This module describes functions and data structures used to implement an ATT client (central). More...

Modules
	Configuration
	This module describes parameters used to configure ATT client layer.

Data Structures
struct	bt_att_find_info_response_t
	Structure to store response to a "find info" request. More...

struct	bt_att_find_by_type_value_response_t
	Structure to store response to a "find by type value" request. More...

struct	bt_att_read_by_type_response_t
	Structure to store response to a "read by type" request. More...

struct	bt_att_read_by_group_type_response_t
	Structure to store response to a "read by group type" request. More...

struct	bt_att_client_evt_mtu_response_t
	Parameter to ATT_CLIENT_EVT_EXCHANGE_MTU_RESPONSE event. More...

struct	bt_att_client_evt_info_response_t
	Parameter to ATT_CLIENT_EVT_FIND_INFO_RESPONSE event. More...

struct	bt_att_client_evt_find_by_type_value_response_t
	Parameter to ATT_CLIENT_EVT_FIND_BY_TYPE_VALUE_RESPONSE event. More...

struct	bt_att_client_evt_read_by_type_response_t
	Parameter to ATT_CLIENT_EVT_READ_BY_TYPE_RESPONSE event. More...

struct	bt_att_client_evt_read_response_t
	Parameter to ATT_CLIENT_EVT_READ_RESPONSE event. More...

struct	bt_att_client_evt_read_blob_response_t
	Parameter to ATT_CLIENT_EVT_READ_BLOB_RESPONSE event. More...

struct	bt_att_client_evt_read_multiple_response_t
	Parameter to ATT_CLIENT_EVT_READ_MULTIPLE_RESPONSE event. More...

struct	bt_att_client_evt_read_by_group_type_response_t
	Parameter to ATT_CLIENT_EVT_READ_BY_GROUP_TYPE_RESPONSE event. More...

struct	bt_att_client_evt_write_response_t
	Parameter to ATT_CLIENT_EVT_WRITE_RESPONSE event. More...

struct	bt_att_client_evt_prepare_write_response_t
	Parameter to ATT_CLIENT_EVT_PREPARE_WRITE_RESPONSE event. More...

struct	bt_att_client_evt_execute_write_response_t
	Parameter to ATT_CLIENT_EVT_EXECUTE_WRITE_RESPONSE event. More...

struct	bt_att_client_evt_value_notification_t
	Parameter to ATT_CLIENT_EVT_VALUE_NOTIFICATION event. More...

struct	bt_att_client_evt_value_indication_t
	Parameter to ATT_CLIENT_EVT_VALUE_INDICATION event. More...

struct	bt_att_client_evt_conn_param_update_t
	Parameter to ATT_CLIENT_EVT_CONN_PARAM_UPDATE_REQUEST event. More...

struct	bt_att_client_evt_conn_param_update_completed_t
	Parameter to ATT_CLIENT_EVT_CONN_PARAM_UPDATE_COMPLETED event. More...

struct	bt_att_client_evt_write_cmd_sent_t
	Parameter to ATT_CLIENT_EVT_WRITE_COMMAND_SENT event. More...

struct	bt_att_client_evt_signed_write_cmd_sent_t
	Parameter to ATT_CLIENT_EVT_SIGNED_WRITE_COMMAND_SENT event. More...

union	bt_att_client_evt_t
	Parameter to ATT client application callback. More...

Functions
bt_bool	bt_att_client_init (void)
	Initialize the ATT client. More...

bt_att_client_mgr_t *	bt_att_get_client_mgr (void)
	Return a pointer to an instance of the ATT client manager. More...

bt_att_client_session_t *	bt_att_client_allocate_session (bt_att_client_session_callback_fp callback, void *callback_param)
	Allocate ATT client session. More...

void	bt_att_client_free_session (bt_att_client_session_t *session)
	Destroy ATT client session. More...

bt_bool	bt_att_client_connect (bt_att_client_session_t session, bt_bdaddr_t addr)
	Connect to a remote device (peripheral). More...

bt_bool	bt_att_client_disconnect (bt_att_client_session_t *session)
	Disconnect from a remote device. More...

bt_bool	bt_att_client_exchange_mtu (bt_att_client_session_t *session, bt_uint mtu)
	Exchange MTU. More...

bt_bool	bt_att_client_find_info (bt_att_client_session_t session, bt_uint start_handle, bt_uint end_handle, bt_att_find_info_response_t result, bt_uint max_results)
	Find Information. More...

bt_bool	bt_att_client_find_by_type_value (bt_att_client_session_t session, bt_uint start_handle, bt_uint end_handle, bt_uint type, const bt_byte value, bt_uint len, bt_att_find_by_type_value_response_t *result, bt_uint max_results)
	Find By Type Value. More...

bt_bool	bt_att_client_read_by_type (bt_att_client_session_t session, bt_uint start_handle, bt_uint end_handle, bt_uint type, bt_att_read_by_type_response_t result, bt_uint max_results)
	Read By Type (16-bit). More...

bt_bool	bt_att_client_read_by_type_80 (bt_att_client_session_t session, bt_uint start_handle, bt_uint end_handle, bt_uuid_t type, bt_att_read_by_type_response_t *result, bt_uint max_results)
	Read By Type (128-bit). More...

bt_bool	bt_att_client_read (bt_att_client_session_t *session, bt_uint handle)
	Read Attribute value. More...

bt_bool	bt_att_client_read_blob (bt_att_client_session_t *session, bt_uint handle, bt_uint offset)
	Read Blob. More...

bt_bool	bt_att_client_read_multiple (bt_att_client_session_t session, const bt_uint handles, bt_uint count)
	Read Multiple. More...

bt_bool	bt_att_client_read_by_group_type (bt_att_client_session_t session, bt_uint start_handle, bt_uint end_handle, bt_uint group_type, bt_att_read_by_group_type_response_t result, bt_uint max_results)
	Read By Group Type (16-bit). More...

bt_bool	bt_att_client_read_by_group_type_80 (bt_att_client_session_t session, bt_uint start_handle, bt_uint end_handle, bt_uuid_t group_type, bt_att_read_by_group_type_response_t *result, bt_uint max_results)
	Read By Group Type (128-bit). More...

bt_bool	bt_att_client_write (bt_att_client_session_t session, bt_uint handle, const bt_byte value, bt_uint len)
	Write Attribute Value. More...

bt_bool	bt_att_client_write_cmd (bt_att_client_session_t session, bt_uint handle, const bt_byte value, bt_uint len)
	Write Command. More...

bt_bool	bt_att_client_signed_write (bt_att_client_session_t session, bt_uint handle, const bt_byte value, bt_uint len, const bt_byte *signature)
	Signed Write Command. More...

bt_bool	bt_att_client_prepare_write (bt_att_client_session_t session, bt_uint handle, bt_uint value_offset, const bt_byte value, bt_uint len)
	Prepare Write. More...

bt_bool	bt_att_client_execute_write (bt_att_client_session_t *session, bt_byte flags)
	Execute Write. More...

bt_bool	bt_att_client_accept_conn_param_update (bt_att_client_session_t *session, bt_uint min_interval, bt_uint max_interval, bt_uint slave_latency, bt_uint supervision_timeout, bt_uint min_ce_length, bt_uint max_ce_length)
	Accept connection parameters update. More...

void	bt_att_client_reject_conn_param_update (bt_att_client_session_t *session)
	Reject connection parameters update. More...

bt_bdaddr_t *	bt_att_client_get_remote_address (const bt_att_client_session_t *session)
	Get the address of the remote device this device is connected to. More...

Events
#define	ATT_CLIENT_SESSION_EVT_SESSION_CONNECTED 1
	This event is generated when client connected to the server.

#define	ATT_CLIENT_SESSION_EVT_SESSION_DISCONNECTED 2
	This event is generated when client disconnected from the server.

#define	ATT_CLIENT_SESSION_EVT_CONNECTION_FAILED 3
	This event is generated when client failed to connect to the server.

#define	ATT_CLIENT_SESSION_EVT_TRAN_TIMEOUT 7
	This event is generated if operation (find, read, write) timed out.

#define	ATT_CLIENT_EVT_EXCHANGE_MTU_RESPONSE 10
	This event is generated when client received a response (either positive or negative) to a "exchange MTU" request.

#define	ATT_CLIENT_EVT_FIND_INFO_RESPONSE 11
	This event is generated when client received a response (either positive or negative) to a "find info" request.

#define	ATT_CLIENT_EVT_FIND_BY_TYPE_VALUE_RESPONSE 12
	This event is generated when client received a response (either positive or negative) to a "find by type value" request.

#define	ATT_CLIENT_EVT_READ_BY_TYPE_RESPONSE 13
	This event is generated when client received a response (either positive or negative) to a "read by type" request.

#define	ATT_CLIENT_EVT_READ_RESPONSE 14
	This event is generated when client received a response (either positive or negative) to a "read" request.

#define	ATT_CLIENT_EVT_READ_BLOB_RESPONSE 15
	This event is generated when client received a response (either positive or negative) to a "read blob" request.

#define	ATT_CLIENT_EVT_READ_MULTIPLE_RESPONSE 16
	This event is generated when client received a response (either positive or negative) to a "read multiple" request.

#define	ATT_CLIENT_EVT_READ_BY_GROUP_TYPE_RESPONSE 17
	This event is generated when client received a response (either positive or negative) to a "read by group type" request.

#define	ATT_CLIENT_EVT_WRITE_RESPONSE 18
	This event is generated when client received a response (either positive or negative) to a "write" request.

#define	ATT_CLIENT_EVT_PREPARE_WRITE_RESPONSE 19
	This event is generated when client received a response (either positive or negative) to a "preapare write" request.

#define	ATT_CLIENT_EVT_EXECUTE_WRITE_RESPONSE 20
	This event is generated when client received a response (either positive or negative) to a "execute write" request.

#define	ATT_CLIENT_EVT_VALUE_NOTIFICATION 21
	This event is generated when client received attribute value notification.

#define	ATT_CLIENT_EVT_VALUE_INDICATION 22
	This event is generated when client received attribute value indication.

#define	ATT_CLIENT_EVT_WRITE_COMMAND_SENT 23
	This event is generated when a write command has been sent.

#define	ATT_CLIENT_EVT_SIGNED_WRITE_COMMAND_SENT 24
	This event is generated when a signed write command has been sent.

#define	ATT_CLIENT_EVT_CONN_PARAM_UPDATE_REQUEST 50
	This event is generated when client received a "connection parameter update" request.

#define	ATT_CLIENT_EVT_CONN_PARAM_UPDATE_COMPLETED 51
	This event is generated after the new connection parameters have been sent.

Detailed Description

This module describes functions and data structures used to implement an ATT client (central).

Function Documentation

bt_bool bt_att_client_accept_conn_param_update	(	bt_att_client_session_t *	session,
		bt_uint	min_interval,
		bt_uint	max_interval,
		bt_uint	slave_latency,
		bt_uint	supervision_timeout,
		bt_uint	min_ce_length,
		bt_uint	max_ce_length
	)

Accept connection parameters update.

When a server sends "connection parameters update" request a ATT_CLIENT_EVT_CONN_PARAM_UPDATE_REQUEST event is generated. Client has to either accept the request or deny it. bt_att_client_accept_conn_param_update is used to accept the request.

Parameters

session	ATT session.
min_interval	Minimum connection interval expressed in 1.25ms units.
max_interval	Maximum connection interval expressed in 1.25ms units.
slave_latency	Slave latency expressed as number of connection events.
supervision_timeout	Link supervision timeout expressed in 10ms units.
min_ce_length	Information parameter about the minimum length of connection needed for this LE connection expressed in 0.625ms units.
max_ce_length	Information parameter about the maximum length of connection needed for this LE connection expressed in 0.625ms units.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_att_client_session_t* bt_att_client_allocate_session	(	bt_att_client_session_callback_fp	callback,
		void *	callback_param
	)

Allocate ATT client session.

This function allocates a new ATT client session.

Parameters

callback	The callback function that will be called when the ATT client generates an event.
callback_param	A pointer to arbitrary data to be passed to the `callback` callback.

Returns

A pointer to the new ATT client session structure if the function succeeds.
NULL otherwise.

bt_bool bt_att_client_connect	(	bt_att_client_session_t *	session,
		bt_bdaddr_t *	addr
	)

Connect to a remote device (peripheral).

This function establishes a connection to a remote device specified by the addr. If connection cannot be initiated for some reason, for example, there is not enough resources, it returns FALSE and no events are generated. Otherwise the result of an attempt to connect to the remote device is reported via the ATT client callback. The events generated will either be ATT_CLIENT_SESSION_EVT_SESSION_CONNECTED or ATT_CLIENT_SESSION_EVT_CONNECTION_FAILED.

Parameters

session	ATT session.
addr	The address of a remote device.

Returns

TRUE if connection establishment has been started.
FALSE otherwise.

bt_bool bt_att_client_disconnect ( bt_att_client_session_t * session )

Disconnect from a remote device.

This function closes a connection to a remote device. After the connection has been terminated the ATT client callback is called with ATT_CLIENT_SESSION_EVT_SESSION_CONNECTED event.

Parameters

session ATT session.

Returns

TRUE if disconnection has been started.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_exchange_mtu	(	bt_att_client_session_t *	session,
		bt_uint	mtu
	)

Exchange MTU.

This function informs the server about the client's MTU. In response to the "exchange MTU" request the server sends its MTU to the client.

Parameters

session	ATT session.
mtu	Client's MTU.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_execute_write	(	bt_att_client_session_t *	session,
		bt_byte	flags
	)

Execute Write.

This function sends a "execute write request to the client. ATT_CLIENT_EVT_EXECUTE_WRITE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
flags	This can be one of the following values: 0x00 - Cancel all prepared writes. 0x01 - Immediately write all pending prepared values.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_find_by_type_value	(	bt_att_client_session_t *	session,
		bt_uint	start_handle,
		bt_uint	end_handle,
		bt_uint	type,
		const bt_byte *	value,
		bt_uint	len,
		bt_att_find_by_type_value_response_t *	result,
		bt_uint	max_results
	)

Find By Type Value.

This function sends a "find by type value request to the client. ATT_CLIENT_EVT_FIND_BY_TYPE_VALUE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
start_handle	First requested handle number.
end_handle	Last requested handle number.
type	Attribute type.
value	Attribute value to find.
len	Length of the `value`.
result	Pointer to a buffer where response will be stored.
max_result	The maximum number of responses that `result` can store.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_find_info	(	bt_att_client_session_t *	session,
		bt_uint	start_handle,
		bt_uint	end_handle,
		bt_att_find_info_response_t *	result,
		bt_uint	max_results
	)

Find Information.

This function sends a "find information request to the client. ATT_CLIENT_EVT_FIND_INFO_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
start_handle	First requested handle number.
end_handle	Last requested handle number.
result	Pointer to a buffer where response will be stored.
max_result	The maximum number of responses that `result` can store.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

void bt_att_client_free_session ( bt_att_client_session_t * session )

Destroy ATT client session.

This function frees memory used by the session. The session has to exist and be in the "idle" state for this function to succeed. I.e. the session has to be disconnected before this function can be called.

Parameters

session ATT session.

Returns

TRUE if the function succeeds.
FALSE otherwise.

bt_bdaddr_t* bt_att_client_get_remote_address ( const bt_att_client_session_t * session )

Get the address of the remote device this device is connected to.

Parameters

session ATT client session.

Returns

A pointer to bt_bdaddr structure that contains the address of the remote device.

bt_bool bt_att_client_init ( void )

Initialize the ATT client.

This function initializes the ATT client of the stack. It must be called prior to any other ATT client function can be called.

bt_bool bt_att_client_prepare_write	(	bt_att_client_session_t *	session,
		bt_uint	handle,
		bt_uint	value_offset,
		const bt_byte *	value,
		bt_uint	len
	)

Prepare Write.

This function sends a "prepare write request to the client. ATT_CLIENT_EVT_PREPARE_WRITE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
handle	The handle of the attribute to be written.
value_offset	The offset of the first octet to be written.
value	The value to be written to the attribute.
len	The length of the `value`.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_read	(	bt_att_client_session_t *	session,
		bt_uint	handle
	)

Read Attribute value.

This function sends a "read request to the client. ATT_CLIENT_EVT_READ_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
handle	The handle of the attribute to be read.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_read_blob	(	bt_att_client_session_t *	session,
		bt_uint	handle,
		bt_uint	offset
	)

Read Blob.

This function sends a "read blob request to the client. ATT_CLIENT_EVT_READ_BLOB_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
handle	The handle of the attribute to be read.
offset	The offset of the first octet to be read.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_read_by_group_type	(	bt_att_client_session_t *	session,
		bt_uint	start_handle,
		bt_uint	end_handle,
		bt_uint	group_type,
		bt_att_read_by_group_type_response_t *	result,
		bt_uint	max_results
	)

Read By Group Type (16-bit).

This function sends a "read by group type request to the client. ATT_CLIENT_EVT_READ_BY_GROUP_TYPE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
start_handle	First requested handle number.
end_handle	Last requested handle number.
group_type	16-bit Attribute Group Type.
result	Pointer to a buffer where response will be stored.
max_result	The maximum number of responses that `result` can store.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_read_by_group_type_80	(	bt_att_client_session_t *	session,
		bt_uint	start_handle,
		bt_uint	end_handle,
		bt_uuid_t *	group_type,
		bt_att_read_by_group_type_response_t *	result,
		bt_uint	max_results
	)

Read By Group Type (128-bit).

This function sends a "read by group type request to the client. ATT_CLIENT_EVT_READ_BY_GROUP_TYPE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
start_handle	First requested handle number.
end_handle	Last requested handle number.
group_type	128-bit Attribute Group Type.
result	Pointer to a buffer where response will be stored.
max_result	The maximum number of responses that `result` can store.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_read_by_type	(	bt_att_client_session_t *	session,
		bt_uint	start_handle,
		bt_uint	end_handle,
		bt_uint	type,
		bt_att_read_by_type_response_t *	result,
		bt_uint	max_results
	)

Read By Type (16-bit).

This function sends a "read by type request to the client. ATT_CLIENT_EVT_READ_BY_TYPE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
start_handle	First requested handle number.
end_handle	Last requested handle number.
type	16-bit attribute type.
result	Pointer to a buffer where response will be stored.
max_result	The maximum number of responses that `result` can store.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_read_by_type_80	(	bt_att_client_session_t *	session,
		bt_uint	start_handle,
		bt_uint	end_handle,
		bt_uuid_t *	type,
		bt_att_read_by_type_response_t *	result,
		bt_uint	max_results
	)

Read By Type (128-bit).

This function sends a "read by type request to the client. ATT_CLIENT_EVT_READ_BY_TYPE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
start_handle	First requested handle number.
end_handle	Last requested handle number.
type	128-bit attribute type.
result	Pointer to a buffer where response will be stored.
max_result	The maximum number of responses that `result` can store.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_read_multiple	(	bt_att_client_session_t *	session,
		const bt_uint *	handles,
		bt_uint	count
	)

Read Multiple.

This function sends a "read blob request to the client. ATT_CLIENT_EVT_READ_MULTIPLE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
handles	The list of two or more handles.
count	The number of handles in `handles`.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

void bt_att_client_reject_conn_param_update ( bt_att_client_session_t * session )

Reject connection parameters update.

When a server sends "connection parameters update" request a ATT_CLIENT_EVT_CONN_PARAM_UPDATE_REQUEST event is generated. Client has to either accept the request or deny it. bt_att_client_reject_conn_param_update is used to deny the request.

Parameters

session ATT session.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_signed_write	(	bt_att_client_session_t *	session,
		bt_uint	handle,
		const bt_byte *	value,
		bt_uint	len,
		const bt_byte *	signature
	)

Signed Write Command.

This function sends a "signed write command request to the client. No event is generated.

Parameters

session	ATT session.
handle	The handle of the attribute to be written.
value	The value to be written to the attribute.
len	The length of the `value`.
signature	Authentication signature (12 bytes).

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_write	(	bt_att_client_session_t *	session,
		bt_uint	handle,
		const bt_byte *	value,
		bt_uint	len
	)

Write Attribute Value.

This function sends a "write request to the client. ATT_CLIENT_EVT_WRITE_RESPONSE event is generated when the response from the client has been received.

Parameters

session	ATT session.
handle	The handle of the attribute to be written.
value	The value to be written to the attribute.
len	The length of the `value`.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_bool bt_att_client_write_cmd	(	bt_att_client_session_t *	session,
		bt_uint	handle,
		const bt_byte *	value,
		bt_uint	len
	)

Write Command.

This function sends a "write command request to the client. No event is generated.

Parameters

session	ATT session.
handle	The handle of the attribute to be written.
value	The value to be written to the attribute.
len	The length of the `value`.

Returns

TRUE if a request has been sent.
FALSE otherwise. No events will be generated.

bt_att_client_mgr_t* bt_att_get_client_mgr ( void )

Return a pointer to an instance of the ATT client manager.

This function returns a pointer to an instance of the ATT client manager. There is only one instance of the manager allocated by the stack.

Returns

A pointer to the ATT client manager.

Modules

Data Structures

Functions

Events

Detailed Description

Function Documentation