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HAL Class Reference

class HAL : public HALData

A set of static functions to get and set hardware attributes.

Inherits from

HAL
- HALData

Nested Classes and Structures

HAL::SEntry

Public Member Functions
IMPORT_C TInt	Get(TAttribute, TInt &)
IMPORT_C TInt	Get(TInt, TAttribute, TInt &)
IMPORT_C TInt	GetAll(TInt &, SEntry *&)
IMPORT_C TInt	Set(TAttribute, TInt)
IMPORT_C TInt	Set(TInt, TAttribute, TInt)

Public Member Enumerations
enum	TEntryProperty { EEntryValid = 0x1, EEntryDynamic = 0x2 }

Inherited Enumerations
	HALData:TAttribute
	HALData:TAttributeProperty
	HALData:TCPU
	HALData:TCPUABI
	HALData:TDeviceFamily
	HALData:TDigitiserOrientation
	HALData:TMachineUid
	HALData:TManufacturer
	HALData:TMouseState
	HALData:TPowerBackupStatus
	HALData:TPowerBatteryStatus
	HALData:TSystemStartupReason

Inherited Attributes
	HALData::EKeyboard_Full
	HALData::EKeyboard_Keypad

Member Functions Documentation

Get(TAttribute, TInt &)

IMPORT_C TInt	Get	(	TAttribute	aAttribute,
			TInt &	aValue
		)	[static]

Gets the value of the specified HAL attribute.

HALData::TAttribute HALData::TAttributeProperty

Parameters

TAttribute aAttribute	The HAL attribute.
TInt & aValue	On successful return, contains the attribute value. Some attributes may accept aValue as an input as well, to select one of several alternate values. See the documentation for the individual HAL attributes for details of this.

Get(TInt, TAttribute, TInt &)

IMPORT_C TInt	Get	(	TInt	aDeviceNumber,
			TAttribute	aAttribute,
			TInt &	aValue
		)	[static]

Gets the value of the specified HAL attribute.

HALData::TAttribute HALData::TAttributeProperty

Parameters

TInt aDeviceNumber	The device number. (eg: screen number)
TAttribute aAttribute	The HAL attribute.
TInt & aValue	On successful return, contains the attribute value. Some attributes may accept aValue as an input as well, to select one of several alternate values. See the documentation for the individual HAL attributes for details of this.

GetAll(TInt &, SEntry *&)

IMPORT_C TInt	GetAll	(	TInt &	aNumEntries,
			SEntry *&	aData
		)	[static]

Gets all HAL attributes, and their properties.

For attributes that are not meaningful on this device (ie. those which have not been defined in the config.hcf file), the attribute value and its associated property value are set to zero in the returned array.

Attributes for which multiple values can be retrieved ie. EDisplayIsPalettized, EDisplayBitsPerPixel, EDisplayOffsetToFirstPixel, EDisplayOffsetBetweenLines, and EDisplayPaletteEntry will also be zero in the returned array.

Attributes that allocate resources and open handles are also not returned by this API. Their value and property values will be set to zero in the returned array. Use HAL::Get() for these attributes.

Parameters

TInt & aNumEntries	On successful return, contains the total number of HAL attributes. If the function returns KErrNoMemory, this value is set to zero.
SEntry *& aData	On successful return, contains a pointer to an array of SEntry objects, each of which contains an attribute value and its property value. Note that the property value is defined by the HAL::TEntry synonym. If the function returns KErrNoMemory, this pointer is set to NULL.

Set(TAttribute, TInt)

IMPORT_C TInt	Set	(	TAttribute	aAttribute,
			TInt	aValue
		)	[static]

Sets the specified HAL attribute.

HALData::TAttribute HALData::TAttributeProperty

capability: WriteDeviceData or other capability specified for individual attributes in TAttribute

Parameters

TAttribute aAttribute	The HAL attribute.
TInt aValue	The attribute value.

Set(TInt, TAttribute, TInt)

IMPORT_C TInt	Set	(	TInt	aDeviceNumber,
			TAttribute	aAttribute,
			TInt	aValue
		)	[static]

Sets the specified HAL attribute.

HALData::TAttribute HALData::TAttributeProperty

capability: WriteDeviceData or other capability specified for individual attributes in TAttribute

Parameters

TInt aDeviceNumber	The device number. (eg: screen number)
TAttribute aAttribute	The HAL attribute.
TInt aValue	The attribute value.

Member Enumerations Documentation

Enum TEntryProperty

Synonyms for the attribute properties HALData::TAttributeProperty, and used in SEntry.

Enumerators

EEntryValid = 0x1	When set, means that an attribute is meaningful on this device.
EEntryDynamic = 0x2	When set, means that an attribute is modifiable.