GATT - Generic Attribute Profile Interface

Overview

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Files
file	att_errors.h
file	gatt_types.h
file	gatt_interface.h

Data Structures
struct	attPrepareWriteRequestParams_t
struct	gattAttribute_t
struct	gattCharacteristic_t
struct	gattService_t
struct	gattDbCharPresFormat_t
struct	gattHandleRange_t

Enumerations
enum	attErrorCode_t {   gAttErrCodeNoError_c, gAttErrCodeInvalidHandle_c, gAttErrCodeReadNotPermitted_c, gAttErrCodeWriteNotPermitted_c,   gAttErrCodeInvalidPdu_c, gAttErrCodeInsufficientAuthentication_c, gAttErrCodeRequestNotSupported_c, gAttErrCodeInvalidOffset_c,   gAttErrCodeInsufficientAuthorization_c, gAttErrCodePrepareQueueFull_c, gAttErrCodeAttributeNotFound_c, gAttErrCodeAttributeNotLong_c,   gAttErrCodeInsufficientEncryptionKeySize_c, gAttErrCodeInvalidAttributeValueLength_c, gAttErrCodeUnlikelyError_c, gAttErrCodeInsufficientEncryption_c,   gAttErrCodeUnsupportedGroupType_c, gAttErrCodeInsufficientResources_c }
enum	gattCccdFlags_t { gCccdEmpty_c, gCccdNotification_c, gCccdIndication_c }

Functions
bleResult_t	Gatt_Init (void)
bleResult_t	Gatt_GetMtu (deviceId_t deviceId, uint16_t *pOutMtu)

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Data Structure Documentation

attPrepareWriteRequestParams_t

struct attPrepareWriteRequestParams_t

Prepare Write Request Parameters Structure used by external reference.

Data Fields
uint16_t	attributeHandle
uint16_t	valueOffset
uint8_t	attributeValue[gAttMaxMtu_c - 5]
uint16_t	attributeLength

gattAttribute_t

struct gattAttribute_t

GATT Attribute structure definition.

Data Fields
uint16_t	handle	Attribute handle.
bleUuidType_t	uuidType	Type of the UUID.
bleUuid_t	uuid	The attribute's UUID.
uint16_t	valueLength	Length of the attribute value array.
uint16_t	maxValueLength	Maximum length of the attribute value array; if this is set to 0, then the attribute's length is fixed and cannot be changed.
uint8_t *	paValue	Attribute value array.

gattCharacteristic_t

struct gattCharacteristic_t

GATT Characteristic structure definition.

Data Fields
gattCharacteristicPropertiesBitFields_t	properties	Characteristic Properties as defined by GATT.
gattAttribute_t	value	Characteristic Value attribute.
uint8_t	cNumDescriptors	Size of the Characteristic Descriptors array.
gattAttribute_t *	aDescriptors	Characteristic Descriptors array.

gattService_t

struct gattService_t

GATT Service structure definition.

Data Fields
uint16_t	startHandle	The handle of the Service Declaration attribute.
uint16_t	endHandle	The last handle belonging to this Service (followed by another Service declaration of the end of the database).
bleUuidType_t	uuidType	Service UUID type.
bleUuid_t	uuid	Service UUID.
uint8_t	cNumCharacteristics	Size of the Characteristic array.
gattCharacteristic_t *	aCharacteristics	Characteristic array.
uint8_t	cNumIncludedServices	Size of the Included Services array.
struct gattService_tag *	aIncludedServices	Included Services array.

gattDbCharPresFormat_t

struct gattDbCharPresFormat_t

Characteristic Presentation Format Descriptor structure.

Data Fields
uint8_t	format
int8_t	exponent
uint16_t	unitUuid16
uint8_t	ns
uint16_t	description

gattHandleRange_t

struct gattHandleRange_t

GATT Handle Range structure definition.

Data Fields
uint16_t	startHandle	Start Handle.
uint16_t	endHandle	End Handle - shall be greater than or equal to Start Handle.

Enumeration Type Documentation

attErrorCode_t

enum attErrorCode_t

ATT error codes.

gattCccdFlags_t

enum gattCccdFlags_t

Flags for the value of the Client Characteristic Configuration Descriptor.

Enumerator
gCccdEmpty_c	Nothing is enabled.
gCccdNotification_c	Enables notifications.
gCccdIndication_c	Enabled indications.

Function Documentation

Gatt_Init()

bleResult_t Gatt_Init

(

void

)

---

Initializes the GATT module.

Remarks

If the GAP module is present, this function is called internally by Ble_HostInitialize(). Otherwise, the application must call this function once at device start-up.

This function executes synchronously.

Gatt_GetMtu()

bleResult_t Gatt_GetMtu	(	deviceId_t	deviceId,
		uint16_t *	pOutMtu
	)

---

Retrieves the MTU used with a given connected device.

Parameters

[in]	deviceId	The device ID of the connected peer.
[out]	pOutMtu	Pointer to integer to be written.

Returns

gBleSuccess_c or error.

Remarks

This function executes synchronously.