Management and configuration functions for the ADC module.

The API functions and definitions can be divided in three groups:

interrupt callback: configure and set interrupt callback function.
module management: direct access for enabling and disabling the ADC, starting conversions, getting interrupt flags, etc.
module configuration: create/change configurations and write/read them to/from an ADC.

Data Structures
struct	adc_config
	ADC configuration. More...

Macros
#define	ADC_NR_OF_CHANNELS 4
	Number of channels per ADC. More...

Enumerations
enum	adc_calibration_data { ADC_CAL_ADCA, ADC_CAL_ADCB, ADC_CAL_TEMPSENSE, ADC_CAL_HOTTEMP, ADC_CAL_TEMPSENSE2, ADC_CAL_ROOMTEMP }
	ADC calibration data. More...

enum	adc_reference { ADC_REF_BANDGAP = ADC_REFSEL_INT1V_gc, ADC_REF_VCC = ADC_REFSEL_INTVCC_gc, ADC_REF_AREFA = ADC_REFSEL_AREFA_gc, ADC_REF_AREFB = ADC_REFSEL_AREFB_gc, ADC_REF_VCCDIV2 = ADC_REFSEL_VCCDIV2_gc }
	ADC reference settings. More...

enum	adc_resolution { ADC_RES_8 = ADC_RESOLUTION_8BIT_gc, ADC_RES_12 = ADC_RESOLUTION_12BIT_gc, ADC_RES_12_LEFT = ADC_RESOLUTION_LEFT12BIT_gc }
	ADC resolution settings. More...

enum	adc_sign { ADC_SIGN_OFF, ADC_SIGN_ON = ADC_CONMODE_bm }
	ADC signedness settings. More...

enum	adc_trigger { ADC_TRIG_MANUAL, ADC_TRIG_FREERUN, ADC_TRIG_EVENT_SINGLE, ADC_TRIG_FREERUN_SWEEP, ADC_TRIG_EVENT_SWEEP, ADC_TRIG_EVENT_SYNCSWEEP }
	ADC conversion trigger settings. More...

Calibration data addresses
Note The temperature sensor calibration is sampled at 85 degrees Celsius with unsigned, 12-bit conversion.
#define	ADCACAL0 offsetof(NVM_PROD_SIGNATURES_t, ADCACAL0)
	ADC A, calibration byte 0. More...

#define	ADCACAL1 offsetof(NVM_PROD_SIGNATURES_t, ADCACAL1)
	ADC A, calibration byte 1. More...

#define	ADCBCAL0 offsetof(NVM_PROD_SIGNATURES_t, ADCBCAL0)
	ADC B, calibration byte 0. More...

#define	ADCBCAL1 offsetof(NVM_PROD_SIGNATURES_t, ADCBCAL1)
	ADC B, calibration byte 1. More...

#define	TEMPSENSE0 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE0)
	Temperature sensor calibration byte 0. More...

#define	TEMPSENSE1 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE1)
	Temperature sensor calibration byte 1. More...

#define	HOTTEMP offsetof(NVM_PROD_SIGNATURES_t, HOTTEMP)
	Temperature at which TEMPSENSE1/TEMPSENSE0 is measured. More...

#define	ROOMTEMP offsetof(NVM_PROD_SIGNATURES_t, ROOMTEMP)
	Temperature at which TEMPSENSE3/TEMPSENSE2 is measured. More...

#define	TEMPSENSE2 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE2)
	Temperature sensor calibration byte 2. More...

#define	TEMPSENSE3 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE3)
	Temperature sensor calibration byte 3. More...

ADC channel masks
#define	ADC_CH0 (1U << 0)
	ADC channel 0. More...

#define	ADC_CH1 (1U << 1)
	ADC channel 1. More...

#define	ADC_CH2 (1U << 2)
	ADC channel 2. More...

#define	ADC_CH3 (1U << 3)
	ADC channel 3. More...

Internal ADC input masks
#define	ADC_INT_TEMPSENSE ADC_TEMPREF_bm
	Temperature sensor. More...

#define	ADC_INT_BANDGAP ADC_BANDGAP_bm
	Bandgap reference. More...

Internal functions for driver
static __always_inline ADC_CH_t *	adc_get_channel (ADC_t *adc, uint8_t ch_mask)
	Get ADC channel pointer from channel mask. More...

ADC interrupt callback function
typedef CONFIG_ADC_CALLBACK_TYPE	adc_result_t
	Datatype of ADC conversion result parameter for callback. More...

typedef void(*	adc_callback_t )(ADC_t *adc, uint8_t ch_mask, adc_result_t res)
	ADC interrupt callback function pointer. More...

void	adc_set_callback (ADC_t *adc, adc_callback_t callback)
	Set ADC interrupt callback function. More...

#define	CONFIG_ADC_CALLBACK_ENABLE
	Configuration symbol to enable callback on ADC interrupts. More...

#define	CONFIG_ADC_CALLBACK_TYPE uint16_t
	Configuration symbol for datatype of result parameter for callback. More...

ADC module management
void	adc_enable (ADC_t *adc)
	Enable ADC. More...

void	adc_disable (ADC_t *adc)
	Disable ADC. More...

bool	adc_is_enabled (ADC_t *adc)
	Check if the ADC is enabled. More...

static void	adc_start_conversion (ADC_t *adc, uint8_t ch_mask)
	Start one-shot conversion on ADC channel(s) More...

static int16_t	adc_get_signed_result (ADC_t *adc, uint8_t ch_mask)
	Get signed result from ADC channel. More...

static uint16_t	adc_get_unsigned_result (ADC_t *adc, uint8_t ch_mask)
	Get unsigned result from ADC channel. More...

static uint8_t	adc_get_interrupt_flag (ADC_t *adc, uint8_t ch_mask)
	Get interrupt flag of ADC channel(s) More...

static void	adc_clear_interrupt_flag (ADC_t *adc, uint8_t ch_mask)
	Clear interrupt flag of ADC channel(s) More...

static void	adc_wait_for_interrupt_flag (ADC_t *adc, uint8_t ch_mask)
	Wait for interrupt flag of ADC channel(s) More...

static void	adc_flush (ADC_t *adc)
	Flush the ADC. More...

static int16_t	adc_get_signed_compare_value (ADC_t *adc)
	Get signed compare value directly from ADC. More...

static uint16_t	adc_get_unsigned_compare_value (ADC_t *adc)
	Get unsigned compare value directly from ADC. More...

static uint16_t	adc_get_calibration_data (enum adc_calibration_data cal)
	Get calibration data. More...

#define	adc_get_result(adc, ch_mask) (adc_get_channel(adc, ch_mask)->RES)
	Get result from ADC channel. More...

#define	adc_set_compare_value(adc, val)
	Set compare value directly to ADC. More...

#define	adc_get_compare_value(adc) ((adc)->CMP)
	Get compare value directly from ADC. More...

ADC module configuration
enum	adc_gainstage_impmode { ADC_GAIN_HIGHIMPEDANCE, ADC_GAIN_LOWIMPEDANCE }
	ADC gain stage impedance settings. More...

enum	adc_current_limit { ADC_CURRENT_LIMIT_NO, ADC_CURRENT_LIMIT_LOW, ADC_CURRENT_LIMIT_MED, ADC_CURRENT_LIMIT_HIGH }
	ADC current limit settings. More...

void	adc_write_configuration (ADC_t adc, const struct adc_config conf)
	Write configuration to ADC module. More...

void	adc_read_configuration (ADC_t adc, struct adc_config conf)
	Read configuration from ADC module. More...

static void	adc_set_clock_rate (struct adc_config *conf, uint32_t clk_adc)
	Set ADC prescaler to get desired clock rate. More...

static void	adc_set_conversion_parameters (struct adc_config *conf, enum adc_sign sign, enum adc_resolution res, enum adc_reference ref)
	Set ADC conversion parameters. More...

static void	adc_set_conversion_trigger (struct adc_config *conf, enum adc_trigger trig, uint8_t nr_of_ch, uint8_t base_ev_ch)
	Set ADC conversion trigger. More...

static void	adc_set_dma_request_group (struct adc_config *conf, uint8_t nr_of_ch)
	Set DMA request group. More...

static void	adc_enable_internal_input (struct adc_config *conf, uint8_t int_inp)
	Enable internal ADC input. More...

static void	adc_disable_internal_input (struct adc_config *conf, uint8_t int_inp)
	Disable internal ADC input. More...

static void	adc_set_gain_impedance_mode (struct adc_config *conf, enum adc_gainstage_impmode impmode)
	Set ADC gain stage impedance mode. More...

static void	adc_set_current_limit (struct adc_config *conf, enum adc_current_limit currlimit)
	Set ADC current limit. More...

#define	adc_set_config_compare_value(conf, val)
	Set ADC compare value in configuration. More...

#define	adc_get_config_compare_value(conf) (conf->cmp)
	Get ADC compare value from configuration. More...

#define ADC_CH0 (1U << 0)

ADC channel 0.

Referenced by adcch_read_configuration(), adcch_write_configuration(), get_mean_sample_value(), ISR(), and main().

#define ADC_CH1 (1U << 1)

ADC channel 1.

#define ADC_CH2 (1U << 2)

ADC channel 2.

#define ADC_CH3 (1U << 3)

ADC channel 3.

#define adc_get_compare_value ( adc ) ((adc)->CMP)

Get compare value directly from ADC.

Gets the compare value directly from the ADC, for quick access while the ADC is enabled.

Parameters

adc	Pointer to ADC module.

Returns: Current compare value of the ADC. Signedness does not matter.

Note: This macro does not protect the 16-bit read from interrupts. If an interrupt may do a 16-bit read or write to the ADC while this macro is executing, interrupts must be temporarily disabled to avoid corruption of the read.

#define adc_get_config_compare_value ( conf ) (conf->cmp)

Get ADC compare value from configuration.

Parameters

conf	Pointer to ADC module configuration.

#define adc_get_result	(	adc,
		ch_mask
	)	(adc_get_channel(adc, ch_mask)->RES)

Get result from ADC channel.

Gets the latest conversion result from the ADC channel.

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (Only a single channel can be given in mask)

Returns: Latest conversion result of ADC channel. Signedness does not matter.

Note: This macro does not protect the 16-bit read from interrupts. If an interrupt may do a 16-bit read or write to the ADC while this macro is executing, interrupts must be temporarily disabled to avoid corruption of the read.

Referenced by differential_signed_average(), get_mean_sample_value(), ISR(), and single_ended_unsigned_average().

#define ADC_INT_BANDGAP ADC_BANDGAP_bm

Bandgap reference.

#define ADC_INT_TEMPSENSE ADC_TEMPREF_bm

Temperature sensor.

Referenced by main().

#define ADC_NR_OF_CHANNELS 4

Number of channels per ADC.

Referenced by adc_get_channel(), adc_set_conversion_trigger(), and adc_set_dma_request_group().

#define adc_set_compare_value	(	adc,
		val
	)

Value:

do { \
		irqflags_t ATPASTE2(adc_flags, __LINE__) =  cpu_irq_save(); \
        (adc)->CMP = val; \
		cpu_irq_restore(ATPASTE2(adc_flags, __LINE__));   \
    } \
    while (0)

Set compare value directly to ADC.

Sets the compare value directly to the ADC, for quick access while the ADC is enabled.

Parameters

adc	Pointer to ADC module.
val	Compare value to set, either signed or unsigned.

Note: The ADC must be enabled for this function to have any effect.

#define adc_set_config_compare_value	(	conf,
		val
	)

Value:

do { \
        conf->cmp = (uint16_t)val; \
    } \
    while (0)

Set ADC compare value in configuration.

Parameters

conf	Pointer to ADC module configuration.
val	Compare value to set.

#define ADCACAL0 offsetof(NVM_PROD_SIGNATURES_t, ADCACAL0)

ADC A, calibration byte 0.

Referenced by adc_get_calibration_data().

#define ADCACAL1 offsetof(NVM_PROD_SIGNATURES_t, ADCACAL1)

ADC A, calibration byte 1.

Referenced by adc_get_calibration_data().

#define ADCBCAL0 offsetof(NVM_PROD_SIGNATURES_t, ADCBCAL0)

ADC B, calibration byte 0.

Referenced by adc_get_calibration_data().

#define ADCBCAL1 offsetof(NVM_PROD_SIGNATURES_t, ADCBCAL1)

ADC B, calibration byte 1.

Referenced by adc_get_calibration_data().

#define CONFIG_ADC_CALLBACK_ENABLE

Configuration symbol to enable callback on ADC interrupts.

Define this symbol in conf_adc.h to enable callbacks on ADC interrupts. A function of type adc_callback_t must be defined by the user, and the driver be configured to use it with adc_set_callback.

#define CONFIG_ADC_CALLBACK_TYPE uint16_t

Configuration symbol for datatype of result parameter for callback.

Define the datatype of the ADC conversion result parameter for callback functions. This should be defined according to the signedness and resolution of the conversions:

int16_t for signed, 12-bit
uint16_t for unsigned, 12-bit (the default type)
int8_t for signed, 8-bit
uint8_t for unsigned, 8-bit

Define this in conf_adc.h if the default datatype is not desired.

#define HOTTEMP offsetof(NVM_PROD_SIGNATURES_t, HOTTEMP)

Temperature at which TEMPSENSE1/TEMPSENSE0 is measured.

Referenced by adc_get_calibration_data().

#define ROOMTEMP offsetof(NVM_PROD_SIGNATURES_t, ROOMTEMP)

Temperature at which TEMPSENSE3/TEMPSENSE2 is measured.

Referenced by adc_get_calibration_data().

#define TEMPSENSE0 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE0)

Temperature sensor calibration byte 0.

Referenced by adc_get_calibration_data().

#define TEMPSENSE1 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE1)

Temperature sensor calibration byte 1.

Referenced by adc_get_calibration_data().

#define TEMPSENSE2 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE2)

Temperature sensor calibration byte 2.

Referenced by adc_get_calibration_data().

#define TEMPSENSE3 offsetof(NVM_PROD_SIGNATURES_t, TEMPSENSE3)

Temperature sensor calibration byte 3.

Referenced by adc_get_calibration_data().

typedef void(* adc_callback_t)(ADC_t *adc, uint8_t ch_mask, adc_result_t res)

ADC interrupt callback function pointer.

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (Only a single channel can be given in mask)
res	ADC conversion result.

typedef CONFIG_ADC_CALLBACK_TYPE adc_result_t

Datatype of ADC conversion result parameter for callback.

enum adc_calibration_data

ADC calibration data.

Enumerator
ADC_CAL_ADCA	ADC A pipeline calibration data.
ADC_CAL_ADCB	ADC B pipeline calibration data.
ADC_CAL_TEMPSENSE	Temperature sensor calibration data. Note 12-bit unsigned, measured at 85 degrees Celsius, equivalent to 358.15 kelvin. For AVR XMEGA E devices, the calibration reading is 12 Bit signed. AVR XMEGA E production signature row contains data for two calibration points. Each calibration point has one byte for storing the temperature at which the internal temperature sensor is measured and two bytes for the corresponding ADC reading.
ADC_CAL_HOTTEMP	Normally one calibration point is taken at 85 Deg C, but the exact value in Deg C is given in the HOTTEMP signature row.
ADC_CAL_TEMPSENSE2	ADC reading at ROOMTEMP in stored in TEMPSENSE2.
ADC_CAL_ROOMTEMP	The room temperature (in Deg C) measured during device manufacturing.

enum adc_current_limit

ADC current limit settings.

Enumerator
ADC_CURRENT_LIMIT_NO	No current limit.
ADC_CURRENT_LIMIT_LOW	Low current limit, max sampling rate 1.5 MSPS.
ADC_CURRENT_LIMIT_MED	Medium current limit, max sampling rate 1 MSPS.
ADC_CURRENT_LIMIT_HIGH	High current limit, max sampling rate 0.5 MSPS.

enum adc_gainstage_impmode

ADC gain stage impedance settings.

Enumerator
ADC_GAIN_HIGHIMPEDANCE	High impedance sources.
ADC_GAIN_LOWIMPEDANCE	Low impedance sources.

enum adc_reference

ADC reference settings.

Note: The choice in voltage reference varies between device families. Refer to the device manual for detailed information.

Enumerator
ADC_REF_BANDGAP	Internal 1 V from bandgap reference.
ADC_REF_VCC	VCC divided by 1.6.
ADC_REF_AREFA	External reference on AREFA pin.
ADC_REF_AREFB	External reference on AREFB pin.
ADC_REF_VCCDIV2	VCC divided by 2.

enum adc_resolution

ADC resolution settings.

Enumerator
ADC_RES_8	8-bit resolution, right-adjusted.
ADC_RES_12	12-bit resolution, right-adjusted.
ADC_RES_12_LEFT	12-bit resolution, left-adjusted.

enum adc_sign

ADC signedness settings.

Enumerator
ADC_SIGN_OFF	Unsigned conversions.
ADC_SIGN_ON	Signed conversions.

enum adc_trigger

ADC conversion trigger settings.

Note: The choice in conversion triggers varies between device families. Refer to the device manual for detailed information.

Enumerator
ADC_TRIG_MANUAL	Manually triggered conversions.
ADC_TRIG_FREERUN	Freerun mode conversion.
ADC_TRIG_EVENT_SINGLE	Event-triggered conversions on individual channels Pairs each event channel with an ADC channel. Note The maximum base event channel that can be used is determined by the number of channels to trigger conversions on.
ADC_TRIG_FREERUN_SWEEP	Freerunning conversion sweeps. Note These will start as soon as the ADC is enabled.
ADC_TRIG_EVENT_SWEEP	Event-triggered conversion sweeps. Note Only the base event channel is used in this mode.
ADC_TRIG_EVENT_SYNCSWEEP	Event-triggered, synchronized conversion sweeps. Note Only the base event channel is used in this mode.

static void adc_clear_interrupt_flag	(	ADC_t *	adc,
		uint8_t	ch_mask
	)

inlinestatic

Clear interrupt flag of ADC channel(s)

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (These can be OR'ed together.)

Note: The ADC must be enabled for this function to have any effect.

Referenced by adc_wait_for_interrupt_flag().

void adc_disable ( ADC_t * adc )

Disable ADC.

Disables the ADC and unlocks IDLE mode for the sleep manager.

Parameters

adc	Pointer to ADC module

References adc_disable_clock(), cpu_irq_restore(), cpu_irq_save(), SLEEPMGR_IDLE, and sleepmgr_unlock_mode().

Referenced by differential_signed_average(), and single_ended_unsigned_average().

static void adc_disable_internal_input	(	struct adc_config *	conf,
		uint8_t	int_inp
	)

inlinestatic

Disable internal ADC input.

Parameters

conf	Pointer to ADC module configuration.
int_inp	Internal input to disable: `ADC_INT_TEMPSENSE` for temperature sensor. `ADC_INT_BANDGAP` for bandgap reference.

References adc_config::refctrl.

void adc_enable ( ADC_t * adc )

Enable ADC.

Enables the ADC and locks IDLE mode for the sleep manager.

Parameters

adc	Pointer to ADC module

Note: To ensure accurate conversions, please wait for at least the specified start-up time between enabling the ADC module, and starting a conversion. For most XMEGA devices the start-up time is specified to be a maximum of 24 ADC clock cycles. Please verify the start-up time for the device in use.

References adc_enable_clock(), cpu_irq_restore(), cpu_irq_save(), SLEEPMGR_IDLE, and sleepmgr_lock_mode().

Referenced by differential_signed_average(), main(), and single_ended_unsigned_average().

static void adc_enable_internal_input	(	struct adc_config *	conf,
		uint8_t	int_inp
	)

inlinestatic

Enable internal ADC input.

Parameters

conf	Pointer to ADC module configuration.
int_inp	Internal input to enable: `ADC_INT_TEMPSENSE` for temperature sensor. `ADC_INT_BANDGAP` for bandgap reference.

References adc_config::refctrl.

Referenced by main().

static void adc_flush ( ADC_t * adc )

inlinestatic

Flush the ADC.

Forces the ADC to abort any ongoing conversions and restart its clock on the next peripheral clock cycle. Pending conversions are started after the clock reset.

Parameters

adc	Pointer to ADC module.

Note: The ADC must be enabled for this function to have any effect.

References cpu_irq_restore(), and cpu_irq_save().

static uint16_t adc_get_calibration_data ( enum adc_calibration_data cal )

inlinestatic

Get calibration data.

Parameters

cal	Identifier for calibration data to get.

References ADC_CAL_ADCA, ADC_CAL_ADCB, ADC_CAL_HOTTEMP, ADC_CAL_ROOMTEMP, ADC_CAL_TEMPSENSE, ADC_CAL_TEMPSENSE2, ADCACAL0, ADCACAL1, ADCBCAL0, ADCBCAL1, Assert, data, HOTTEMP, nvm_read_production_signature_row(), ROOMTEMP, TEMPSENSE0, TEMPSENSE1, TEMPSENSE2, and TEMPSENSE3.

Referenced by adc_write_configuration(), and main().

static __always_inline ADC_CH_t* adc_get_channel	(	ADC_t *	adc,
		uint8_t	ch_mask
	)

static

Get ADC channel pointer from channel mask.

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (Only a single channel can be given in mask)

Returns: Pointer to ADC channel

References ADC_NR_OF_CHANNELS, and Assert.

Referenced by adc_get_signed_result(), adc_get_unsigned_result(), adcch_read_configuration(), and adcch_write_configuration().

static uint8_t adc_get_interrupt_flag	(	ADC_t *	adc,
		uint8_t	ch_mask
	)

inlinestatic

Get interrupt flag of ADC channel(s)

Returns the interrupt flag of the masked channels. The meaning of the interrupt flag depends on what mode the individual channels are in.

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (These can be OR'ed together.)

Returns: Mask with interrupt flags.

Referenced by adc_wait_for_interrupt_flag().

static int16_t adc_get_signed_compare_value ( ADC_t * adc )

inlinestatic

Get signed compare value directly from ADC.

Gets the signed compare value directly from the ADC, with interrupt protection of the 16-bit read, for quick access while the ADC is enabled.

Parameters

adc	Pointer to ADC module.

References cpu_irq_restore(), and cpu_irq_save().

static int16_t adc_get_signed_result	(	ADC_t *	adc,
		uint8_t	ch_mask
	)

inlinestatic

Get signed result from ADC channel.

Returns the latest conversion result from the ADC channel as a signed type, with interrupt protection of the 16-bit read.

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (Only a single channel can be given in mask)

Returns: Latest conversion result of ADC channel, as signed 16-bit integer.

References adc_get_channel(), cpu_irq_restore(), and cpu_irq_save().

static uint16_t adc_get_unsigned_compare_value ( ADC_t * adc )

inlinestatic

Get unsigned compare value directly from ADC.

Gets the unsigned compare value directly from the ADC, with interrupt protection of the 16-bit read, for quick access while the ADC is enabled.

Parameters

adc	Pointer to ADC module.

References cpu_irq_restore(), and cpu_irq_save().

static uint16_t adc_get_unsigned_result	(	ADC_t *	adc,
		uint8_t	ch_mask
	)

inlinestatic

Get unsigned result from ADC channel.

Returns the latest conversion result from the ADC channel as an unsigned type, with interrupt protection of the 16-bit read.

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (Only a single channel can be given in mask)

Returns: Latest conversion result of ADC channel, as unsigned 16-bit integer.

References adc_get_channel(), cpu_irq_restore(), and cpu_irq_save().

bool adc_is_enabled ( ADC_t * adc )

Check if the ADC is enabled.

Parameters

adc	Pointer to ADC module.

Return values

true	if ADC is enabled.
false	if ADC is disabled.

References Assert.

void adc_read_configuration	(	ADC_t *	adc,
		struct adc_config *	conf
	)

Read configuration from ADC module.

Reads out the current configuration of the ADC module to the specified buffer.

Parameters

adc	Pointer to ADC module.
conf	Pointer to ADC module configuration.

References adc_disable_clock(), adc_enable_clock(), adc_config::cmp, cpu_irq_restore(), cpu_irq_save(), adc_config::ctrla, adc_config::ctrlb, adc_config::evctrl, adc_config::prescaler, and adc_config::refctrl.

Referenced by main(), run_differential_12bit_conversion_test(), run_differential_12bit_with_gain_conversion_test(), run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), run_single_channel_8bit_conversion_test(), run_single_ended_12bit_conversion_test(), and run_single_ended_8bit_conversion_test().

void adc_set_callback	(	ADC_t *	adc,
		adc_callback_t	callback
	)

Set ADC interrupt callback function.

Sets a new callback function for interrupts on the specified ADC.

Parameters

adc	Pointer to ADC module.
callback	Pointer to the callback function to set.

References Assert, cpu_irq_restore(), and cpu_irq_save().

Referenced by main().

static void adc_set_clock_rate	(	struct adc_config *	conf,
		uint32_t	clk_adc
	)

inlinestatic

Set ADC prescaler to get desired clock rate.

Sets the ADC prescaling so that its clock rate becomes at most clk_adc_hz. This is done by computing the ratio of the peripheral clock rate to the desired ADC clock rate, and rounding it upward to the nearest prescaling factor.

Parameters

conf	Pointer to ADC module configuration.
clk_adc	Desired ADC clock rate.

Note: The sample rate is not determined solely by the ADC clock rate for all devices. Setting the current limit mode on some devices will also affect the maximum ADC sampling rate. Refer to the device manual for detailed information on conversion timing and/or the current limitation mode.

References Assert, adc_config::prescaler, and sysclk_get_per_hz().

Referenced by main(), run_differential_12bit_conversion_test(), run_differential_12bit_with_gain_conversion_test(), run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), run_single_channel_8bit_conversion_test(), run_single_ended_12bit_conversion_test(), and run_single_ended_8bit_conversion_test().

static void adc_set_conversion_parameters	(	struct adc_config *	conf,
		enum adc_sign	sign,
		enum adc_resolution	res,
		enum adc_reference	ref
	)

inlinestatic

Set ADC conversion parameters.

Sets the signedness, resolution and voltage reference for conversions in the ADC module configuration.

Parameters

conf	Pointer to ADC module configuration.
sign	Conversion signedness.
res	Resolution of conversions.
ref	Voltage reference to use.

References adc_config::ctrlb, and adc_config::refctrl.

Referenced by main(), run_differential_12bit_conversion_test(), run_differential_12bit_with_gain_conversion_test(), run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), run_single_channel_8bit_conversion_test(), run_single_ended_12bit_conversion_test(), and run_single_ended_8bit_conversion_test().

static void adc_set_conversion_trigger	(	struct adc_config *	conf,
		enum adc_trigger	trig,
		uint8_t	nr_of_ch,
		uint8_t	base_ev_ch
	)

inlinestatic

Set ADC conversion trigger.

Configures the conversion triggering of the ADC.

For automatic triggering modes, the number of channels to start conversions on must be specified with nr_of_ch. The channel selection for these modes is incrementally inclusive, always starting with channel 0.

For event triggered modes, the base event channel must also be specified with base_ev_ch. The event channels are assigned to the ADC channels in an incremental fashion without wrap-around (in single-trigger event mode). This means that the maximum base event channel that can be used is determined by the number of ADC channels to start conversions on, i.e., nr_of_ch.

Parameters

conf	Pointer to ADC module configuration.
trig	Conversion trigger to set.
nr_of_ch	Number of ADC channels to trigger conversions on: `1` - `ADC_NR_OF_CHANNELS` (must be non-zero).
base_ev_ch	Base event channel, if used.

References ADC_EVACT_SYNCSWEEP_gc, ADC_NR_OF_CHANNELS, ADC_TRIG_EVENT_SINGLE, ADC_TRIG_EVENT_SWEEP, ADC_TRIG_EVENT_SYNCSWEEP, ADC_TRIG_FREERUN, ADC_TRIG_FREERUN_SWEEP, ADC_TRIG_MANUAL, Assert, adc_config::ctrlb, and adc_config::evctrl.

Referenced by main(), run_differential_12bit_conversion_test(), run_differential_12bit_with_gain_conversion_test(), run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), run_single_channel_8bit_conversion_test(), run_single_ended_12bit_conversion_test(), and run_single_ended_8bit_conversion_test().

static void adc_set_current_limit	(	struct adc_config *	conf,
		enum adc_current_limit	currlimit
	)

inlinestatic

Set ADC current limit.

Set the current limit mode for the ADC module. This setting affects the max sampling rate of the ADC.

Note: See the device datasheet and manual for detailed information about current consumption and sample rate limit.

Parameters

conf	Pointer to ADC module configuration.
currlimit	Current limit setting.

Note: Not all device families feature this setting.

References ADC_CURRENT_LIMIT_HIGH, ADC_CURRENT_LIMIT_LOW, ADC_CURRENT_LIMIT_MED, ADC_CURRENT_LIMIT_NO, ADC_CURRLIMIT_gm, ADC_CURRLIMIT_HIGH_gc, ADC_CURRLIMIT_LOW_gc, ADC_CURRLIMIT_MED_gc, ADC_CURRLIMIT_NO_gc, Assert, and adc_config::ctrlb.

static void adc_set_dma_request_group	(	struct adc_config *	conf,
		uint8_t	nr_of_ch
	)

inlinestatic

Set DMA request group.

Configures the DMA group request for the specified number of ADC channels. The channel group selection is incrementally inclusive, always starting with channel 0.

Parameters

conf	Pointer to ADC module configuration.
nr_of_ch	Number of channels for group request: 0 to disable. 2, 3 or 4 to enable.

Note: The number of channels in the DMA request group cannot be 1.; Not all device families feature this setting.

References ADC_NR_OF_CHANNELS, Assert, and adc_config::ctrla.

static void adc_set_gain_impedance_mode	(	struct adc_config *	conf,
		enum adc_gainstage_impmode	impmode
	)

inlinestatic

Set ADC gain stage impedance mode.

Parameters

conf	Pointer to ADC module configuration.
impmode	Gain stage impedance mode.

Note: Not all device families feature this setting.

References ADC_GAIN_HIGHIMPEDANCE, ADC_GAIN_LOWIMPEDANCE, Assert, and adc_config::ctrlb.

static void adc_start_conversion	(	ADC_t *	adc,
		uint8_t	ch_mask
	)

inlinestatic

Start one-shot conversion on ADC channel(s)

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (These can be OR'ed together.)

Note: The ADC must be enabled for this function to have any effect.

References cpu_irq_restore(), and cpu_irq_save().

Referenced by adc_handler(), differential_signed_average(), get_mean_sample_value(), ISR(), main(), and single_ended_unsigned_average().

static void adc_wait_for_interrupt_flag	(	ADC_t *	adc,
		uint8_t	ch_mask
	)

inlinestatic

Wait for interrupt flag of ADC channel(s)

Waits for the interrupt flag of the specified channel(s) to be set, then clears it before returning. If several channels are masked, the function will wait for all interrupt flags to be set.

Parameters

adc	Pointer to ADC module.
ch_mask	Mask of ADC channel(s): `ADC_CHn` , where `n` specifies the channel. (These can be OR'ed together.)

References adc_clear_interrupt_flag(), and adc_get_interrupt_flag().

Referenced by differential_signed_average(), get_mean_sample_value(), main(), and single_ended_unsigned_average().

void adc_write_configuration	(	ADC_t *	adc,
		const struct adc_config *	conf
	)

Write configuration to ADC module.

Disables the ADC and flushes its pipeline before writing the specified configuration and factory calibration value to it. If the ADC was enabled upon entry of the function, it is enabled upon function return.

Parameters

adc	Pointer to ADC module.
conf	Pointer to ADC module configuration.

References ADC_CAL_ADCA, ADC_CAL_ADCB, adc_disable_clock(), adc_enable_clock(), adc_get_calibration_data(), Assert, adc_config::cmp, cpu_irq_restore(), cpu_irq_save(), adc_config::ctrla, adc_config::ctrlb, adc_config::evctrl, adc_config::prescaler, and adc_config::refctrl.

Referenced by main(), run_differential_12bit_conversion_test(), run_differential_12bit_with_gain_conversion_test(), run_dual_channel_12bit_conversion_test(), run_dual_channel_8bit_conversion_test(), run_single_channel_12bit_conversion_test(), run_single_channel_8bit_conversion_test(), run_single_ended_12bit_conversion_test(), and run_single_ended_8bit_conversion_test().

Microchip® Advanced Software Framework

Data Structures

Macros

Enumerations

Calibration data addresses

ADC channel masks

Internal ADC input masks

Internal functions for driver

ADC interrupt callback function

ADC module management

ADC module configuration