receiving. Pass NULL to disable the ring buffer.
ringBufferSize	size of the ring buffer.

void LPSCI_TransferStartRingBuffer	(	UART0_Type *	base,
		lpsci_handle_t *	handle,
		uint8_t *	ringBuffer,
		size_t	ringBufferSize
	)

This function sets up the RX ring buffer to a specific LPSCI handle.

When the RX ring buffer is used, data received is stored into the ring buffer even when the user doesn't call the LPSCI_TransferReceiveNonBlocking() API. If there is already data received in the ring buffer, the user can get the received data from the ring buffer directly.

Note: When using the RX ring buffer, one byte is reserved for internal use. In other words, if ringBufferSize is 32, only 31 bytes are used for saving data.

Parameters

base	LPSCI peripheral base address.
handle	LPSCI handle pointer.
ringBuffer	Start address of ring buffer for background receiving. Pass NULL to disable the ring buffer.
ringBufferSize	size of the ring buffer.

void LPSCI_TransferStopRingBuffer	(	UART0_Type *	base,
		lpsci_handle_t *	handle
	)

This function aborts the background transfer and uninstalls the ringbuffer.

Parameters

base	LPSCI peripheral base address.
handle	LPSCI handle pointer.

size_t LPSCI_TransferGetRxRingBufferLength ( lpsci_handle_t * handle )

handle LPSCI handle pointer.

Returns: Length of received data in RX ring buffer.

status_t LPSCI_TransferSendNonBlocking	(	UART0_Type *	base,
		lpsci_handle_t *	handle,
		lpsci_transfer_t *	xfer
	)

This function sends data using the interrupt method. This is a non-blocking function, which returns directly without waiting for all data to be written to the TX register. When all data is written to the TX register in ISR, LPSCI driver calls the callback function and passes the kStatus_LPSCI_TxIdle as status parameter.

Note: The kStatus_LPSCI_TxIdle is passed to the upper layer when all data is written to the TX register. However, it does not ensure that all data is sent out. Before disabling the TX, check the kLPSCI_TransmissionCompleteFlag to ensure that the TX is complete.

Parameters

handle	LPSCI handle pointer.
xfer	LPSCI transfer structure, refer to #LPSCI_transfer_t.

Return values

kStatus_Success	Successfully start the data transmission.
kStatus_LPSCI_TxBusy	Previous transmission still not finished, data not all written to the TX register.
kStatus_InvalidArgument	Invalid argument.

void LPSCI_TransferAbortSend	(	UART0_Type *	base,
		lpsci_handle_t *	handle
	)

This function aborts the interrupt driven data send.

Parameters

handle LPSCI handle pointer.

status_t LPSCI_TransferGetSendCount	(	UART0_Type *	base,
		lpsci_handle_t *	handle,
		uint32_t *	count
	)

This function gets the number of bytes that have been written to LPSCI TX register by interrupt method.

Parameters

base	LPSCI peripheral base address.
handle	LPSCI handle pointer.
count	Send bytes count.

Return values

kStatus_NoTransferInProgress	No send in progress.
kStatus_InvalidArgument	Parameter is invalid.
kStatus_Success	Get successfully through the parameter `count`;

status_t LPSCI_TransferReceiveNonBlocking	(	UART0_Type *	base,
		lpsci_handle_t *	handle,
		lpsci_transfer_t *	xfer,
		size_t *	receivedBytes
	)

This function receives data using the interrupt method. This is a non-blocking function which returns without waiting for all data to be received. If the RX ring buffer is used and not empty, the data in ring buffer is copied and the parameter receivedBytes shows how many bytes are copied from the ring buffer. After copying, if the data in ring buffer is not enough to read, the receive request is saved by the LPSCI driver. When new data arrives, the receive request is serviced first. When all data is received, the LPSCI driver notifies the upper layer through a callback function and passes the status parameter kStatus_LPSCI_RxIdle. For example, the upper layer needs 10 bytes but there are only 5 bytes in the ring buffer. The 5 bytes are copied to the xfer->data and the function returns with the parameter receivedBytes set to 5. For the remaining 5 bytes, newly arrived data is saved from the xfer->data[5]. When 5 bytes are received, the LPSCI driver notifies the upper layer. If the RX ring buffer is not enabled, this function enables the RX and RX interrupt to receive data to the xfer->data. When all data is received, the upper layer is notified.

Parameters

handle	LPSCI handle pointer.
xfer	lpsci transfer structure. See lpsci_transfer_t.
receivedBytes	Bytes received from the ring buffer directly.

Return values

kStatus_Success	Successfully queue the transfer into transmit queue.
kStatus_LPSCI_RxBusy	Previous receive request is not finished.
kStatus_InvalidArgument	Invalid argument.

void LPSCI_TransferAbortReceive	(	UART0_Type *	base,
		lpsci_handle_t *	handle
	)

This function aborts interrupt driven data receiving.

Parameters

handle LPSCI handle pointer.

status_t LPSCI_TransferGetReceiveCount	(	UART0_Type *	base,
		lpsci_handle_t *	handle,
		uint32_t *	count
	)

This function gets the number of bytes that have been received.

Parameters

base	LPSCI peripheral base address.
handle	LPSCI handle pointer.
count	Receive bytes count.

Return values

kStatus_NoTransferInProgress	No receive in progress.
kStatus_InvalidArgument	Parameter is invalid.
kStatus_Success	Get successfully through the parameter `count`;

void LPSCI_TransferHandleIRQ	(	UART0_Type *	base,
		lpsci_handle_t *	handle
	)

This function handles the LPSCI transmit and receive IRQ request.

Parameters

handle LPSCI handle pointer.

void LPSCI_TransferHandleErrorIRQ	(	UART0_Type *	base,
		lpsci_handle_t *	handle
	)

This function handle the LPSCI error IRQ request.

Parameters

handle LPSCI handle pointer.

Overview

Function groups

LPSCI functional Operation

LPSCI transactional Operation

LPSCI transactional Operation

Typical use case

LPSCI Operation

LPSCI Send/Receive using an interrupt method

LPSCI Receive using the ringbuffer feature

LPSCI Send/Receive using the DMA method

Data Structures

Driver version

Initialization and deinitialization

Status

Interrupts

DMA Control

Bus Operations

Transactional

Data Structure Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Macro Definition Documentation

Typedef Documentation

Enumeration Type Documentation

Function Documentation