Sensor

Files
file	sensor.h

Data Structures
struct	ASensorVector
struct	AMetaDataEvent
struct	AUncalibratedEvent
struct	AHeartRateEvent
struct	ASensorEvent

Macros
#define	ASENSOR_STANDARD_GRAVITY   (9.80665f)
#define	ASENSOR_MAGNETIC_FIELD_EARTH_MAX   (60.0f)
#define	ASENSOR_MAGNETIC_FIELD_EARTH_MIN   (30.0f)

Typedefs
typedef struct ASensorVector	ASensorVector
typedef struct AMetaDataEvent	AMetaDataEvent
typedef struct AUncalibratedEvent	AUncalibratedEvent
typedef struct AHeartRateEvent	AHeartRateEvent
typedef struct ASensorEvent	ASensorEvent
typedef struct ASensorManager	ASensorManager
typedef struct ASensorEventQueue	ASensorEventQueue
typedef struct ASensor	ASensor
typedef ASensor const *	ASensorRef
typedef ASensorRef const *	ASensorList

Enumerations
enum	{   ASENSOR_TYPE_ACCELEROMETER = 1, ASENSOR_TYPE_MAGNETIC_FIELD = 2, ASENSOR_TYPE_GYROSCOPE = 4, ASENSOR_TYPE_LIGHT = 5,   ASENSOR_TYPE_PROXIMITY = 8 }
enum	{   ASENSOR_STATUS_NO_CONTACT = -1, ASENSOR_STATUS_UNRELIABLE = 0, ASENSOR_STATUS_ACCURACY_LOW = 1, ASENSOR_STATUS_ACCURACY_MEDIUM = 2,   ASENSOR_STATUS_ACCURACY_HIGH = 3 }
enum	{ AREPORTING_MODE_CONTINUOUS = 0, AREPORTING_MODE_ON_CHANGE = 1, AREPORTING_MODE_ONE_SHOT = 2, AREPORTING_MODE_SPECIAL_TRIGGER = 3 }

Functions
ASensorManager *	ASensorManager_getInstance ()
int	ASensorManager_getSensorList (ASensorManager *manager, ASensorList *list)
ASensor const *	ASensorManager_getDefaultSensor (ASensorManager *manager, int type)
ASensor const *	ASensorManager_getDefaultSensorEx (ASensorManager *manager, int type, bool wakeUp)
ASensorEventQueue *	ASensorManager_createEventQueue (ASensorManager *manager, ALooper *looper, int ident, ALooper_callbackFunc callback, void *data)
int	ASensorManager_destroyEventQueue (ASensorManager *manager, ASensorEventQueue *queue)
int	ASensorEventQueue_enableSensor (ASensorEventQueue *queue, ASensor const *sensor)
int	ASensorEventQueue_disableSensor (ASensorEventQueue *queue, ASensor const *sensor)
int	ASensorEventQueue_setEventRate (ASensorEventQueue *queue, ASensor const *sensor, int32_t usec)
int	ASensorEventQueue_hasEvents (ASensorEventQueue *queue)
ssize_t	ASensorEventQueue_getEvents (ASensorEventQueue *queue, ASensorEvent *events, size_t count)
const char *	ASensor_getName (ASensor const *sensor)
const char *	ASensor_getVendor (ASensor const *sensor)
int	ASensor_getType (ASensor const *sensor)
float	ASensor_getResolution (ASensor const *sensor)
int	ASensor_getMinDelay (ASensor const *sensor)
int	ASensor_getFifoMaxEventCount (ASensor const *sensor)
int	ASensor_getFifoReservedEventCount (ASensor const *sensor)
const char *	ASensor_getStringType (ASensor const *sensor)
int	ASensor_getReportingMode (ASensor const *sensor)
bool	ASensor_isWakeUpSensor (ASensor const *sensor)

Detailed Description

Macro Definition Documentation

#define ASENSOR_MAGNETIC_FIELD_EARTH_MAX   (60.0f)

Maximum magnetic field on Earth's surface in uT

#define ASENSOR_MAGNETIC_FIELD_EARTH_MIN   (30.0f)

Minimum magnetic field on Earth's surface in uT

#define ASENSOR_STANDARD_GRAVITY   (9.80665f)

Earth's gravity in m/s^2

Typedef Documentation

typedef struct AHeartRateEvent AHeartRateEvent

typedef struct AMetaDataEvent AMetaDataEvent

typedef struct ASensor ASensor

ASensor is an opaque type that provides information about an hardware sensors.

A ASensor pointer can be obtained using ASensorManager_getDefaultSensor(), ASensorManager_getDefaultSensorEx() or from a ASensorList.

This file provides a set of functions to access properties of a ASensor:

• ASensor_getName()
• ASensor_getVendor()
• ASensor_getType()
• ASensor_getResolution()
• ASensor_getMinDelay()
• ASensor_getFifoMaxEventCount()
• ASensor_getFifoReservedEventCount()
• ASensor_getStringType()
• ASensor_getReportingMode()
• ASensor_isWakeUpSensor()

typedef struct ASensorEvent ASensorEvent

typedef struct ASensorEventQueue ASensorEventQueue

ASensorEventQueue is an opaque type that provides access to ASensorEvent from hardware sensors.

A new ASensorEventQueue can be obtained using ASensorManager_createEventQueue().

This file provides a set of functions to enable and disable sensors, check and get events, and set event rates on a ASensorEventQueue.

• ASensorEventQueue_enableSensor()
• ASensorEventQueue_disableSensor()
• ASensorEventQueue_hasEvents()
• ASensorEventQueue_getEvents()
• ASensorEventQueue_setEventRate()

typedef ASensorRef const* ASensorList

ASensorList is an array of reference to ASensor.

A ASensorList can be initialized using ASensorManager_getSensorList().

typedef struct ASensorManager ASensorManager

ASensorManager is an opaque type to manage sensors and events queues.

ASensorManager is a singleton that can be obtained using ASensorManager_getInstance().

This file provides a set of functions that uses ASensorManager to access and list hardware sensors, and create and destroy event queues:

• ASensorManager_getSensorList()
• ASensorManager_getDefaultSensor()
• ASensorManager_getDefaultSensorEx()
• ASensorManager_createEventQueue()
• ASensorManager_destroyEventQueue()

typedef ASensor const* ASensorRef

ASensorRef is a type for constant pointers to ASensor.

This is used to define entry in ASensorList arrays.

typedef struct ASensorVector ASensorVector

A sensor event.

typedef struct AUncalibratedEvent AUncalibratedEvent

Enumeration Type Documentation

anonymous enum

Structures and functions to receive and process sensor events in native code. Sensor types. (keep in sync with hardware/sensor.h)

Enumerator
ASENSOR_TYPE_ACCELEROMETER	ASENSOR_TYPE_ACCELEROMETER reporting-mode: continuous All values are in SI units (m/s^2) and measure the acceleration of the device minus the force of gravity.
ASENSOR_TYPE_MAGNETIC_FIELD	ASENSOR_TYPE_MAGNETIC_FIELD reporting-mode: continuous All values are in micro-Tesla (uT) and measure the geomagnetic field in the X, Y and Z axis.
ASENSOR_TYPE_GYROSCOPE	ASENSOR_TYPE_GYROSCOPE reporting-mode: continuous All values are in radians/second and measure the rate of rotation around the X, Y and Z axis.
ASENSOR_TYPE_LIGHT	ASENSOR_TYPE_LIGHT reporting-mode: on-change The light sensor value is returned in SI lux units.
ASENSOR_TYPE_PROXIMITY	ASENSOR_TYPE_PROXIMITY reporting-mode: on-change The proximity sensor which turns the screen off and back on during calls is the wake-up proximity sensor. Implement wake-up proximity sensor before implementing a non wake-up proximity sensor. For the wake-up proximity sensor set the flag SENSOR_FLAG_WAKE_UP. The value corresponds to the distance to the nearest object in centimeters.

anonymous enum

Sensor accuracy measure.

Enumerator
ASENSOR_STATUS_NO_CONTACT	no contact
ASENSOR_STATUS_UNRELIABLE	unreliable
ASENSOR_STATUS_ACCURACY_LOW	low accuracy
ASENSOR_STATUS_ACCURACY_MEDIUM	medium accuracy
ASENSOR_STATUS_ACCURACY_HIGH	high accuracy

anonymous enum

Sensor Reporting Modes.

Enumerator
AREPORTING_MODE_CONTINUOUS	continuous reporting
AREPORTING_MODE_ON_CHANGE	reporting on change
AREPORTING_MODE_ONE_SHOT	on shot reporting
AREPORTING_MODE_SPECIAL_TRIGGER	special trigger reporting

Function Documentation

int ASensor_getFifoMaxEventCount

(

ASensor const *

sensor

)

Returns the maximum size of batches for this sensor. Batches will often be smaller, as the hardware fifo might be used for other sensors.

int ASensor_getFifoReservedEventCount

(

ASensor const *

sensor

)

Returns the hardware batch fifo size reserved to this sensor.

int ASensor_getMinDelay

(

ASensor const *

sensor

)

Returns the minimum delay allowed between events in microseconds. A value of zero means that this sensor doesn't report events at a constant rate, but rather only when a new data is available.

const char* ASensor_getName

(

ASensor const *

sensor

)

Returns this sensor's name (non localized)

int ASensor_getReportingMode

(

ASensor const *

sensor

)

Returns the reporting mode for this sensor. One of AREPORTING_MODE_* constants.

float ASensor_getResolution

(

ASensor const *

sensor

)

Returns this sensors's resolution

const char* ASensor_getStringType

(

ASensor const *

sensor

)

Returns this sensor's string type.

int ASensor_getType

(

ASensor const *

sensor

)

Return this sensor's type

const char* ASensor_getVendor

(

ASensor const *

sensor

)

Returns this sensor's vendor's name (non localized)

bool ASensor_isWakeUpSensor

(

ASensor const *

sensor

)

Returns true if this is a wake up sensor, false otherwise.

int ASensorEventQueue_disableSensor	(	ASensorEventQueue *	queue,
		ASensor const *	sensor
	)

Disable the selected sensor. Returns a negative error code on failure.

int ASensorEventQueue_enableSensor	(	ASensorEventQueue *	queue,
		ASensor const *	sensor
	)

Enable the selected sensor. Returns a negative error code on failure.

ssize_t ASensorEventQueue_getEvents	(	ASensorEventQueue *	queue,
		ASensorEvent *	events,
		size_t	count
	)

Returns the next available events from the queue. Returns a negative value if no events are available or an error has occurred, otherwise the number of events returned.

Examples: ASensorEvent event; ssize_t numEvent = ASensorEventQueue_getEvents(queue, &event, 1);

ASensorEvent eventBuffer[8]; ssize_t numEvent = ASensorEventQueue_getEvents(queue, eventBuffer, 8);

int ASensorEventQueue_hasEvents

(

ASensorEventQueue *

queue

)

Returns true if there are one or more events available in the sensor queue. Returns 1 if the queue has events; 0 if it does not have events; and a negative value if there is an error.

int ASensorEventQueue_setEventRate	(	ASensorEventQueue *	queue,
		ASensor const *	sensor,
		int32_t	usec
	)

Sets the delivery rate of events in microseconds for the given sensor. Note that this is a hint only, generally event will arrive at a higher rate. It is an error to set a rate inferior to the value returned by ASensor_getMinDelay(). Returns a negative error code on failure.

ASensorEventQueue* ASensorManager_createEventQueue	(	ASensorManager *	manager,
		ALooper *	looper,
		int	ident,
		ALooper_callbackFunc	callback,
		void *	data
	)

Creates a new sensor event queue and associate it with a looper.

"ident" is a identifier for the events that will be returned when calling ALooper_pollOnce(). The identifier must be >= 0, or ALOOPER_POLL_CALLBACK if providing a non-NULL callback.

int ASensorManager_destroyEventQueue	(	ASensorManager *	manager,
		ASensorEventQueue *	queue
	)

Destroys the event queue and free all resources associated to it.

ASensor const* ASensorManager_getDefaultSensor	(	ASensorManager *	manager,
		int	type
	)

Returns the default sensor for the given type, or NULL if no sensor of that type exists.

ASensor const* ASensorManager_getDefaultSensorEx	(	ASensorManager *	manager,
		int	type,
		bool	wakeUp
	)

Returns the default sensor with the given type and wakeUp properties or NULL if no sensor of this type and wakeUp properties exists.

ASensorManager* ASensorManager_getInstance

(

)

Get a reference to the sensor manager. ASensorManager is a singleton.

Example:

ASensorManager* sensorManager = ASensorManager_getInstance();

int ASensorManager_getSensorList	(	ASensorManager *	manager,
		ASensorList *	list
	)

Returns the list of available sensors.