FlexIO eDMA MCU Interface LCD Driver

SDK provide eDMA transactional APIs to transfer data using eDMA, the eDMA method is similar with interrupt transactional method. More...

Overview

Note

eDMA transactional functions use multiple beats method for better performance, in contrast, the blocking functions and interupt functions use single beat method. The function FLEXIO_MCULCD_ReadData, FLEXIO_MCULCD_WriteData, FLEXIO_MCULCD_GetStatusFlags, and FLEXIO_MCULCD_ClearStatusFlags are only used for single beat case, so don't use these functions to work together with eDMA functions.

FlexIO eDMA MCU Interface LCD Driver

FLEXIO LCD send/receive using a DMA method

flexio_MCULCD_edma_handle_t handle;
volatile bool completeFlag = false;
edma_handle_t rxEdmaHandle;
edma_handle_t txEdmaHandle;

void flexioLcdCallback(FLEXIO_MCULCD_Type *base, flexio_MCULCD_edma_handle_t *handle, status_t status, void *userData)
{
    if (kStatus_FLEXIO_MCULCD_Idle == status)
    {
        completeFlag = true;
    }
}

void main(void)
{
    // Create the edma Handle.
    EDMA_CreateHandle(&rxEdmaHandle, DMA0, channel);
    EDMA_CreateHandle(&txEdmaHandle, DMA0, channel);

    // Configure the DMAMUX.
    // ...
    // rxEdmaHandle should use the last FlexIO RX shifters as DMA requst source.
    // txEdmaHandle should use the first FlexIO TX shifters as DMA requst source.

    // Init the FlexIO LCD driver.
    FLEXIO_MCULCD_Init(...);

    // Create the transactional handle.
    FLEXIO_MCULCD_TransferCreateHandleEDMA(&flexioLcdDev, &handle, flexioLcdCallback, NULL, &txEdmaHandle, &rxEdmaHandle);

    xfer.command = command2;
    xfer.mode = kFLEXIO_MCULCD_WriteArray;
    xfer.dataAddrOrSameValue = (uint32_t)dataToSend;
    xfer.dataCount = sizeof(dataToSend);
    completeFlag = false;
    FLEXIO_MCULCD_TransferEDMA(&flexioLcdDev, &handle, &xfer);

    while (!completeFlag)
    {
    }

    xfer.command = command2;
    xfer.mode = kFLEXIO_MCULCD_WriteSameValue;
    xfer.dataAddrOrSameValue = value;
    xfer.dataCount = 1000;
    completeFlag = false;
    FLEXIO_MCULCD_TransferEDMA(&flexioLcdDev, &handle, &xfer);

    while (!completeFlag)
    {
    }

    xfer.command = command3;
    xfer.mode = kFLEXIO_MCULCD_ReadArray;
    xfer.dataAddrOrSameValue = (uint32_t)dataToReceive;
    xfer.dataCount = sizeof(dataToReceive);
    completeFlag = false;
    FLEXIO_MCULCD_TransferEDMA(&flexioLcdDev, &handle, &xfer);

    while (!completeFlag)
    {
    }
}

Data Structures
struct	flexio_mculcd_edma_handle_t
	FlexIO MCULCD eDMA transfer handle, users should not touch the content of the handle. More...

Macros
#define	FSL_FLEXIO_MCULCD_EDMA_DRIVER_VERSION   (MAKE_VERSION(2, 0, 4))
	FlexIO MCULCD EDMA driver version. More...

Typedefs
typedef void(*	flexio_mculcd_edma_transfer_callback_t )(FLEXIO_MCULCD_Type *base, flexio_mculcd_edma_handle_t *handle, status_t status, void *userData)
	FlexIO MCULCD master callback for transfer complete. More...

eDMA Transactional
status_t	FLEXIO_MCULCD_TransferCreateHandleEDMA (FLEXIO_MCULCD_Type *base, flexio_mculcd_edma_handle_t *handle, flexio_mculcd_edma_transfer_callback_t callback, void *userData, edma_handle_t *txDmaHandle, edma_handle_t *rxDmaHandle)
	Initializes the FLEXO MCULCD master eDMA handle. More...
status_t	FLEXIO_MCULCD_TransferEDMA (FLEXIO_MCULCD_Type *base, flexio_mculcd_edma_handle_t *handle, flexio_mculcd_transfer_t *xfer)
	Performs a non-blocking FlexIO MCULCD transfer using eDMA. More...
void	FLEXIO_MCULCD_TransferAbortEDMA (FLEXIO_MCULCD_Type *base, flexio_mculcd_edma_handle_t *handle)
	Aborts a FlexIO MCULCD transfer using eDMA. More...
status_t	FLEXIO_MCULCD_TransferGetCountEDMA (FLEXIO_MCULCD_Type *base, flexio_mculcd_edma_handle_t *handle, size_t *count)
	Gets the remaining bytes for FlexIO MCULCD eDMA transfer. More...

---

Data Structure Documentation

struct _flexio_mculcd_edma_handle

typedef for flexio_mculcd_edma_handle_t in advance.

Data Fields
FLEXIO_MCULCD_Type *	base
	Pointer to the FLEXIO_MCULCD_Type. More...
uint8_t	txShifterNum
	Number of shifters used for TX. More...
uint8_t	rxShifterNum
	Number of shifters used for RX. More...
uint32_t	minorLoopBytes
	eDMA transfer minor loop bytes. More...
edma_modulo_t	txEdmaModulo
	Modulo value for the FlexIO shifter buffer access. More...
edma_modulo_t	rxEdmaModulo
	Modulo value for the FlexIO shifter buffer access. More...
uint32_t	dataAddrOrSameValue
	When sending the same value for many times, this is the value to send. More...
size_t	dataCount
	Total count to be transferred. More...
volatile size_t	remainingCount
	Remaining count still not transfered. More...
volatile uint32_t	state
	FlexIO MCULCD driver internal state. More...
edma_handle_t *	txDmaHandle
	DMA handle for MCULCD TX.
edma_handle_t *	rxDmaHandle
	DMA handle for MCULCD RX.
flexio_mculcd_edma_transfer_callback_t	completionCallback
	Callback for MCULCD DMA transfer.
void *	userData
	User Data for MCULCD DMA callback.

Field Documentation

FLEXIO_MCULCD_Type* flexio_mculcd_edma_handle_t::base

uint8_t flexio_mculcd_edma_handle_t::txShifterNum

uint8_t flexio_mculcd_edma_handle_t::rxShifterNum

uint32_t flexio_mculcd_edma_handle_t::minorLoopBytes

edma_modulo_t flexio_mculcd_edma_handle_t::txEdmaModulo

edma_modulo_t flexio_mculcd_edma_handle_t::rxEdmaModulo

uint32_t flexio_mculcd_edma_handle_t::dataAddrOrSameValue

When writing or reading array, this is the address of the data array.

size_t flexio_mculcd_edma_handle_t::dataCount

volatile size_t flexio_mculcd_edma_handle_t::remainingCount

volatile uint32_t flexio_mculcd_edma_handle_t::state

Macro Definition Documentation

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

Typedef Documentation

typedef void(* flexio_mculcd_edma_transfer_callback_t)(FLEXIO_MCULCD_Type *base, flexio_mculcd_edma_handle_t *handle, status_t status, void *userData)

When transfer finished, the callback function is called and returns the status as kStatus_FLEXIO_MCULCD_Idle.

Function Documentation

status_t FLEXIO_MCULCD_TransferCreateHandleEDMA	(	FLEXIO_MCULCD_Type *	base,
		flexio_mculcd_edma_handle_t *	handle,
		flexio_mculcd_edma_transfer_callback_t	callback,
		void *	userData,
		edma_handle_t *	txDmaHandle,
		edma_handle_t *	rxDmaHandle
	)

This function initializes the FLEXO MCULCD master eDMA handle which can be used for other FLEXO MCULCD transactional APIs. For a specified FLEXO MCULCD instance, call this API once to get the initialized handle.

Parameters

base	Pointer to FLEXIO_MCULCD_Type structure.
handle	Pointer to flexio_mculcd_edma_handle_t structure to store the transfer state.
callback	MCULCD transfer complete callback, NULL means no callback.
userData	callback function parameter.
txDmaHandle	User requested eDMA handle for FlexIO MCULCD eDMA TX, the DMA request source of this handle should be the first of TX shifters.
rxDmaHandle	User requested eDMA handle for FlexIO MCULCD eDMA RX, the DMA request source of this handle should be the last of RX shifters.

Return values

kStatus_Success

Successfully create the handle.

status_t FLEXIO_MCULCD_TransferEDMA	(	FLEXIO_MCULCD_Type *	base,
		flexio_mculcd_edma_handle_t *	handle,
		flexio_mculcd_transfer_t *	xfer
	)

This function returns immediately after transfer initiates. To check whether the transfer is completed, user could:

1. Use the transfer completed callback;
2. Polling function FLEXIO_MCULCD_GetTransferCountEDMA

Parameters

base	pointer to FLEXIO_MCULCD_Type structure.
handle	pointer to flexio_mculcd_edma_handle_t structure to store the transfer state.
xfer	Pointer to FlexIO MCULCD transfer structure.

Return values

kStatus_Success	Successfully start a transfer.
kStatus_InvalidArgument	Input argument is invalid.
kStatus_FLEXIO_MCULCD_Busy	FlexIO MCULCD is not idle, it is running another transfer.

void FLEXIO_MCULCD_TransferAbortEDMA	(	FLEXIO_MCULCD_Type *	base,
		flexio_mculcd_edma_handle_t *	handle
	)

Parameters

base	pointer to FLEXIO_MCULCD_Type structure.
handle	FlexIO MCULCD eDMA handle pointer.

status_t FLEXIO_MCULCD_TransferGetCountEDMA	(	FLEXIO_MCULCD_Type *	base,
		flexio_mculcd_edma_handle_t *	handle,
		size_t *	count
	)

Parameters

base	pointer to FLEXIO_MCULCD_Type structure.
handle	FlexIO MCULCD eDMA handle pointer.
count	Number of count transferred so far by the eDMA transaction.

Return values

kStatus_Success	Get the transferred count Successfully.
kStatus_NoTransferInProgress	No transfer in process.