Overview

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

The ACMP driver is created to help the user operate the ACMP module better. This driver can be considered as a basic comparator with advanced features. The APIs for basic comparator can make the CMP work as a general comparator, which compares the two input channel's voltage and creates the output of the comparator result immediately. The APIs for advanced feature can be used as the plug-in function based on the basic comparator, and can provide more ways to process the comparator's output.

Typical use case

Normal Configuration

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

Interrupt Configuration

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

Round robin Configuration

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

Data Structures
struct	acmp_config_t
	Configuration for ACMP. More...

struct	acmp_channel_config_t
	Configuration for channel. More...

struct	acmp_filter_config_t
	Configuration for filter. More...

struct	acmp_dac_config_t
	Configuration for DAC. More...

struct	acmp_round_robin_config_t
	Configuration for round robin mode. More...

struct	acmp_discrete_mode_config_t
	Configuration for discrete mode. More...

Macros
#define	CMP_C0_CFx_MASK (CMP_C0_CFR_MASK \| CMP_C0_CFF_MASK)
	The mask of status flags cleared by writing 1. More...

Enumerations
enum	_acmp_interrupt_enable { kACMP_OutputRisingInterruptEnable = (1U << 0U), kACMP_OutputFallingInterruptEnable = (1U << 1U), kACMP_RoundRobinInterruptEnable = (1U << 2U) }
	Interrupt enable/disable mask. More...

enum	_acmp_status_flags { kACMP_OutputRisingEventFlag = CMP_C0_CFR_MASK, kACMP_OutputFallingEventFlag = CMP_C0_CFF_MASK, kACMP_OutputAssertEventFlag = CMP_C0_COUT_MASK }
	Status flag mask. More...

enum	acmp_hysteresis_mode_t { kACMP_HysteresisLevel0 = 0U, kACMP_HysteresisLevel1 = 1U, kACMP_HysteresisLevel2 = 2U, kACMP_HysteresisLevel3 = 3U }
	Comparator hard block hysteresis control. More...

enum	acmp_reference_voltage_source_t { kACMP_VrefSourceVin1 = 0U, kACMP_VrefSourceVin2 = 1U }
	CMP Voltage Reference source. More...

enum	acmp_fixed_port_t { kACMP_FixedPlusPort = 0U, kACMP_FixedMinusPort = 1U }
	Fixed mux port. More...

enum	acmp_dac_work_mode_t { kACMP_DACWorkLowSpeedMode = 0U, kACMP_DACWorkHighSpeedMode = 1U }
	Internal DAC's work mode. More...

enum	acmp_discrete_clock_source_t { kACMP_DiscreteClockSlow = 0U, kACMP_DiscreteClockFast = 1U }
	Discrete mode clock selection. More...

enum	acmp_discrete_sample_time_t { kACMP_DiscreteSampleTimeAs1T = 0U, kACMP_DiscreteSampleTimeAs2T = 1U, kACMP_DiscreteSampleTimeAs4T = 2U, kACMP_DiscreteSampleTimeAs8T = 3U, kACMP_DiscreteSampleTimeAs16T = 4U, kACMP_DiscreteSampleTimeAs32T = 5U, kACMP_DiscreteSampleTimeAs64T = 6U, kACMP_DiscreteSampleTimeAs256T = 7U }
	ACMP discrete sample selection. More...

enum	acmp_discrete_phase_time_t { kACMP_DiscretePhaseTimeAlt0 = 0U, kACMP_DiscretePhaseTimeAlt1 = 1U, kACMP_DiscretePhaseTimeAlt2 = 2U, kACMP_DiscretePhaseTimeAlt3 = 3U, kACMP_DiscretePhaseTimeAlt4 = 4U, kACMP_DiscretePhaseTimeAlt5 = 5U, kACMP_DiscretePhaseTimeAlt6 = 6U, kACMP_DiscretePhaseTimeAlt7 = 7U }
	ACMP discrete phase time selection. More...

Driver version
#define	FSL_ACMP_DRIVER_VERSION (MAKE_VERSION(2U, 0U, 6U))
	ACMP driver version 2.0.6. More...

Initialization and deinitialization
void	ACMP_Init (CMP_Type base, const acmp_config_t config)
	Initializes the ACMP. More...

void	ACMP_Deinit (CMP_Type *base)
	Deinitializes the ACMP. More...

void	ACMP_GetDefaultConfig (acmp_config_t *config)
	Gets the default configuration for ACMP. More...

Basic Operations
void	ACMP_Enable (CMP_Type *base, bool enable)
	Enables or disables the ACMP. More...

void	ACMP_EnableLinkToDAC (CMP_Type *base, bool enable)
	Enables the link from CMP to DAC enable. More...

void	ACMP_SetChannelConfig (CMP_Type base, const acmp_channel_config_t config)
	Sets the channel configuration. More...

Advanced Operations
void	ACMP_EnableDMA (CMP_Type *base, bool enable)
	Enables or disables DMA. More...

void	ACMP_EnableWindowMode (CMP_Type *base, bool enable)
	Enables or disables window mode. More...

void	ACMP_SetFilterConfig (CMP_Type base, const acmp_filter_config_t config)
	Configures the filter. More...

void	ACMP_SetDACConfig (CMP_Type base, const acmp_dac_config_t config)
	Configures the internal DAC. More...

void	ACMP_SetRoundRobinConfig (CMP_Type base, const acmp_round_robin_config_t config)
	Configures the round robin mode. More...

void	ACMP_SetRoundRobinPreState (CMP_Type *base, uint32_t mask)
	Defines the pre-set state of channels in round robin mode. More...

static uint32_t	ACMP_GetRoundRobinStatusFlags (CMP_Type *base)
	Gets the channel input changed flags in round robin mode. More...

void	ACMP_ClearRoundRobinStatusFlags (CMP_Type *base, uint32_t mask)
	Clears the channel input changed flags in round robin mode. More...

static uint32_t	ACMP_GetRoundRobinResult (CMP_Type *base)
	Gets the round robin result. More...

Interrupts
void	ACMP_EnableInterrupts (CMP_Type *base, uint32_t mask)
	Enables interrupts. More...

void	ACMP_DisableInterrupts (CMP_Type *base, uint32_t mask)
	Disables interrupts. More...

Status
uint32_t	ACMP_GetStatusFlags (CMP_Type *base)
	Gets status flags. More...

void	ACMP_ClearStatusFlags (CMP_Type *base, uint32_t mask)
	Clears status flags. More...

Discrete mode
void	ACMP_SetDiscreteModeConfig (CMP_Type base, const acmp_discrete_mode_config_t config)
	Configure the discrete mode. More...

void	ACMP_GetDefaultDiscreteModeConfig (acmp_discrete_mode_config_t *config)
	Get the default configuration for discrete mode setting. More...

Data Structure Documentation

struct acmp_config_t

Data Fields
acmp_hysteresis_mode_t	hysteresisMode
	Hysteresis mode. More...

bool	enableHighSpeed
	Enable High Speed (HS) comparison mode. More...

bool	enableInvertOutput
	Enable inverted comparator output. More...

bool	useUnfilteredOutput
	Set compare output(COUT) to equal COUTA(true) or COUT(false). More...

bool	enablePinOut
	The comparator output is available on the associated pin. More...

Field Documentation

acmp_hysteresis_mode_t acmp_config_t::hysteresisMode

bool acmp_config_t::enableHighSpeed

bool acmp_config_t::enableInvertOutput

bool acmp_config_t::useUnfilteredOutput

bool acmp_config_t::enablePinOut

struct acmp_channel_config_t

The comparator's port can be input from channel mux or DAC. If port input is from channel mux, detailed channel number for the mux should be configured.

Data Fields
uint32_t	plusMuxInput
	Plus mux input channel(0~7). More...

uint32_t	minusMuxInput
	Minus mux input channel(0~7). More...

Field Documentation

uint32_t acmp_channel_config_t::plusMuxInput

uint32_t acmp_channel_config_t::minusMuxInput

struct acmp_filter_config_t

Data Fields
bool	enableSample
	Using external SAMPLE as sampling clock input, or using divided bus clock. More...

uint32_t	filterCount
	Filter Sample Count. More...

uint32_t	filterPeriod
	Filter Sample Period. More...

Field Documentation

bool acmp_filter_config_t::enableSample

uint32_t acmp_filter_config_t::filterCount

Available range is 1-7, 0 would cause the filter disabled.

uint32_t acmp_filter_config_t::filterPeriod

The divider to bus clock. Available range is 0-255.

struct acmp_dac_config_t

Data Fields
acmp_reference_voltage_source_t	referenceVoltageSource
	Supply voltage reference source. More...

uint32_t	DACValue
	Value for DAC Output Voltage. More...

Field Documentation

acmp_reference_voltage_source_t acmp_dac_config_t::referenceVoltageSource

uint32_t acmp_dac_config_t::DACValue

Available range is 0-255.

struct acmp_round_robin_config_t

Data Fields
acmp_fixed_port_t	fixedPort
	Fixed mux port. More...

uint32_t	fixedChannelNumber
	Indicates which channel is fixed in the fixed mux port. More...

uint32_t	checkerChannelMask
	Mask of checker channel index. More...

uint32_t	sampleClockCount
	Specifies how many round-robin clock cycles(0~3) later the sample takes place. More...

uint32_t	delayModulus
	Comparator and DAC initialization delay modulus. More...

Field Documentation

acmp_fixed_port_t acmp_round_robin_config_t::fixedPort

uint32_t acmp_round_robin_config_t::fixedChannelNumber

uint32_t acmp_round_robin_config_t::checkerChannelMask

Available range is channel0:0x01 to channel7:0x80 for round-robin checker.

uint32_t acmp_round_robin_config_t::sampleClockCount

uint32_t acmp_round_robin_config_t::delayModulus

struct acmp_discrete_mode_config_t

Data Fields
bool	enablePositiveChannelDiscreteMode
	Positive Channel Continuous Mode Enable. More...

bool	enableNegativeChannelDiscreteMode
	Negative Channel Continuous Mode Enable. More...

bool	enableResistorDivider
	Resistor Divider Enable is used to enable the resistor divider for the inputs when they come from 3v domain and their values are above 1.8v. More...

acmp_discrete_clock_source_t	clockSource
	Select the clock source in order to generate the requiried timing for comparator to work in discrete mode. More...

acmp_discrete_sample_time_t	sampleTime
	Select the ACMP total sampling time period. More...

acmp_discrete_phase_time_t	phase1Time
	Select the ACMP phase 1 sampling time. More...

acmp_discrete_phase_time_t	phase2Time
	Select the ACMP phase 2 sampling time. More...

Field Documentation

bool acmp_discrete_mode_config_t::enablePositiveChannelDiscreteMode

By default, the continuous mode is used.

bool acmp_discrete_mode_config_t::enableNegativeChannelDiscreteMode

By default, the continuous mode is used.

bool acmp_discrete_mode_config_t::enableResistorDivider

acmp_discrete_clock_source_t acmp_discrete_mode_config_t::clockSource

acmp_discrete_sample_time_t acmp_discrete_mode_config_t::sampleTime

acmp_discrete_phase_time_t acmp_discrete_mode_config_t::phase1Time

acmp_discrete_phase_time_t acmp_discrete_mode_config_t::phase2Time

Macro Definition Documentation

#define FSL_ACMP_DRIVER_VERSION (MAKE_VERSION(2U, 0U, 6U))

#define CMP_C0_CFx_MASK (CMP_C0_CFR_MASK | CMP_C0_CFF_MASK)

Enumeration Type Documentation

enum _acmp_interrupt_enable

Enumerator
kACMP_OutputRisingInterruptEnable	Enable the interrupt when comparator outputs rising.
kACMP_OutputFallingInterruptEnable	Enable the interrupt when comparator outputs falling.
kACMP_RoundRobinInterruptEnable	Enable the Round-Robin interrupt.

enum _acmp_status_flags

Enumerator
kACMP_OutputRisingEventFlag	Rising-edge on compare output has occurred.
kACMP_OutputFallingEventFlag	Falling-edge on compare output has occurred.
kACMP_OutputAssertEventFlag	Return the current value of the analog comparator output.

enum acmp_hysteresis_mode_t

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

Enumerator
kACMP_HysteresisLevel0	Offset is level 0 and Hysteresis is level 0.
kACMP_HysteresisLevel1	Offset is level 0 and Hysteresis is level 1.
kACMP_HysteresisLevel2	Offset is level 0 and Hysteresis is level 2.
kACMP_HysteresisLevel3	Offset is level 0 and Hysteresis is level 3.

enum acmp_reference_voltage_source_t

Enumerator
kACMP_VrefSourceVin1	Vin1 is selected as resistor ladder network supply reference Vin.
kACMP_VrefSourceVin2	Vin2 is selected as resistor ladder network supply reference Vin.

enum acmp_fixed_port_t

Enumerator
kACMP_FixedPlusPort	Only the inputs to the Minus port are swept in each round.
kACMP_FixedMinusPort	Only the inputs to the Plus port are swept in each round.

enum acmp_dac_work_mode_t

Enumerator
kACMP_DACWorkLowSpeedMode	DAC is selected to work in low speed and low power mode.
kACMP_DACWorkHighSpeedMode	DAC is selected to work in high speed high power mode.

enum acmp_discrete_clock_source_t

Enumerator
kACMP_DiscreteClockSlow	Slow clock (32kHz) is used as the discrete mode clock.
kACMP_DiscreteClockFast	Fast clock (16-20MHz) is used as the discrete mode clock.

enum acmp_discrete_sample_time_t

These values configures the analog comparator sampling timing (speicified by the discrete mode clock period T which is selected by acmp_discrete_clock_source_t) in discrete mode.

Enumerator
kACMP_DiscreteSampleTimeAs1T	The sampling time equals to 1xT.
kACMP_DiscreteSampleTimeAs2T	The sampling time equals to 2xT.
kACMP_DiscreteSampleTimeAs4T	The sampling time equals to 4xT.
kACMP_DiscreteSampleTimeAs8T	The sampling time equals to 8xT.
kACMP_DiscreteSampleTimeAs16T	The sampling time equals to 16xT.
kACMP_DiscreteSampleTimeAs32T	The sampling time equals to 32xT.
kACMP_DiscreteSampleTimeAs64T	The sampling time equals to 64xT.
kACMP_DiscreteSampleTimeAs256T	The sampling time equals to 256xT.

enum acmp_discrete_phase_time_t

There are two phases for sampling input signals, phase 1 and phase 2.

Enumerator
kACMP_DiscretePhaseTimeAlt0	The phase x active in one sampling selection 0.
kACMP_DiscretePhaseTimeAlt1	The phase x active in one sampling selection 1.
kACMP_DiscretePhaseTimeAlt2	The phase x active in one sampling selection 2.
kACMP_DiscretePhaseTimeAlt3	The phase x active in one sampling selection 3.
kACMP_DiscretePhaseTimeAlt4	The phase x active in one sampling selection 4.
kACMP_DiscretePhaseTimeAlt5	The phase x active in one sampling selection 5.
kACMP_DiscretePhaseTimeAlt6	The phase x active in one sampling selection 6.
kACMP_DiscretePhaseTimeAlt7	The phase x active in one sampling selection 7.

Function Documentation

void ACMP_Init	(	CMP_Type *	base,
		const acmp_config_t *	config
	)

The default configuration can be got by calling ACMP_GetDefaultConfig().

Parameters

base	ACMP peripheral base address.
config	Pointer to ACMP configuration structure.

void ACMP_Deinit ( CMP_Type * base )

Parameters

base	ACMP peripheral base address.

void ACMP_GetDefaultConfig ( acmp_config_t * config )

This function initializes the user configuration structure to default value. The default value are:

Example:

config->enableHighSpeed = false;
config->enableInvertOutput = false;
config->useUnfilteredOutput = false;
config->enablePinOut = false;
config->enableHysteresisBothDirections = false;
config->hysteresisMode = kACMP_hysteresisMode0;

Parameters

config Pointer to ACMP configuration structure.

void ACMP_Enable	(	CMP_Type *	base,
		bool	enable
	)

Parameters

base	ACMP peripheral base address.
enable	True to enable the ACMP.

void ACMP_EnableLinkToDAC	(	CMP_Type *	base,
		bool	enable
	)

When this bit is set, the DAC enable/disable is controlled by the bit CMP_C0[EN] instead of CMP_C1[DACEN].

Parameters

base	ACMP peripheral base address.
enable	Enable the feature or not.

void ACMP_SetChannelConfig	(	CMP_Type *	base,
		const acmp_channel_config_t *	config
	)

Note that the plus/minus mux's setting is only valid when the positive/negative port's input isn't from DAC but from channel mux.

Example:

acmp_channel_config_t configStruct = {0};
configStruct.positivePortInput = kACMP_PortInputFromDAC;
configStruct.negativePortInput = kACMP_PortInputFromMux;
configStruct.minusMuxInput = 1U;
ACMP_SetChannelConfig(CMP0, &configStruct);

Parameters

base	ACMP peripheral base address.
config	Pointer to channel configuration structure.

void ACMP_EnableDMA	(	CMP_Type *	base,
		bool	enable
	)

Parameters

base	ACMP peripheral base address.
enable	True to enable DMA.

void ACMP_EnableWindowMode	(	CMP_Type *	base,
		bool	enable
	)

Parameters

base	ACMP peripheral base address.
enable	True to enable window mode.

void ACMP_SetFilterConfig	(	CMP_Type *	base,
		const acmp_filter_config_t *	config
	)

The filter can be enabled when the filter count is bigger than 1, the filter period is greater than 0 and the sample clock is from divided bus clock or the filter is bigger than 1 and the sample clock is from external clock. Detailed usage can be got from the reference manual.

Example:

acmp_filter_config_t configStruct = {0};
configStruct.filterCount = 5U;
configStruct.filterPeriod = 200U;
configStruct.enableSample = false;
ACMP_SetFilterConfig(CMP0, &configStruct);

Parameters

base	ACMP peripheral base address.
config	Pointer to filter configuration structure.

void ACMP_SetDACConfig	(	CMP_Type *	base,
		const acmp_dac_config_t *	config
	)

Example:

acmp_dac_config_t configStruct = {0};
configStruct.referenceVoltageSource = kACMP_VrefSourceVin1;
configStruct.DACValue = 20U;
configStruct.enableOutput = false;
configStruct.workMode = kACMP_DACWorkLowSpeedMode;
ACMP_SetDACConfig(CMP0, &configStruct);

Parameters

base	ACMP peripheral base address.
config	Pointer to DAC configuration structure. "NULL" is for disabling the feature.

void ACMP_SetRoundRobinConfig	(	CMP_Type *	base,
		const acmp_round_robin_config_t *	config
	)

Example:

acmp_round_robin_config_t configStruct = {0};
configStruct.fixedPort = kACMP_FixedPlusPort;
configStruct.fixedChannelNumber = 3U;
configStruct.checkerChannelMask = 0xF7U;
configStruct.sampleClockCount = 0U;
configStruct.delayModulus = 0U;
ACMP_SetRoundRobinConfig(CMP0, &configStruct);

Parameters

base	ACMP peripheral base address.
config	Pointer to round robin mode configuration structure. "NULL" is for disabling the feature.

void ACMP_SetRoundRobinPreState	(	CMP_Type *	base,
		uint32_t	mask
	)

Note: The pre-state has different circuit with get-round-robin-result in the SOC even though they are same bits. So get-round-robin-result can't return the same value as the value are set by pre-state.

Parameters

base	ACMP peripheral base address.
mask	Mask of round robin channel index. Available range is channel0:0x01 to channel7:0x80.

static uint32_t ACMP_GetRoundRobinStatusFlags ( CMP_Type * base )

inlinestatic

Parameters

base	ACMP peripheral base address.

Returns: Mask of channel input changed asserted flags. Available range is channel0:0x01 to channel7:0x80.

void ACMP_ClearRoundRobinStatusFlags	(	CMP_Type *	base,
		uint32_t	mask
	)

Parameters

base	ACMP peripheral base address.
mask	Mask of channel index. Available range is channel0:0x01 to channel7:0x80.

static uint32_t ACMP_GetRoundRobinResult ( CMP_Type * base )

inlinestatic

Note that the set-pre-state has different circuit with get-round-robin-result in the SOC even though they are same bits. So ACMP_GetRoundRobinResult() can't return the same value as the value are set by ACMP_SetRoundRobinPreState.

Parameters

base	ACMP peripheral base address.

Returns: Mask of round robin channel result. Available range is channel0:0x01 to channel7:0x80.

void ACMP_EnableInterrupts	(	CMP_Type *	base,
		uint32_t	mask
	)

Parameters

base	ACMP peripheral base address.
mask	Interrupts mask. See "_acmp_interrupt_enable".

void ACMP_DisableInterrupts	(	CMP_Type *	base,
		uint32_t	mask
	)

Parameters

base	ACMP peripheral base address.
mask	Interrupts mask. See "_acmp_interrupt_enable".

uint32_t ACMP_GetStatusFlags ( CMP_Type * base )

Parameters

base	ACMP peripheral base address.

Returns: Status flags asserted mask. See "_acmp_status_flags".

void ACMP_ClearStatusFlags	(	CMP_Type *	base,
		uint32_t	mask
	)

Parameters

base	ACMP peripheral base address.
mask	Status flags mask. See "_acmp_status_flags".

void ACMP_SetDiscreteModeConfig	(	CMP_Type *	base,
		const acmp_discrete_mode_config_t *	config
	)

Configure the discrete mode when supporting 3V domain with 1.8V core.

Parameters

base	ACMP peripheral base address.
config	Pointer to configuration structure. See "acmp_discrete_mode_config_t".

void ACMP_GetDefaultDiscreteModeConfig ( acmp_discrete_mode_config_t * config )

Parameters

config Pointer to configuration structure to be restored with the setting values.

Overview

Typical use case

Normal Configuration

Interrupt Configuration

Round robin Configuration

Data Structures

Macros

Enumerations

Driver version

Initialization and deinitialization

Basic Operations

Advanced Operations

Interrupts

Status

Discrete mode

Data Structure Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Macro Definition Documentation

Enumeration Type Documentation

Function Documentation