Overview

The MCUXpresso SDK provides a peripheral driver for the Low Power Analog Comparator (LPCMP) module of Kinetis devices.

The LPCMP driver is a basic comparator with advanced features. The APIs for the basic comparator enable the LPCMP to compare the two voltages of the two input channels and create the output of the comparator result. The APIs for advanced features can be used as the plug-in functions based on the basic comparator. They can process the comparator's output with hardware support.

Typical use case

Polling Configuration

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

Interrupt Configuration

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

Initialization and configuration

Functions in this group are used to initialize and configure LPCMP module, LPCMP internal DAC, channel and filter block, etc.

Window mode

Functions in this group are used to enable/disable window and configure window control, etc.

RoundRobin mode

Functions in this group are used to configure roundrobin mode, set internal timer rate and preset value, etc.

Data Structures
struct	_lpcmp_filter_config
	Configure the filter. More...

struct	_lpcmp_dac_config
	configure the internal DAC. More...

struct	_lpcmp_config
	Configures the comparator. More...

Typedefs
typedef enum _lpcmp_hysteresis_mode	lpcmp_hysteresis_mode_t
	LPCMP hysteresis mode. More...

typedef enum _lpcmp_power_mode	lpcmp_power_mode_t
	LPCMP nano mode.

typedef enum _lpcmp_dac_reference_voltage_source	lpcmp_dac_reference_voltage_source_t
	Internal DAC reference voltage source.

typedef struct _lpcmp_filter_config	lpcmp_filter_config_t
	Configure the filter.

typedef struct _lpcmp_dac_config	lpcmp_dac_config_t
	configure the internal DAC.

typedef struct _lpcmp_config	lpcmp_config_t
	Configures the comparator.

Enumerations
enum	_lpcmp_status_flags { kLPCMP_OutputRisingEventFlag = LPCMP_CSR_CFR_MASK, kLPCMP_OutputFallingEventFlag = LPCMP_CSR_CFF_MASK, kLPCMP_OutputAssertEventFlag = LPCMP_CSR_COUT_MASK }
	LPCMP status falgs mask. More...

enum	_lpcmp_interrupt_enable { kLPCMP_OutputRisingInterruptEnable = LPCMP_IER_CFR_IE_MASK, kLPCMP_OutputFallingInterruptEnable = LPCMP_IER_CFF_IE_MASK }
	LPCMP interrupt enable/disable mask. More...

enum	_lpcmp_hysteresis_mode { kLPCMP_HysteresisLevel0 = 0U, kLPCMP_HysteresisLevel1 = 1U, kLPCMP_HysteresisLevel2 = 2U, kLPCMP_HysteresisLevel3 = 3U }
	LPCMP hysteresis mode. More...

enum	_lpcmp_power_mode { kLPCMP_LowSpeedPowerMode = 0U, kLPCMP_HighSpeedPowerMode = 1U, kLPCMP_NanoPowerMode = 2U }
	LPCMP nano mode. More...

enum	_lpcmp_dac_reference_voltage_source { kLPCMP_VrefSourceVin1 = 0U, kLPCMP_VrefSourceVin2 = 1U }
	Internal DAC reference voltage source. More...

Driver version
#define	FSL_LPCMP_DRIVER_VERSION (MAKE_VERSION(2, 1, 1))
	LPCMP driver version 2.1.1. More...

Initialization and configuration
void	LPCMP_Init (LPCMP_Type base, const lpcmp_config_t config)
	Initialize the LPCMP. More...

void	LPCMP_Deinit (LPCMP_Type *base)
	De-initializes the LPCMP module. More...

void	LPCMP_GetDefaultConfig (lpcmp_config_t *config)
	Gets an available pre-defined settings for the comparator's configuration. More...

static void	LPCMP_Enable (LPCMP_Type *base, bool enable)
	Enable/Disable LPCMP module. More...

void	LPCMP_SetInputChannels (LPCMP_Type *base, uint32_t positiveChannel, uint32_t negativeChannel)
	Select the input channels for LPCMP. More...

static void	LPCMP_EnableDMA (LPCMP_Type *base, bool enable)
	Enables/disables the DMA request for rising/falling events. More...

void	LPCMP_SetFilterConfig (LPCMP_Type base, const lpcmp_filter_config_t config)
	Configures the filter. More...

void	LPCMP_SetDACConfig (LPCMP_Type base, const lpcmp_dac_config_t config)
	Configure the internal DAC module. More...

static void	LPCMP_EnableInterrupts (LPCMP_Type *base, uint32_t mask)
	Enable the interrupts. More...

static void	LPCMP_DisableInterrupts (LPCMP_Type *base, uint32_t mask)
	Disable the interrupts. More...

static uint32_t	LPCMP_GetStatusFlags (LPCMP_Type *base)
	Get the LPCMP status flags. More...

static void	LPCMP_ClearStatusFlags (LPCMP_Type *base, uint32_t mask)
	Clear the LPCMP status flags. More...

Window mode
static void	LPCMP_EnableWindowMode (LPCMP_Type *base, bool enable)
	Enable/Disable window mode.When any windowed mode is active, COUTA is clocked by the bus clock whenever WINDOW = 1. More...

Data Structure Documentation

struct _lpcmp_filter_config

Data Fields
bool	enableSample
	Decide whether to use the external SAMPLE as a sampling clock input. More...

uint8_t	filterSampleCount
	Filter Sample Count. More...

uint8_t	filterSamplePeriod
	Filter Sample Period. More...

Field Documentation

bool _lpcmp_filter_config::enableSample

uint8_t _lpcmp_filter_config::filterSampleCount

Available range is 1-7; 0 disables the filter.

uint8_t _lpcmp_filter_config::filterSamplePeriod

The divider to the bus clock. Available range is 0-255. The sampling clock must be at least 4 times slower than the system clock to the comparator. So if enableSample is "false", filterSamplePeriod should be set greater than 4.

struct _lpcmp_dac_config

Data Fields
bool	enableLowPowerMode
	Decide whether to enable DAC low power mode. More...

lpcmp_dac_reference_voltage_source_t	referenceVoltageSource
	Internal DAC supply voltage reference source. More...

uint8_t	DACValue
	Value for the DAC Output Voltage. More...

Field Documentation

bool _lpcmp_dac_config::enableLowPowerMode

lpcmp_dac_reference_voltage_source_t _lpcmp_dac_config::referenceVoltageSource

uint8_t _lpcmp_dac_config::DACValue

Different devices has different available range, for specific values, please refer to the reference manual.

struct _lpcmp_config

Data Fields
bool	enableStopMode
	Decide whether to enable the comparator when in STOP modes. More...

bool	enableOutputPin
	Decide whether to enable the comparator is available in selected pin. More...

bool	useUnfilteredOutput
	Decide whether to use unfiltered output. More...

bool	enableInvertOutput
	Decide whether to inverts the comparator output. More...

lpcmp_hysteresis_mode_t	hysteresisMode
	LPCMP hysteresis mode. More...

lpcmp_power_mode_t	powerMode
	LPCMP power mode. More...

Field Documentation

bool _lpcmp_config::enableStopMode

bool _lpcmp_config::enableOutputPin

bool _lpcmp_config::useUnfilteredOutput

bool _lpcmp_config::enableInvertOutput

lpcmp_hysteresis_mode_t _lpcmp_config::hysteresisMode

lpcmp_power_mode_t _lpcmp_config::powerMode

Macro Definition Documentation

#define FSL_LPCMP_DRIVER_VERSION (MAKE_VERSION(2, 1, 1))

Typedef Documentation

typedef enum _lpcmp_hysteresis_mode lpcmp_hysteresis_mode_t

See chip data sheet to get the actual hystersis value with each level

Enumeration Type Documentation

enum _lpcmp_status_flags

Enumerator

kLPCMP_OutputRisingEventFlag

Rising-edge on the comparison output has occurred.

kLPCMP_OutputFallingEventFlag

Falling-edge on the comparison output has occurred.

kLPCMP_OutputAssertEventFlag

Return the current value of the analog comparator output.

The flag does not support W1C.

enum _lpcmp_interrupt_enable

Enumerator
kLPCMP_OutputRisingInterruptEnable	Comparator interrupt enable rising.
kLPCMP_OutputFallingInterruptEnable	Comparator interrupt enable falling.

enum _lpcmp_hysteresis_mode

See chip data sheet to get the actual hystersis value with each level

Enumerator
kLPCMP_HysteresisLevel0	The hard block output has level 0 hysteresis internally.
kLPCMP_HysteresisLevel1	The hard block output has level 1 hysteresis internally.
kLPCMP_HysteresisLevel2	The hard block output has level 2 hysteresis internally.
kLPCMP_HysteresisLevel3	The hard block output has level 3 hysteresis internally.

enum _lpcmp_power_mode

Enumerator
kLPCMP_LowSpeedPowerMode	Low speed comparison mode is selected.
kLPCMP_HighSpeedPowerMode	High speed comparison mode is selected.
kLPCMP_NanoPowerMode	Nano power comparator is enabled.

enum _lpcmp_dac_reference_voltage_source

Enumerator
kLPCMP_VrefSourceVin1	vrefh_int is selected as resistor ladder network supply reference Vin.
kLPCMP_VrefSourceVin2	vrefh_ext is selected as resistor ladder network supply reference Vin.

Function Documentation

void LPCMP_Init	(	LPCMP_Type *	base,
		const lpcmp_config_t *	config
	)

This function initializes the LPCMP module. The operations included are:

Enabling the clock for LPCMP module.
Configuring the comparator.
Enabling the LPCMP module. Note: For some devices, multiple LPCMP instance share the same clock gate. In this case, to enable the clock for any instance enables all the LPCMPs. Check the chip reference manual for the clock assignment of the LPCMP.

Parameters

base	LPCMP peripheral base address.
config	Pointer to "lpcmp_config_t" structure.

void LPCMP_Deinit ( LPCMP_Type * base )

This function de-initializes the LPCMP module. The operations included are:

Disabling the LPCMP module.
Disabling the clock for LPCMP module.

This function disables the clock for the LPCMP. Note: For some devices, multiple LPCMP instance shares the same clock gate. In this case, before disabling the clock for the LPCMP, ensure that all the LPCMP instances are not used.

Parameters

base	LPCMP peripheral base address.

void LPCMP_GetDefaultConfig ( lpcmp_config_t * config )

This function initializes the comparator configuration structure to these default values:

*   config->enableStopMode      = false;
*   config->enableOutputPin     = false;
*   config->useUnfilteredOutput = false;
*   config->enableInvertOutput  = false;
*   config->hysteresisMode      = kLPCMP_HysteresisLevel0;
*   config->powerMode           = kLPCMP_LowSpeedPowerMode;
*   config->functionalSourceClock = kLPCMP_FunctionalClockSource0;
* 

Parameters

config Pointer to "lpcmp_config_t" structure.

static void LPCMP_Enable	(	LPCMP_Type *	base,
		bool	enable
	)

inlinestatic

Parameters

base	LPCMP peripheral base address.
enable	"true" means enable the module, and "false" means disable the module.

void LPCMP_SetInputChannels	(	LPCMP_Type *	base,
		uint32_t	positiveChannel,
		uint32_t	negativeChannel
	)

This function determines which input is selected for the negative and positive mux.

Parameters

base	LPCMP peripheral base address.
positiveChannel	Positive side input channel number. Available range is 0-7.
negativeChannel	Negative side input channel number. Available range is 0-7.

static void LPCMP_EnableDMA	(	LPCMP_Type *	base,
		bool	enable
	)

inlinestatic

   Normally, the LPCMP generates a CPU interrupt if there is a rising/falling event. When
   DMA support is enabled and the rising/falling interrupt is enabled , the rising/falling
   event forces a DMA transfer request rather than a CPU interrupt instead.

Parameters

base	LPCMP peripheral base address.
enable	"true" means enable DMA support, and "false" means disable DMA support.

void LPCMP_SetFilterConfig	(	LPCMP_Type *	base,
		const lpcmp_filter_config_t *	config
	)

Parameters

base	LPCMP peripheral base address.
config	Pointer to "lpcmp_filter_config_t" structure.

void LPCMP_SetDACConfig	(	LPCMP_Type *	base,
		const lpcmp_dac_config_t *	config
	)

Parameters

base	LPCMP peripheral base address.
config	Pointer to "lpcmp_dac_config_t" structure. If config is "NULL", disable internal DAC.

static void LPCMP_EnableInterrupts	(	LPCMP_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	LPCMP peripheral base address.
mask	Mask value for interrupts. See "_lpcmp_interrupt_enable".

static void LPCMP_DisableInterrupts	(	LPCMP_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	LPCMP peripheral base address.
mask	Mask value for interrupts. See "_lpcmp_interrupt_enable".

static uint32_t LPCMP_GetStatusFlags ( LPCMP_Type * base )

inlinestatic

Parameters

base	LPCMP peripheral base address.

Returns: Mask value for the asserted flags. See "_lpcmp_status_flags".

static void LPCMP_ClearStatusFlags	(	LPCMP_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	LPCMP peripheral base address.
mask	Mask value for the flags. See "_lpcmp_status_flags".

static void LPCMP_EnableWindowMode	(	LPCMP_Type *	base,
		bool	enable
	)

inlinestatic

The last latched value is held when WINDOW = 0. The optionally inverted comparator output COUT_RAW is sampled on every bus clock when WINDOW=1 to generate COUTA.

Parameters

base	LPCMP peripheral base address.
enable	"true" means enable window mode, and "false" means disable window mode.

Overview

Typical use case

Polling Configuration

Interrupt Configuration

Initialization and configuration

Window mode

RoundRobin mode

Data Structures

Typedefs

Enumerations

Driver version

Initialization and configuration

Window mode

Data Structure Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Macro Definition Documentation

Typedef Documentation

Enumeration Type Documentation

Function Documentation