LESENSE - Low Energy Sensor

Description

Low Energy Sensor (LESENSE) Peripheral API.

This module contains functions to control the LESENSE peripheral of Silicon Labs 32-bit MCUs and SoCs. LESENSE is a low-energy sensor interface capable of autonomously collecting and processing data from multiple sensors even when in EM2.

Data Structures

struct  LESENSE_CoreCtrlDesc_TypeDef
 Core control (LESENSE_CTRL/CFG) descriptor structure.
 
struct  LESENSE_TimeCtrlDesc_TypeDef
 LESENSE timing control descriptor structure.
 
struct  LESENSE_PerCtrlDesc_TypeDef
 LESENSE peripheral control descriptor structure.
 
struct  LESENSE_DecCtrlDesc_TypeDef
 LESENSE decoder control descriptor structure.
 
struct  LESENSE_Init_TypeDef
 LESENSE module initialization structure.
 
struct  LESENSE_ChDesc_TypeDef
 Channel descriptor structure.
 
struct  LESENSE_ChAll_TypeDef
 Configuration structure for all the scan channels.
 
struct  LESENSE_AltExDesc_TypeDef
 Alternate excitation descriptor structure.
 
struct  LESENSE_ConfAltEx_TypeDef
 Configuration structure for the alternate excitation.
 
struct  LESENSE_DecStCond_TypeDef
 Decoder state condition descriptor structure.
 
struct  LESENSE_DecStDesc_TypeDef
 Decoder state x configuration structure.
 
struct  LESENSE_DecStAll_TypeDef
 Configuration structure for decoder.
 

Functions

void LESENSE_Init (const LESENSE_Init_TypeDef *init, bool reqReset)
 Initialize the LESENSE module.
 
uint32_t LESENSE_ScanFreqSet (uint32_t refFreq, uint32_t scanFreq)
 Set the scan frequency for periodic scanning.
 
void LESENSE_ScanModeSet (LESENSE_ScanMode_TypeDef scanMode, bool start)
 Set scan mode of the LESENSE channels.
 
void LESENSE_StartDelaySet (uint8_t startDelay)
 Set the start delay of the sensor interaction on each channel.
 
void LESENSE_ClkDivSet (LESENSE_ChClk_TypeDef clk, LESENSE_ClkPresc_TypeDef clkDiv)
 Set the clock division for LESENSE timers.
 
void LESENSE_ChannelAllConfig (const LESENSE_ChAll_TypeDef *confChAll)
 Configure all (16) LESENSE sensor channels.
 
void LESENSE_ChannelConfig (const LESENSE_ChDesc_TypeDef *confCh, uint32_t chIdx)
 Configure a single LESENSE sensor channel.
 
void LESENSE_AltExConfig (const LESENSE_ConfAltEx_TypeDef *confAltEx)
 Configure the LESENSE alternate excitation modes.
 
void LESENSE_ChannelEnable (uint8_t chIdx, bool enaScanCh, bool enaPin)
 Enable/disable LESENSE scan channel and the pin assigned to it.
 
void LESENSE_ChannelEnableMask (uint16_t chMask, uint16_t pinMask)
 Enable/disable LESENSE scan channel and the pin assigned to it.
 
void LESENSE_ChannelTimingSet (uint8_t chIdx, uint8_t exTime, uint8_t sampleDelay, uint16_t measDelay)
 Set LESENSE channel timing parameters.
 
void LESENSE_ChannelThresSet (uint8_t chIdx, uint16_t acmpThres, uint16_t cntThres)
 Set LESENSE channel threshold parameters.
 
void LESENSE_ChannelSlidingWindow (uint8_t chIdx, uint32_t windowSize, uint32_t initValue)
 Configure a Sliding Window evaluation mode for a specific channel.
 
void LESENSE_ChannelStepDetection (uint8_t chIdx, uint32_t stepSize, uint32_t initValue)
 Configure the step detection evaluation mode for a specific channel.
 
void LESENSE_WindowSizeSet (uint32_t windowSize)
 Set the window size for all LESENSE channels.
 
void LESENSE_StepSizeSet (uint32_t stepSize)
 Set the step size for all LESENSE channels.
 
void LESENSE_DecoderStateAllConfig (const LESENSE_DecStAll_TypeDef *confDecStAll)
 Configure all LESENSE decoder states.
 
void LESENSE_DecoderStateConfig (const LESENSE_DecStDesc_TypeDef *confDecSt, uint32_t decSt)
 Configure a single LESENSE decoder state.
 
void LESENSE_DecoderStateSet (uint32_t decSt)
 Set the LESENSE decoder state.
 
uint32_t LESENSE_DecoderStateGet (void)
 Get the current state of the LESENSE decoder.
 
void LESENSE_DecoderPrsOut (bool enable, uint32_t decMask, uint32_t decVal)
 Enable or disable the PRS output from the LESENSE decoder.
 
void LESENSE_ScanStart (void)
 Start scanning sensors.
 
void LESENSE_ScanStop (void)
 Stop scanning sensors.
 
void LESENSE_DecoderStart (void)
 Start the LESENSE decoder.
 
void LESENSE_ResultBufferClear (void)
 Clear the result buffer.
 
void LESENSE_Reset (void)
 Reset the LESENSE module.
 
void LESENSE_DecoderStop (void)
 Stop LESENSE decoder.
 
uint32_t LESENSE_StatusGet (void)
 Get the current status of LESENSE.
 
void LESENSE_StatusWait (uint32_t flag)
 Wait until status of LESENSE is equal to what was requested.
 
uint32_t LESENSE_ChannelActiveGet (void)
 Get the currently active channel index.
 
uint32_t LESENSE_ScanResultGet (void)
 Get the latest scan comparison result (1 bit / channel).
 
uint32_t LESENSE_ScanResultDataGet (void)
 Get the oldest unread data from the result buffer.
 
uint32_t LESENSE_ScanResultDataBufferGet (uint32_t idx)
 Get data from the result data buffer.
 
uint32_t LESENSE_SensorStateGet (void)
 Get the current state of the LESENSE sensor.
 
void LESENSE_IntClear (uint32_t flags)
 Clear one or more pending LESENSE interrupts.
 
void LESENSE_IntEnable (uint32_t flags)
 Enable one or more LESENSE interrupts.
 
void LESENSE_IntDisable (uint32_t flags)
 Disable one or more LESENSE interrupts.
 
void LESENSE_IntSet (uint32_t flags)
 Set one or more pending LESENSE interrupts from SW.
 
uint32_t LESENSE_IntGet (void)
 Get pending LESENSE interrupt flags.
 
uint32_t LESENSE_IntGetEnabled (void)
 Get enabled and pending LESENSE interrupt flags.
 

Macros

#define LESENSE_NUM_DECODER_STATES   (_LESENSE_DECSTATE_DECSTATE_MASK + 1)
 Number of decoder states supported by current device.
 
#define LESENSE_NUM_CHANNELS   16
 Number of LESENSE channels.
 
#define LESENSE_CORECTRL_DESC_DEFAULT
 Default configuration for LESENSE_CtrlDesc_TypeDef structure.
 
#define LESENSE_TIMECTRL_DESC_DEFAULT
 Default configuration for LESENSE_TimeCtrlDesc_TypeDef structure.
 
#define LESENSE_PERCTRL_DESC_DEFAULT
 Default configuration for LESENSE_PerCtrl_TypeDef structure.
 
#define LESENSE_DECCTRL_DESC_DEFAULT
 Default configuration for LESENSE_PerCtrl_TypeDef structure.
 
#define LESENSE_INIT_DEFAULT
 Default configuration for LESENSE_Init_TypeDef structure.
 
#define LESENSE_CH_CONF_DEFAULT
 Default configuration for the scan channel.
 
#define LESENSE_SCAN_CONF_DEFAULT
 Default configuration for all the sensor channels.
 
#define LESENSE_ALTEX_CH_CONF_DEFAULT
 Default configuration for the alternate excitation channel.
 
#define LESENSE_ALTEX_CONF_DEFAULT
 Default configuration for all the alternate excitation channels.
 
#define LESENSE_ST_CONF_DEFAULT
 Default configuration for the decoder state condition.
 
#define LESENSE_DECODER_CONF_DEFAULT
 Default configuration for all decoder states.
 

Enumerations

enum  LESENSE_ClkPresc_TypeDef {
  lesenseClkDiv_1 = 0,
  lesenseClkDiv_2 = 1,
  lesenseClkDiv_4 = 2,
  lesenseClkDiv_8 = 3,
  lesenseClkDiv_16 = 4,
  lesenseClkDiv_32 = 5,
  lesenseClkDiv_64 = 6,
  lesenseClkDiv_128 = 7
}
 Clock divisors for controlling the prescaling factor of the period counter.
 
enum  LESENSE_ScanMode_TypeDef {
  lesenseScanStartPeriodic = LESENSE_CTRL_SCANMODE_PERIODIC,
  lesenseScanStartOneShot = LESENSE_CTRL_SCANMODE_ONESHOT,
  lesenseScanStartPRS = LESENSE_CTRL_SCANMODE_PRS
}
 Scan modes.
 
enum  LESENSE_PRSSel_TypeDef {
  lesensePRSCh0 = 0,
  lesensePRSCh1 = 1,
  lesensePRSCh2 = 2,
  lesensePRSCh3 = 3,
  lesensePRSCh4 = 4,
  lesensePRSCh5 = 5,
  lesensePRSCh6 = 6,
  lesensePRSCh7 = 7,
  lesensePRSCh8 = 8,
  lesensePRSCh9 = 9,
  lesensePRSCh10 = 10,
  lesensePRSCh11 = 11
}
 PRS sources.
 
enum  LESENSE_AltExMap_TypeDef {
  lesenseAltExMapALTEX = _LESENSE_CTRL_ALTEXMAP_ALTEX,
  lesenseAltExMapCH = _LESENSE_CTRL_ALTEXMAP_CH
}
 Locations of the alternate excitation function.
 
enum  LESENSE_BufTrigLevel_TypeDef {
  lesenseBufTrigHalf = LESENSE_CTRL_BUFIDL_HALFFULL,
  lesenseBufTrigFull = LESENSE_CTRL_BUFIDL_FULL
}
 Result buffer interrupt and DMA trigger levels.
 
enum  LESENSE_DMAWakeUp_TypeDef {
  lesenseDMAWakeUpDisable = LESENSE_CTRL_DMAWU_DISABLE,
  lesenseDMAWakeUpBufValid = LESENSE_CTRL_DMAWU_BUFDATAV,
  lesenseDMAWakeUpBufLevel = LESENSE_CTRL_DMAWU_BUFLEVEL
}
 Modes of operation for DMA wakeup from EM2.
 
enum  LESENSE_BiasMode_TypeDef {
  lesenseBiasModeDutyCycle = LESENSE_BIASCTRL_BIASMODE_DUTYCYCLE,
  lesenseBiasModeHighAcc = LESENSE_BIASCTRL_BIASMODE_HIGHACC,
  lesenseBiasModeDontTouch = LESENSE_BIASCTRL_BIASMODE_DONTTOUCH
}
 Bias modes.
 
enum  LESENSE_ScanConfSel_TypeDef {
  lesenseScanConfDirMap = LESENSE_CTRL_SCANCONF_DIRMAP,
  lesenseScanConfInvMap = LESENSE_CTRL_SCANCONF_INVMAP,
  lesenseScanConfToggle = LESENSE_CTRL_SCANCONF_TOGGLE,
  lesenseScanConfDecDef = LESENSE_CTRL_SCANCONF_DECDEF
}
 Scan configuration.
 
enum  LESENSE_ControlDACData_TypeDef {
  lesenseDACIfData = _LESENSE_PERCTRL_DACCH0DATA_DACDATA,
  lesenseThres = _LESENSE_PERCTRL_DACCH0DATA_THRES
}
 DAC CHx data control configuration.
 
enum  LESENSE_ControlACMP_TypeDef {
  lesenseACMPModeDisable = _LESENSE_PERCTRL_ACMP0MODE_DISABLE,
  lesenseACMPModeMux = _LESENSE_PERCTRL_ACMP0MODE_MUX,
  lesenseACMPModeMuxThres = _LESENSE_PERCTRL_ACMP0MODE_MUXTHRES
}
 ACMPx control configuration.
 
enum  LESENSE_WarmupMode_TypeDef {
  lesenseWarmupModeNormal = LESENSE_PERCTRL_WARMUPMODE_NORMAL,
  lesenseWarmupModeACMP = LESENSE_PERCTRL_WARMUPMODE_KEEPACMPWARM,
  lesenseWarmupModeDAC = LESENSE_PERCTRL_WARMUPMODE_KEEPDACWARM,
  lesenseWarmupModeKeepWarm = LESENSE_PERCTRL_WARMUPMODE_KEEPACMPDACWARM
}
 Warm up modes.
 
enum  LESENSE_DecInput_TypeDef {
  lesenseDecInputSensorSt = LESENSE_DECCTRL_INPUT_SENSORSTATE,
  lesenseDecInputPRS = LESENSE_DECCTRL_INPUT_PRS
}
 Decoder input source configuration.
 
enum  LESENSE_ChSampleMode_TypeDef {
  lesenseSampleModeCounter = 0x0 << _LESENSE_CH_INTERACT_SAMPLE_SHIFT,
  lesenseSampleModeACMP = LESENSE_CH_INTERACT_SAMPLE_ACMP,
  lesenseSampleModeADC = LESENSE_CH_INTERACT_SAMPLE_ADC,
  lesenseSampleModeADCDiff = LESENSE_CH_INTERACT_SAMPLE_ADCDIFF
}
 Compare source selection for sensor sampling.
 
enum  LESENSE_ChIntMode_TypeDef {
  lesenseSetIntNone = LESENSE_CH_INTERACT_SETIF_NONE,
  lesenseSetIntLevel = LESENSE_CH_INTERACT_SETIF_LEVEL,
  lesenseSetIntPosEdge = LESENSE_CH_INTERACT_SETIF_POSEDGE,
  lesenseSetIntNegEdge = LESENSE_CH_INTERACT_SETIF_NEGEDGE,
  lesenseSetIntBothEdges = LESENSE_CH_INTERACT_SETIF_BOTHEDGES
}
 Interrupt generation setup for CHx interrupt flag.
 
enum  LESENSE_ChPinExMode_TypeDef {
  lesenseChPinExDis = LESENSE_CH_INTERACT_EXMODE_DISABLE,
  lesenseChPinExHigh = LESENSE_CH_INTERACT_EXMODE_HIGH,
  lesenseChPinExLow = LESENSE_CH_INTERACT_EXMODE_LOW,
  lesenseChPinExDACOut = LESENSE_CH_INTERACT_EXMODE_DACOUT
}
 Channel pin mode for the excitation phase of the scan sequence.
 
enum  LESENSE_ChPinIdleMode_TypeDef {
  lesenseChPinIdleDis = _LESENSE_IDLECONF_CH0_DISABLE,
  lesenseChPinIdleHigh = _LESENSE_IDLECONF_CH0_HIGH,
  lesenseChPinIdleLow = _LESENSE_IDLECONF_CH0_LOW,
  lesenseChPinIdleDACC = _LESENSE_IDLECONF_CH0_DAC
}
 Channel pin mode for the idle phase of scan sequence.
 
enum  LESENSE_ChClk_TypeDef {
  lesenseClkLF = _LESENSE_CH_INTERACT_EXCLK_LFACLK,
  lesenseClkHF = _LESENSE_CH_INTERACT_EXCLK_AUXHFRCO
}
 Clock used for excitation and sample delay timing.
 
enum  LESENSE_ChCompMode_TypeDef {
  lesenseCompModeLess = LESENSE_CH_EVAL_COMP_LESS,
  lesenseCompModeGreaterOrEq = LESENSE_CH_EVAL_COMP_GE
}
 Compare modes for counter comparison.
 
enum  LESENSE_ChEvalMode_TypeDef {
  lesenseEvalModeThreshold = _LESENSE_CH_EVAL_MODE_THRES,
  lesenseEvalModeSlidingWindow = _LESENSE_CH_EVAL_MODE_SLIDINGWIN,
  lesenseEvalModeStepDetection = _LESENSE_CH_EVAL_MODE_STEPDET
}
 Sensor evaluation modes.
 
enum  LESENSE_AltExPinIdle_TypeDef {
  lesenseAltExPinIdleDis = _LESENSE_ALTEXCONF_IDLECONF0_DISABLE,
  lesenseAltExPinIdleHigh = _LESENSE_ALTEXCONF_IDLECONF0_HIGH,
  lesenseAltExPinIdleLow = _LESENSE_ALTEXCONF_IDLECONF0_LOW
}
 Idle phase configuration of the alternate excitation channels.
 
enum  LESENSE_StTransAct_TypeDef {
  lesenseTransActNone = LESENSE_ST_TCONFA_PRSACT_NONE,
  lesenseTransActPRS0 = LESENSE_ST_TCONFA_PRSACT_PRS0,
  lesenseTransActPRS1 = LESENSE_ST_TCONFA_PRSACT_PRS1,
  lesenseTransActPRS01 = LESENSE_ST_TCONFA_PRSACT_PRS01,
  lesenseTransActPRS2 = LESENSE_ST_TCONFA_PRSACT_PRS2,
  lesenseTransActPRS02 = LESENSE_ST_TCONFA_PRSACT_PRS02,
  lesenseTransActPRS12 = LESENSE_ST_TCONFA_PRSACT_PRS12,
  lesenseTransActPRS012 = LESENSE_ST_TCONFA_PRSACT_PRS012,
  lesenseTransActUp = LESENSE_ST_TCONFA_PRSACT_UP,
  lesenseTransActDown = LESENSE_ST_TCONFA_PRSACT_DOWN,
  lesenseTransActUpAndPRS2 = LESENSE_ST_TCONFA_PRSACT_UPANDPRS2,
  lesenseTransActDownAndPRS2 = LESENSE_ST_TCONFA_PRSACT_DOWNANDPRS2
}
 Transition action modes.
 

Function Documentation

◆ LESENSE_Init()

void LESENSE_Init ( const LESENSE_Init_TypeDef init,
bool  reqReset 
)

Initialize the LESENSE module.

This function configures the main parameters of the LESENSE interface. See the initialization parameter type definition (LESENSE_Init_TypeDef) for more details.

Note
LESENSE_Init() is designed to initialize LESENSE once in an operation cycle. Be aware of the effects of reconfiguration if using this function from multiple sources in your code. This function has not been designed to be re-entrant. Requesting reset by setting reqReset to true is required in each reset or power-on cycle to configure the default values of the RAM mapped LESENSE registers. Notice that GPIO pins used by the LESENSE module must be properly configured by the user explicitly for the LESENSE to work as intended. (When configuring pins, one should remember to consider the sequence of configuration to avoid unintended pulses/glitches on output pins.)
Parameters
[in]initThe LESENSE initialization structure.
[in]reqResetRequest to call LESENSE_Reset() first to initialize all LESENSE registers with default values.

◆ LESENSE_ScanFreqSet()

uint32_t LESENSE_ScanFreqSet ( uint32_t  refFreq,
uint32_t  scanFreq 
)

Set the scan frequency for periodic scanning.

This function only applies to LESENSE if a period counter is used as a trigger for scan start. The calculation is based on the following formula: Fscan = LFACLKles / ((1+PCTOP)*2^PCPRESC)

Note
Note that the calculation does not necessarily result in the requested scan frequency due to integer division. Check the return value for the resulted scan frequency.
Parameters
[in]refFreqSelect reference LFACLK clock frequency in Hz. If set to 0, the current clock frequency is being used as a reference.
[in]scanFreqSet the desired scan frequency in Hz.
Returns
Frequency in Hz calculated and set by this function. Users can use this to compare the requested and set values.

◆ LESENSE_ScanModeSet()

void LESENSE_ScanModeSet ( LESENSE_ScanMode_TypeDef  scanMode,
bool  start 
)

Set scan mode of the LESENSE channels.

This function configures how the scan start is triggered. It can be used for re-configuring the scan mode while running the application but it is also used by LESENSE_Init() for initialization.

Note
Users can configure the scan mode by LESENSE