Overview

The MCUXpresso SDK provides a peripheral driver for the Analog Comparator (CMP) module of MCUXpresso SDK devices.

Function groups

The driver provides a set of functions to set two input sources of the on-chip comparator and compare the voltage of them.

Initialization and deinitialization

The function CMP_Init() initializes the CMP with specified configurations. The function CMP_GetDefaultConfig() gets the default configurations.

The function CMP_Deinit() disables the module clock.

Compare

The function CMP_SetInputChannels() configures the P-side and N-side input sources.

The function CMP_SetVREF() sets the reference voltage which can be dedicated to input 0 of both P and N sides.

The function CMP_GetOutput() gets the compare result of the two sides.

Interrupt

Provides functions to enable/disable/clear CMP interrupts.

The function CMP_EnableFilteredInterruptSource() allows users to select which analog comparator output (filtered or un-filtered) is used for interrupt detection.

Status

Provides functions to get the CMP status.

Typical use case

Polling Configuration

Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/cmp_1

Interrupt Configuration

Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/cmp_1

Data Structures
struct	cmp_config_t
	CMP configuration structure. More...

Enumerations
enum	_cmp_input_mux { kCMP_InputVREF = 0U, kCMP_Input1 = 1U, kCMP_Input2 = 2U, kCMP_Input3 = 3U, kCMP_Input4 = 4U, kCMP_Input5 = 5U }
	CMP input mux for positive and negative sides. More...

enum	_cmp_interrupt_type { kCMP_EdgeDisable = 0U, kCMP_EdgeRising = 2U, kCMP_EdgeFalling = 4U, kCMP_EdgeRisingFalling = 6U, kCMP_LevelDisable = 1U, kCMP_LevelHigh = 3U, kCMP_LevelLow = 5U }
	CMP interrupt type. More...

enum	cmp_vref_source_t { KCMP_VREFSourceVDDA = 1U, KCMP_VREFSourceInternalVREF = 0U }
	CMP Voltage Reference source. More...

enum	cmp_filtercgf_samplemode_t { kCMP_FilterSampleMode0 = 0U, kCMP_FilterSampleMode1 = 1U, kCMP_FilterSampleMode2 = 2U, kCMP_FilterSampleMode3 = 3U }
	CMP Filter sample mode. More...

enum	cmp_filtercgf_clkdiv_t { kCMP_FilterClockDivide1 = 0U, kCMP_FilterClockDivide2 = 1U, kCMP_FilterClockDivide4 = 2U, kCMP_FilterClockDivide8 = 3U, kCMP_FilterClockDivide16 = 4U, kCMP_FilterClockDivide32 = 5U, kCMP_FilterClockDivide64 = 6U }
	CMP Filter clock divider. More...

Driver version
#define	FSL_CMP_DRIVER_VERSION (MAKE_VERSION(2U, 2U, 1U))
	Driver version 2.2.1. More...

Initialization and deinitialization
void	CMP_Init (const cmp_config_t *config)
	CMP initialization. More...

void	CMP_Deinit (void)
	CMP deinitialization. More...

void	CMP_GetDefaultConfig (cmp_config_t *config)
	Initializes the CMP user configuration structure. More...

Compare Interface
static void	CMP_SetInputChannels (uint8_t positiveChannel, uint8_t negativeChannel)

void	CMP_SetVREF (const cmp_vref_config_t *config)
	Configures the VREFINPUT. More...

static bool	CMP_GetOutput (void)
	Get CMP compare output. More...

Interrupt Interface
static void	CMP_EnableInterrupt (uint32_t type)
	CMP enable interrupt. More...

static void	CMP_DisableInterrupt (void)
	CMP disable interrupt.

static void	CMP_ClearInterrupt (void)
	CMP clear interrupt.

static void	CMP_EnableFilteredInterruptSource (bool enable)
	Select which Analog comparator output (filtered or un-filtered) is used for interrupt detection. More...

Status Interface
static bool	CMP_GetPreviousInterruptStatus (void)
	Get CMP interrupt status before interupt enable. More...

static bool	CMP_GetInterruptStatus (void)
	Get CMP interrupt status after interupt enable. More...

Filter Interface
static void	CMP_FilterSampleConfig (cmp_filtercgf_samplemode_t filterSampleMode, cmp_filtercgf_clkdiv_t filterClockDivider)
	CMP Filter Sample Config. More...

Data Structure Documentation

struct cmp_config_t

Data Fields
bool	enableHysteresis
	Enable hysteresis. More...

bool	enableLowPower
	Enable low power mode. More...

Field Documentation

bool cmp_config_t::enableHysteresis

bool cmp_config_t::enableLowPower

Macro Definition Documentation

#define FSL_CMP_DRIVER_VERSION (MAKE_VERSION(2U, 2U, 1U))

Enumeration Type Documentation

enum _cmp_input_mux

Enumerator
kCMP_InputVREF	Cmp input from VREF.
kCMP_Input1	Cmp input source 1.
kCMP_Input2	Cmp input source 2.
kCMP_Input3	Cmp input source 3.
kCMP_Input4	Cmp input source 4.
kCMP_Input5	Cmp input source 5.

enum _cmp_interrupt_type

Enumerator
kCMP_EdgeDisable	Disable edge interupt.
kCMP_EdgeRising	Interrupt on falling edge.
kCMP_EdgeFalling	Interrupt on rising edge.
kCMP_EdgeRisingFalling	Interrupt on both rising and falling edges.
kCMP_LevelDisable	Disable level interupt.
kCMP_LevelHigh	Interrupt on high level.
kCMP_LevelLow	Interrupt on low level.

enum cmp_vref_source_t

Enumerator
KCMP_VREFSourceVDDA	Select VDDA as VREF.
KCMP_VREFSourceInternalVREF	Select internal VREF as VREF.

enum cmp_filtercgf_samplemode_t

Enumerator
kCMP_FilterSampleMode0	Bypass mode. Filtering is disabled.
kCMP_FilterSampleMode1	Filter 1 clock period.
kCMP_FilterSampleMode2	Filter 2 clock period.
kCMP_FilterSampleMode3	Filter 3 clock period.

enum cmp_filtercgf_clkdiv_t

Enumerator
kCMP_FilterClockDivide1	Filter clock period duration equals 1 analog comparator clock period.
kCMP_FilterClockDivide2	Filter clock period duration equals 2 analog comparator clock period.
kCMP_FilterClockDivide4	Filter clock period duration equals 4 analog comparator clock period.
kCMP_FilterClockDivide8	Filter clock period duration equals 8 analog comparator clock period.
kCMP_FilterClockDivide16	Filter clock period duration equals 16 analog comparator clock period.
kCMP_FilterClockDivide32	Filter clock period duration equals 32 analog comparator clock period.
kCMP_FilterClockDivide64	Filter clock period duration equals 64 analog comparator clock period.

Function Documentation

void CMP_Init ( const cmp_config_t * config )

This function enables the CMP module and do necessary settings.

Parameters

config Pointer to the configuration structure.

void CMP_Deinit ( void )

This function gates the clock for CMP module.

void CMP_GetDefaultConfig ( cmp_config_t * config )

This function initializes the user configuration structure to these default values.

*   config->enableHysteresis    = true;
*   config->enableLowPower      = true;
*   config->filterClockDivider  = kCMP_FilterClockDivide1;
*   config->filterSampleMode    = kCMP_FilterSampleMode0;
* 

Parameters

config Pointer to the configuration structure.

void CMP_SetVREF ( const cmp_vref_config_t * config )

Parameters

config Pointer to the configuration structure.

static bool CMP_GetOutput ( void )

inlinestatic

Returns: The output result. true: voltage on positive side is greater than negative side. false: voltage on positive side is lower than negative side.

static void CMP_EnableInterrupt ( uint32_t type )

inlinestatic

Parameters

type	CMP interrupt type. See "_cmp_interrupt_type".

static void CMP_EnableFilteredInterruptSource ( bool enable )

inlinestatic

Parameters

enable false: Select Analog Comparator raw output (unfiltered) as input for interrupt detection. true: Select Analog Comparator filtered output as input for interrupt detection.

Note: : When CMP is configured as the wakeup source in power down mode, this function must use the raw output as the interupt source, that is, call this function and set parameter enable to false.

static bool CMP_GetPreviousInterruptStatus ( void )

inlinestatic

Returns: Interrupt status. true: interrupt pending, false: no interrupt pending.

static bool CMP_GetInterruptStatus ( void )

inlinestatic

Returns: Interrupt status. true: interrupt pending, false: no interrupt pending.

static void CMP_FilterSampleConfig	(	cmp_filtercgf_samplemode_t	filterSampleMode,
		cmp_filtercgf_clkdiv_t	filterClockDivider
	)

inlinestatic

This function allows the users to configure the sampling mode and clock divider of the CMP Filter.

Parameters

filterSampleMode	CMP Select filter sample mode
filterClockDivider	CMP Set fileter clock divider

Overview

Function groups

Initialization and deinitialization

Compare

Interrupt

Status

Typical use case

Polling Configuration

Interrupt Configuration

Data Structures

Enumerations

Driver version

Initialization and deinitialization

Compare Interface

Interrupt Interface

Status Interface

Filter Interface

Data Structure Documentation

Data Fields

Field Documentation

Macro Definition Documentation

Enumeration Type Documentation

Function Documentation