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
	Configuration for ACMP. More...

struct	_acmp_channel_config
	Configuration for channel. More...

struct	_acmp_filter_config
	Configuration for filter. More...

struct	_acmp_dac_config
	Configuration for DAC. More...

struct	_acmp_round_robin_config
	Configuration for round robin 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...

Typedefs
typedef enum _acmp_offset_mode	acmp_offset_mode_t
	Comparator hard block offset control. More...

typedef enum _acmp_hysteresis_mode	acmp_hysteresis_mode_t
	Comparator hard block hysteresis control. More...

typedef enum _acmp_reference_voltage_source	acmp_reference_voltage_source_t
	CMP Voltage Reference source. More...

typedef enum _acmp_port_input	acmp_port_input_t
	Port input source. More...

typedef enum _acmp_fixed_port	acmp_fixed_port_t
	Fixed mux port. More...

typedef struct _acmp_config	acmp_config_t
	Configuration for ACMP. More...

typedef struct _acmp_channel_config	acmp_channel_config_t
	Configuration for channel. More...

typedef struct _acmp_filter_config	acmp_filter_config_t
	Configuration for filter. More...

typedef struct _acmp_dac_config	acmp_dac_config_t
	Configuration for DAC. More...

typedef struct _acmp_round_robin_config	acmp_round_robin_config_t
	Configuration for round robin mode. 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_offset_mode { kACMP_OffsetLevel0 = 0U, kACMP_OffsetLevel1 = 1U }
	Comparator hard block offset control. More...

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

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

enum	_acmp_port_input { kACMP_PortInputFromDAC = 0U, kACMP_PortInputFromMux = 1U }
	Port input source. More...

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

Driver version
#define	FSL_ACMP_DRIVER_VERSION (MAKE_VERSION(2, 3, 0))
	ACMP driver version 2.3.0. 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_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...

Data Structure Documentation

struct _acmp_config

Data Fields
acmp_offset_mode_t	offsetMode
	Offset mode. More...

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_offset_mode_t _acmp_config::offsetMode

acmp_hysteresis_mode_t _acmp_config::hysteresisMode

bool _acmp_config::enableHighSpeed

bool _acmp_config::enableInvertOutput

bool _acmp_config::useUnfilteredOutput

bool _acmp_config::enablePinOut

struct _acmp_channel_config

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
acmp_port_input_t	positivePortInput
	Input source of the comparator's positive port. More...

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

acmp_port_input_t	negativePortInput
	Input source of the comparator's negative port. More...

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

Field Documentation

acmp_port_input_t _acmp_channel_config::positivePortInput

uint32_t _acmp_channel_config::plusMuxInput

acmp_port_input_t _acmp_channel_config::negativePortInput

uint32_t _acmp_channel_config::minusMuxInput

struct _acmp_filter_config

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::enableSample

uint32_t _acmp_filter_config::filterCount

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

uint32_t _acmp_filter_config::filterPeriod

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

struct _acmp_dac_config

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::referenceVoltageSource

uint32_t _acmp_dac_config::DACValue

Available range is 0-255.

struct _acmp_round_robin_config

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::fixedPort

uint32_t _acmp_round_robin_config::fixedChannelNumber

uint32_t _acmp_round_robin_config::checkerChannelMask

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

uint32_t _acmp_round_robin_config::sampleClockCount

uint32_t _acmp_round_robin_config::delayModulus

Macro Definition Documentation

#define FSL_ACMP_DRIVER_VERSION (MAKE_VERSION(2, 3, 0))

#define CMP_C0_CFx_MASK (CMP_C0_CFR_MASK | CMP_C0_CFF_MASK)

Typedef Documentation

typedef enum _acmp_offset_mode acmp_offset_mode_t

If OFFSET level is 1, then there is no hysteresis in the case of positive port input crossing negative port input in the positive direction (or negative port input crossing positive port input in the negative direction). Hysteresis still exists for positive port input crossing negative port input in the falling direction. If OFFSET level is 0, then the hysteresis selected by acmp_hysteresis_mode_t is valid for both directions.

typedef enum _acmp_hysteresis_mode acmp_hysteresis_mode_t

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

typedef enum _acmp_reference_voltage_source acmp_reference_voltage_source_t

typedef enum _acmp_port_input acmp_port_input_t

typedef enum _acmp_fixed_port acmp_fixed_port_t

typedef struct _acmp_config acmp_config_t

typedef struct _acmp_channel_config 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.

typedef struct _acmp_filter_config acmp_filter_config_t

typedef struct _acmp_dac_config acmp_dac_config_t

typedef struct _acmp_round_robin_config acmp_round_robin_config_t

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_offset_mode

If OFFSET level is 1, then there is no hysteresis in the case of positive port input crossing negative port input in the positive direction (or negative port input crossing positive port input in the negative direction). Hysteresis still exists for positive port input crossing negative port input in the falling direction. If OFFSET level is 0, then the hysteresis selected by acmp_hysteresis_mode_t is valid for both directions.

Enumerator
kACMP_OffsetLevel0	The comparator hard block output has level 0 offset internally.
kACMP_OffsetLevel1	The comparator hard block output has level 1 offset internally.

enum _acmp_hysteresis_mode

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

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_port_input

Enumerator
kACMP_PortInputFromDAC	Port input from the 8-bit DAC output.
kACMP_PortInputFromMux	Port input from the analog 8-1 mux.

enum _acmp_fixed_port

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.

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_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".

Overview

Typical use case

Normal Configuration

Interrupt Configuration

Round robin Configuration

Data Structures

Macros

Typedefs

Enumerations

Driver version

Initialization and deinitialization

Basic Operations

Advanced Operations

Interrupts

Status

Data Structure Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Macro Definition Documentation

Typedef Documentation

Enumeration Type Documentation

Function Documentation