pw::bluetooth::low_energy::Central2 Class Reference

Represents the LE central role. Used to scan and connect to peripherals. More...

#include <central2.h>

Inheritance diagram for pw::bluetooth::low_energy::Central2:

Classes
struct	ScanFilter
class	ScanHandle
	Represents an ongoing LE scan. More...
struct	ScanOptions
	Parameters used during a scan. More...
struct	ScanResult

Public Types
enum class	ScanType : uint8_t { kPassive , kActiveUsePublicAddress , kActiveUseRandomAddress , kActiveUseResolvablePrivateAddress }
enum class	ConnectError : uint8_t { kUnknownPeer , kInvalidOptions , kAlreadyExists , kCouldNotBeEstablished }
	Possible errors returned by Connect. More...
enum class	StartScanError : uint8_t { kScanInProgress , kInvalidParameters , kInternal }
using	ConnectResult = pw::expected< Connection2::Ptr, ConnectError >
	The result type returned by Connect().
using	ScanStartResult = pw::expected< ScanHandle::Ptr, StartScanError >
	The result type returned by Scan().

Public Member Functions
virtual async2::OnceReceiver< ConnectResult >	Connect (PeerId peer_id, Connection2::ConnectionOptions options)=0
virtual async2::OnceReceiver< ScanStartResult >	Scan (const ScanOptions &options)=0

Detailed Description

Represents the LE central role. Used to scan and connect to peripherals.

Member Enumeration Documentation

ConnectError

enum class pw::bluetooth::low_energy::Central2::ConnectError : uint8_t

strong

Possible errors returned by Connect.

Enumerator
kUnknownPeer	The peer ID is unknown.
kInvalidOptions	The ConnectionOptions were invalid.
kAlreadyExists	A connection to the peer already exists.
kCouldNotBeEstablished	The connection procedure failed at the link layer or timed out immediately after being established. A "could not be established" error was reported by the controller. This may be due to interference.

ScanType

enum class pw::bluetooth::low_energy::Central2::ScanType : uint8_t

strong

Enumerator
kActiveUsePublicAddress	Send scanning PDUs with the public address.
kActiveUseRandomAddress	Send scanning PDUs with the random address.
kActiveUseResolvablePrivateAddress	Send scanning PDUs with a generated Resolvable Private Address.

StartScanError

enum class pw::bluetooth::low_energy::Central2::StartScanError : uint8_t

strong

Enumerator
kScanInProgress	A scan is already in progress. Only 1 scan may be active at a time.
kInvalidParameters	Some of the scan options are invalid.
kInternal	An internal error occurred and a scan could not be started.

Member Function Documentation

Connect()

virtual async2::OnceReceiver< ConnectResult > pw::bluetooth::low_energy::Central2::Connect ( PeerId  peer_id, Connection2::ConnectionOptions  options  )

pure virtual

Connect to the peer with the given identifier.

The returned Connection2 represents the client's interest in the LE connection to the peer. Destroying all Connection2 instances for a peer will disconnect from the peer.

The Connection will be closed by the system if the connection to the peer is lost or an error occurs, as indicated by Connection.OnError.

Parameters

peer_id	Identifier of the peer to initiate a connection to.
options	Options used to configure the connection.

Returns

Returns a result when a connection is successfully established, or an error occurs.

Possible errors are documented in ConnectError.

Scan()

virtual async2::OnceReceiver< ScanStartResult > pw::bluetooth::low_energy::Central2::Scan ( const ScanOptions &  options )

pure virtual

Scans for nearby LE peripherals and broadcasters. The lifetime of the scan session is tied to the returned ScanHandle object in ScanStartResult. Once a scan is started, ScanHandle::PendResult can be called to get scan results. Only 1 scan may be active at a time.

Parameters

options

Options used to configure the scan session. These options are suggestions only, and the implementation may use different parameters to meet power or radio requirements.

Returns

Returns a ScanHandle object if the scan successfully starts, or a ScanError otherwise. ScanHandle::PendResult can be called to get ScanResults for LE peers that satisfy the filters indicated in options. The initial results may report recently discovered peers. Subsequent results will be reported only when peers have been scanned or updated since the last call.

Implemented in pw::bluetooth_sapphire::Central.

---

The documentation for this class was generated from the following file:

• pw_bluetooth/public/pw_bluetooth/low_energy/central2.h