KPP: KeyPad Port Driver

Overview

The MCUXpresso SDK provides a peripheral driver for the KeyPad Port block of MCUXpresso SDK devices.

The KPP Initialize is to initialize for common configure: gate the KPP clock, configure columns, and rows features. The KPP Deinitialize is to ungate the clock.

The KPP provide the function to enable/disable interrupts. The KPP provide key press scanning function KPP_keyPressScanning. This API should be called by the Interrupt handler in application. KPP still provides functions to get and clear status flags.

Typical use case

Data Structures
struct	kpp_config_t
	Lists of KPP status. More...

Enumerations
enum	kpp_interrupt_enable_t {   kKPP_keyDepressInterrupt = KPP_KPSR_KDIE_MASK,   kKPP_keyReleaseInterrupt = KPP_KPSR_KRIE_MASK }
	List of interrupts supported by the peripheral. More...
enum	kpp_sync_operation_t {   kKPP_ClearKeyDepressSyncChain = KPP_KPSR_KDSC_MASK,   kKPP_SetKeyReleasesSyncChain = KPP_KPSR_KRSS_MASK }
	Lists of KPP synchronize chain operation. More...

Driver version
#define	FSL_KPP_DRIVER_VERSION   (MAKE_VERSION(2, 0, 0))
	KPP driver version 2.0.0. More...

Initialization and De-initialization
void	KPP_Init (KPP_Type *base, kpp_config_t *configure)
	KPP initialize. More...
void	KPP_Deinit (KPP_Type *base)
	Deinitializes the KPP module and gates the clock. More...

KPP Basic Operation
static void	KPP_EnableInterrupts (KPP_Type *base, uint16_t mask)
	Enable the interrupt. More...
static void	KPP_DisableInterrupts (KPP_Type *base, uint16_t mask)
	Disable the interrupt. More...
static uint16_t	KPP_GetStatusFlag (KPP_Type *base)
	Gets the KPP interrupt event status. More...
static void	KPP_ClearStatusFlag (KPP_Type *base, uint16_t mask)
	Clears KPP status flag. More...
static void	KPP_SetSynchronizeChain (KPP_Type *base, uint16_t mask)
	Set KPP synchronization chain. More...
void	KPP_keyPressScanning (KPP_Type *base, uint8_t *data, uint32_t clockSrc_Hz)
	Keypad press scanning. More...

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Data Structure Documentation

struct kpp_config_t

Data Fields
uint8_t	activeRow
	The row number: bit 7 ~ 0 represents the row 7 ~ 0. More...
uint8_t	activeColumn
	The column number: bit 7 ~ 0 represents the column 7 ~ 0. More...
uint16_t	interrupt
	KPP interrupt source. More...

Field Documentation

uint8_t kpp_config_t::activeRow

uint8_t kpp_config_t::activeColumn

uint16_t kpp_config_t::interrupt

A logical OR of "kpp_interrupt_enable_t".

Macro Definition Documentation

#define FSL_KPP_DRIVER_VERSION   (MAKE_VERSION(2, 0, 0))

Enumeration Type Documentation

enum kpp_interrupt_enable_t

This enumeration uses one-bot encoding to allow a logical OR of multiple members. Members usually map to interrupt enable bits in one or more peripheral registers.

Enumerator
kKPP_keyDepressInterrupt	Keypad depress interrupt source.
kKPP_keyReleaseInterrupt	Keypad release interrupt source.

enum kpp_sync_operation_t

Enumerator
kKPP_ClearKeyDepressSyncChain	Keypad depress interrupt status.
kKPP_SetKeyReleasesSyncChain	Keypad release interrupt status.

Function Documentation

void KPP_Init	(	KPP_Type *	base,
		kpp_config_t *	configure
	)

This function ungates the KPP clock and initializes KPP. This function must be called before calling any other KPP driver functions.

Parameters

base	KPP peripheral base address.
configure	The KPP configuration structure pointer.

void KPP_Deinit

(

KPP_Type *

base

)

This function gates the KPP clock. As a result, the KPP module doesn't work after calling this function.

Parameters

base	KPP peripheral base address.

static void KPP_EnableInterrupts ( KPP_Type *  base, uint16_t  mask  )

inlinestatic

Parameters

base	KPP peripheral base address.
mask	KPP interrupts to enable. This is a logical OR of the enumeration :: kpp_interrupt_enable_t.

static void KPP_DisableInterrupts ( KPP_Type *  base, uint16_t  mask  )

inlinestatic

Parameters

base	KPP peripheral base address.
mask	KPP interrupts to disable. This is a logical OR of the enumeration :: kpp_interrupt_enable_t.

static uint16_t KPP_GetStatusFlag ( KPP_Type *  base )

inlinestatic

Parameters

base	KPP peripheral base address.

Returns

The status of the KPP. Application can use the enum type in the "kpp_interrupt_enable_t" to get the right status of the related event.

static void KPP_ClearStatusFlag ( KPP_Type *  base, uint16_t  mask  )

inlinestatic

Parameters

base	KPP peripheral base address.
mask	KPP mask to be cleared. This is a logical OR of the enumeration :: kpp_interrupt_enable_t.

static void KPP_SetSynchronizeChain ( KPP_Type *  base, uint16_t  mask  )

inlinestatic

Parameters

base	KPP peripheral base address.
mask	KPP mask to be cleared. This is a logical OR of the enumeration :: kpp_sync_operation_t.

void KPP_keyPressScanning	(	KPP_Type *	base,
		uint8_t *	data,
		uint32_t	clockSrc_Hz
	)

This function will scanning all columns and rows. so all scanning data will be stored in the data pointer.

Parameters

base	KPP peripheral base address.
data	KPP key press scanning data. The data buffer should be prepared with length at least equal to KPP_KEYPAD_COLUMNNUM_MAX * KPP_KEYPAD_ROWNUM_MAX. the data pointer is recommended to be a array like uint8_t data[KPP_KEYPAD_COLUMNNUM_MAX]. for example the data[2] = 4, that means in column 1 row 2 has a key press event.