DAC - Digital to Analog Converter#

Digital to Analog Converter (DAC) Peripheral API.

This module contains functions to control the DAC peripheral of Silicon Labs 32-bit MCUs and SoCs. The DAC converts digital values to analog signals at up to 500 ksps with 12-bit accuracy. The DAC is designed for low-energy consumption and can also provide very good performance.

Modules#

DAC_Init_TypeDef

DAC_InitChannel_TypeDef

Enumerations#

enum

DAC_ConvMode_TypeDef {

dacConvModeContinuous = _DAC_CTRL_CONVMODE_CONTINUOUS

dacConvModeSampleHold = _DAC_CTRL_CONVMODE_SAMPLEHOLD

dacConvModeSampleOff = _DAC_CTRL_CONVMODE_SAMPLEOFF

}

Conversion mode.

enum

DAC_Output_TypeDef {

dacOutputDisable = _DAC_CTRL_OUTMODE_DISABLE

dacOutputPin = _DAC_CTRL_OUTMODE_PIN

dacOutputADC = _DAC_CTRL_OUTMODE_ADC

dacOutputPinADC = _DAC_CTRL_OUTMODE_PINADC

}

Output mode.

enum

DAC_PRSSEL_TypeDef {

dacPRSSELCh0 = _DAC_CH0CTRL_PRSSEL_PRSCH0

dacPRSSELCh1 = _DAC_CH0CTRL_PRSSEL_PRSCH1

dacPRSSELCh2 = _DAC_CH0CTRL_PRSSEL_PRSCH2

dacPRSSELCh3 = _DAC_CH0CTRL_PRSSEL_PRSCH3

dacPRSSELCh4 = _DAC_CH0CTRL_PRSSEL_PRSCH4

dacPRSSELCh5 = _DAC_CH0CTRL_PRSSEL_PRSCH5

dacPRSSELCh6 = _DAC_CH0CTRL_PRSSEL_PRSCH6

dacPRSSELCh7 = _DAC_CH0CTRL_PRSSEL_PRSCH7

dacPRSSELCh8 = _DAC_CH0CTRL_PRSSEL_PRSCH8

dacPRSSELCh9 = _DAC_CH0CTRL_PRSSEL_PRSCH9

dacPRSSELCh10 = _DAC_CH0CTRL_PRSSEL_PRSCH10

dacPRSSELCh11 = _DAC_CH0CTRL_PRSSEL_PRSCH11

}

Peripheral Reflex System signal used to trigger single sample.

enum

DAC_Ref_TypeDef {

dacRef1V25 = _DAC_CTRL_REFSEL_1V25

dacRef2V5 = _DAC_CTRL_REFSEL_2V5

dacRefVDD = _DAC_CTRL_REFSEL_VDD

}

Reference voltage for DAC.

enum

DAC_Refresh_TypeDef {

dacRefresh8 = _DAC_CTRL_REFRSEL_8CYCLES

dacRefresh16 = _DAC_CTRL_REFRSEL_16CYCLES

dacRefresh32 = _DAC_CTRL_REFRSEL_32CYCLES

dacRefresh64 = _DAC_CTRL_REFRSEL_64CYCLES

}

Refresh interval.

Functions#

void

DAC_Enable(DAC_TypeDef *dac, unsigned int ch, bool enable)

Enable/disable the DAC channel.

void

DAC_Init(DAC_TypeDef *dac, const DAC_Init_TypeDef *init)

Initialize DAC.

void

DAC_InitChannel(DAC_TypeDef *dac, const DAC_InitChannel_TypeDef *init, unsigned int ch)

Initialize DAC channel.

void

DAC_ChannelOutputSet(DAC_TypeDef *dac, unsigned int channel, uint32_t value)

Set the output signal of a DAC channel to a given value.

uint8_t

DAC_PrescaleCalc(uint32_t dacFreq, uint32_t hfperFreq)

Calculate prescaler value used to determine the DAC clock.

void

DAC_Reset(DAC_TypeDef *dac)

Reset DAC to the same state that it was in after a hardware reset.

void

DAC_Channel0OutputSet(DAC_TypeDef *dac, uint32_t value)

Set the output signal of DAC channel 0 to a given value.

void

DAC_Channel1OutputSet(DAC_TypeDef *dac, uint32_t value)

Set the output signal of DAC channel 1 to a given value.

void

DAC_IntClear(DAC_TypeDef *dac, uint32_t flags)

Clear one or more pending DAC interrupts.

void

DAC_IntDisable(DAC_TypeDef *dac, uint32_t flags)

Disable one or more DAC interrupts.

void

DAC_IntEnable(DAC_TypeDef *dac, uint32_t flags)

Enable one or more DAC interrupts.

uint32_t

DAC_IntGet(DAC_TypeDef *dac)

Get pending DAC interrupt flags.

uint32_t

DAC_IntGetEnabled(DAC_TypeDef *dac)

Get enabled and pending DAC interrupt flags.

void

DAC_IntSet(DAC_TypeDef *dac, uint32_t flags)

Set one or more pending DAC interrupts from SW.

Macros#

#define

DAC_INIT_DEFAULT undefined

Default configuration for DAC initialization structure.

#define

DAC_INITCHANNEL_DEFAULT undefined

Default configuration for DAC channel initialization structure.

Enumeration Documentation#

DAC_ConvMode_TypeDef#

DAC_ConvMode_TypeDef

Conversion mode.

Enumerator
dacConvModeContinuous	Continuous mode.
dacConvModeSampleHold	Sample/hold mode.
dacConvModeSampleOff	Sample/shut off mode.

DAC_Output_TypeDef#

DAC_Output_TypeDef

Output mode.

Enumerator
dacOutputDisable	Output to pin and ADC disabled.
dacOutputPin	Output to pin only.
dacOutputADC	Output to ADC only.
dacOutputPinADC	Output to pin and ADC.

DAC_PRSSEL_TypeDef#

DAC_PRSSEL_TypeDef

Peripheral Reflex System signal used to trigger single sample.

Enumerator
dacPRSSELCh0	PRS channel 0.
dacPRSSELCh1	PRS channel 1.
dacPRSSELCh2	PRS channel 2.
dacPRSSELCh3	PRS channel 3.
dacPRSSELCh4	PRS channel 4.
dacPRSSELCh5	PRS channel 5.
dacPRSSELCh6	PRS channel 6.
dacPRSSELCh7	PRS channel 7.
dacPRSSELCh8	PRS channel 8.
dacPRSSELCh9	PRS channel 9.
dacPRSSELCh10	PRS channel 10.
dacPRSSELCh11	PRS channel 11.

DAC_Ref_TypeDef#

DAC_Ref_TypeDef

Reference voltage for DAC.

Enumerator
dacRef1V25	Internal 1.25V bandgap reference.
dacRef2V5	Internal 2.5V bandgap reference.
dacRefVDD	VDD reference.

DAC_Refresh_TypeDef#

DAC_Refresh_TypeDef

Refresh interval.

Enumerator
dacRefresh8	Refresh every 8 prescaled cycles.
dacRefresh16	Refresh every 16 prescaled cycles.
dacRefresh32	Refresh every 32 prescaled cycles.
dacRefresh64	Refresh every 64 prescaled cycles.

Function Documentation#

DAC_Enable#

void DAC_Enable (DAC_TypeDef * dac, unsigned int ch, bool enable)

Enable/disable the DAC channel.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	A pointer to the DAC peripheral register block.
unsigned int	[in]	ch	A channel to enable/disable.
bool	[in]	enable	true to enable DAC channel, false to disable.

DAC_Init#

void DAC_Init (DAC_TypeDef * dac, const DAC_Init_TypeDef * init)

Initialize DAC.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	A pointer to the DAC peripheral register block.
const DAC_Init_TypeDef *	[in]	init	A pointer to the DAC initialization structure.

Initializes common parts for both channels. In addition, channel control configuration must be done. See DAC_InitChannel().

Note

This function will disable both channels prior to configuration.

DAC_InitChannel#

void DAC_InitChannel (DAC_TypeDef * dac, const DAC_InitChannel_TypeDef * init, unsigned int ch)

Initialize DAC channel.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	A pointer to the DAC peripheral register block.
const DAC_InitChannel_TypeDef *	[in]	init	A pointer to the DAC initialization structure.
unsigned int	[in]	ch	A channel number to initialize.

DAC_ChannelOutputSet#

void DAC_ChannelOutputSet (DAC_TypeDef * dac, unsigned int channel, uint32_t value)

Set the output signal of a DAC channel to a given value.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	A pointer to the DAC peripheral register block.
unsigned int	[in]	channel	A channel number to set the output.
uint32_t	[in]	value	A value to write to the channel output register CHnDATA.

This function sets the output signal of a DAC channel by writing value to the corresponding CHnDATA register.

DAC_PrescaleCalc#

uint8_t DAC_PrescaleCalc (uint32_t dacFreq, uint32_t hfperFreq)

Calculate prescaler value used to determine the DAC clock.

Parameters

Type	Direction	Argument Name	Description
uint32_t	[in]	dacFreq	DAC frequency wanted. The frequency will automatically be adjusted to be below the maximum allowed DAC clock.
uint32_t	[in]	hfperFreq	Frequency in Hz of the reference HFPER clock. Set to 0 to use the currently defined HFPER clock setting.

The DAC clock is given by: HFPERCLK / (prescale ^ 2). If the requested DAC frequency is low and the maximum prescaler value can't adjust the actual DAC frequency lower than the requested DAC frequency, the maximum prescaler value is returned resulting in a higher DAC frequency than requested.

Returns

Prescaler value to use for DAC to achieve a clock value <= dacFreq.

DAC_Reset#

void DAC_Reset (DAC_TypeDef * dac)

Reset DAC to the same state that it was in after a hardware reset.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	A pointer to the ADC peripheral register block.

DAC_Channel0OutputSet#

void DAC_Channel0OutputSet (DAC_TypeDef * dac, uint32_t value)

Set the output signal of DAC channel 0 to a given value.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.
uint32_t	[in]	value	Value to write to the channel 0 output register CH0DATA.

This function sets the output signal of DAC channel 0 by writing value to the CH0DATA register.

DAC_Channel1OutputSet#

void DAC_Channel1OutputSet (DAC_TypeDef * dac, uint32_t value)

Set the output signal of DAC channel 1 to a given value.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.
uint32_t	[in]	value	Value to write to the channel 1 output register CH1DATA.

Sets the output signal of DAC channel 1 by writing value to the CH1DATA register.

DAC_IntClear#

void DAC_IntClear (DAC_TypeDef * dac, uint32_t flags)

Clear one or more pending DAC interrupts.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.
uint32_t	[in]	flags	Pending DAC interrupt source to clear. Use a bitwise logic OR combination of valid interrupt flags for the DAC module (DAC_IF_nnn).

DAC_IntDisable#

void DAC_IntDisable (DAC_TypeDef * dac, uint32_t flags)

Disable one or more DAC interrupts.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.
uint32_t	[in]	flags	DAC interrupt sources to disable. Use a bitwise logic OR combination of valid interrupt flags for the DAC module (DAC_IF_nnn).

DAC_IntEnable#

void DAC_IntEnable (DAC_TypeDef * dac, uint32_t flags)

Enable one or more DAC interrupts.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.
uint32_t	[in]	flags	DAC interrupt sources to enable. Use a bitwise logic OR combination of valid interrupt flags for the DAC module (DAC_IF_nnn).

Note

Depending on the use, a pending interrupt may already be set prior to enabling the interrupt. To ignore a pending interrupt, consider using DAC_IntClear() prior to enabling the interrupt.

DAC_IntGet#

uint32_t DAC_IntGet (DAC_TypeDef * dac)

Get pending DAC interrupt flags.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.

Note

Event bits are not cleared by the use of this function.

Returns

DAC interrupt sources pending. A bitwise logic OR combination of valid interrupt flags for the DAC module (DAC_IF_nnn).

DAC_IntGetEnabled#

uint32_t DAC_IntGetEnabled (DAC_TypeDef * dac)

Get enabled and pending DAC interrupt flags.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.

Useful for handling more interrupt sources in the same interrupt handler.

Note

Interrupt flags are not cleared by the use of this function.

Returns

Pending and enabled DAC interrupt sources. Return value is the bitwise AND combination of
- the OR combination of enabled interrupt sources in DACx_IEN_nnn register (DACx_IEN_nnn) and
- the OR combination of valid interrupt flags of the DAC module (DACx_IF_nnn).

DAC_IntSet#

void DAC_IntSet (DAC_TypeDef * dac, uint32_t flags)

Set one or more pending DAC interrupts from SW.

Parameters

Type	Direction	Argument Name	Description
DAC_TypeDef *	[in]	dac	Pointer to DAC peripheral register block.
uint32_t	[in]	flags	DAC interrupt sources to set to pending. Use a bitwise logic OR combination of valid interrupt flags for the DAC module (DAC_IF_nnn).