SmartPhone Technologies LLC v. Amazon.Com, Inc., et al

Filing 1

COMPLAINT against Amazon Digital Services, Inc., Amazon.Com, Inc., ( Filing fee $ 350 receipt number 0540-3263866.), filed by SmartPhone Technologies LLC. (Attachments: # 1 Exhibit A - US 6,950,645 BI, # 2 Exhibit B - US 7,506,064 Bl, # 3 Exhibit C - US RE40,459 E, # 4 Exhibit D - US 6,956,562 BI, # 5 Exhibit E - US 6,466,236 BI, # 6 Civil Cover Sheet)(Ward, Thomas)

111111

1111111111111111111111111111111111111111111111111111111111111
US006950645Bl

(54)

United States Patent

(10)

Kammer et ai.

(12)

(45)

2004/0218556 A1 * 11/2004 Son et al. ................... 370/311
2005/0070340 A1 * 3/2005 Kim ........................... 455/574

POWER-CONSERVING INTUITIVE DEVICE
DISCOVERY TECHNIQUE IN A
BLUETOOTH ENVIRONMENT

(75)

Assignee: Palm Source, Inc., Sunnyvale, CA (US)

( *)

Notice:

(21)

Appl. No.: 09/675,047

(22)

Filed:

(51)
(52)

* cited by examiner

Inventors: David Kammer, Seattle, WA (US); E.
Michael Lunsford, San Carlos, CA
(US)

(73)

Patent No.:
US 6,950,645 BI
Date of Patent:
Sep.27,200S

Int. CI? ................................................. H04B 1/16
U.S. CI. .................. 455/343.1; 455/41.2; 455/574;
370/338
Field of Search .......................... 455/343.1-343.3,
455/41.2,41.3,574; 370/338,311

Primary Examiner-Lana Le
(74) Attorney, Agent, or Firm-Berry & Associates P.c.
ABSTRACT

(57)

(58)
(56)

A method and system for managing when a responder device
(a device having a transceiver for wireless communication)
is operating in a discoverable mode in a wireless network of
devices, such as a Bluetooth network. In the discoverable
mode, the responder device is set to scan for and respond to
general inquiry messages broadcast from another device
(e.g., an initiator device). When in the non-discoverable
mode, the responder device will not respond to and/or scan
for general inquiry messages broadcast from an initiator
device. The responder device automatically enters the discoverable mode when the responder device enters into its
awake mode. The responder device automatically enters the
non-discoverable mode when the device enters into its sleep
mode. Therefore, the responder device will be in discoverable mode for a reduced period of time, and as such will
respond to fewer general inquiry messages. Accordingly,
fewer messages will be exchanged between devices in the
wireless network, simplifying the device discovery process
for users and conserving the battery resources of the initiator
and responder devices.

Subject to any disclaimer, the term of this
patent is extended or adjusted under 35
U.S.c. 154(b) by 553 days.

Sep. 28, 2000

References Cited
U.S. PATENT DOCUMENTS

5,625,882
5,657,317
5,682,379
6,438,585
6,529,748
2004/0125776

A * 4/1997 Vook et al. .............. 455/343.4
A * 8/1997 Mahany et al. .......... 455/343.1
A * 10/1997 Mahany et al. .......... 455/343.1
B2 * 8/2002 Mousseau et al. ......... 455/41.2
B1 * 3/2003 Bruner .................... 455/343.2
A1 * 7/2004 Haugli et al. ............... 370/338

26 Claims, 8 Drawing Sheets

810
INQUIRY MESSAGE BROADCAST BY INITIATOR DEVICE

~

~

830

850

RESPONDER DEVICE IN
DISCOVERABLE MODE

RESPONDER DEVICE IN
NON-DISCOVERABLE MODE

840

!l§Q
RESPONDER DEVICE
DISREGARDS INQUIRY
MESSAGE

~
RESPONDER DEVICE
RESPONDS TO INQUIRY
MESSAGE

l!ZQ
RESPONDER DEVICE IN
CONNECTABLE MODE

~
!l§Q
RESPONDER DEVICE
RESPONDS TO PAGES
(NAME REQUESTS)

u.s.

Patent

Sep.27,200S

US 6,950,645 BI

Sheet 1 of 8

INQUIRIES
40f

40d
409

.... ~
~,

INQUIRY 40

"

40h

T

INQUIRY REPONSE ~

..
..

PAGE44a
20
INITIATOR
DEVICE

PAGE RESPONSE 46a

...

..

NAME REQUEST 48a

30
RESPONDING
DEVICE

NAME REQUEST RESPONSE 50a

~~

INQUIRY 40 ~ ~

INQUIRY 40
INQUIRY REPONSE 42b

INQUIRY REPONSE 42c

PAGE 44b

PAGE44c

PAGE RESPONSE 46b

PAGE RESPONSE 46c

NAME REQUEST 48b

NAME REQUEST 48c

NAME REQUEST RESPONSE 50b

NAME REQUEST RESPONSE 50c

"
32

22
(SECOND)
INITIATOR
DEVICE

(SECOND)
RESPONDING
DEVICE

Figure 1
(Prior Art)

~r

u.s.

Patent

Sep.27,200S

Sheet 2 of 8

Figure 2

US 6,950,645 BI

u.s.

Patent

Sep.27,200S

US 6,950,645 BI

Sheet 3 of 8

RADIO
SIGNAL

~
RFMODULE
~

ANTENNA 305

-

.....

..

LINK
CONTROLLER
~

....-

...

MICROCONTROLLER
a.3Q

....
-

.
..

INTERFACE

MQ

j!lo

BUS300~

"

BLUETOOTHENABLED DEVICE
~

Figure 3

u.s.

Patent

Sep.27,200S

US 6,950,645 BI

Sheet 4 of 8

ROM
NON·VOLATILE

450

RAM
VOLATILE

~

PROCESSOR

liQ

DATA
STORAGE
DEVICE

490

HOST INTERFACE
CIRCUITRY

420

1

DSP~

I

I

\

300

-------- -------------- ----------------- ------------------ -----------------------------------------------

DISPLAY
DEVICE

440

(PAD)
ALPHA·
NUMERIC
INPUT

ON·
SCREEN
CURSOR
CONTROL

460

480

TRANSCEIVER

3M

Figure 4

u.s.

Patent

Sep.27,200S

Sheet 5 of 8

US 6,950,645 BI

USER INTERFACE CIRCUIRTY MQ

COMM
INTERFACE

DISPLAY
INPUT

DISPLAY
OUTPUT

580

570

560

V

300

PROCESSOR

430

RAM VOLATILE

450

~

IR PROTOCOL
STACK

RF PROTOCOL
STACK

DATA STORAGE
DEVICE

520

~

ill

490

1+-528
420

522-.

IR CIRCUITRY

~

RF CIRCUITRY

530

524

IR INTERFACE
PORT

RF INTERFACE
PORT

ill

lli

TRANSCEIVER
~

Figure 5

u.s.

Patent

Sep.27,200S

Sheet 6 of 8

US 6,950,645 BI

OBJECT EXCHANGE
PROTOCOL
670

TELEPHONY CONTROL
PROTOCOL
640

RFCOMM
§.5.Q

SERVICE DISCOVERY
PROTOCOL
2.6Q

LOGICAL LINK CONTROL AND ADAPTATION PROTOCOL 630
LINK MANAGER PROTOCOL Q2Q

BASEBAND (LINK CONTROLLER) 320

Figure 6

u.s.

Patent

Sep.27,200S

INQUIRY 740

....

US 6,950,645 BI

Sheet 7 of 8

..
....

~

720
INITIATOR
DEVICE

INQUIRY RESPONSE 742
PAGE 744

730
RESPONDER
DEVICE
(DISCOVERABLE)

..
....

...
....
PAGE RESPONSE 746

Figure 7A

INQUIRY 740

..
.....

720
INITIATOR
DEVICE

PAGE 744

...
.....
PAGE RESPONSE 746

Figure 78

...
...

730
RESPONDER
DEVICE
(NONDISCOVERABLE)

u.s.

Patent

Sep.27,200S

US 6,950,645 BI

Sheet 8 of 8

810
INQUIRY MESSAGE BROADCAST BY INITIATOR DEVICE

~

~
830

850

RESPONDER DEVICE IN
DISCOVERABLE MODE

RESPONDER DEVICE IN
NON-DISCOVERABLE MODE

840

"

860

RESPONDER DEVICE
RESPONDS TO INQUIRY
MESSAGE

RESPONDER DEVICE
DISREGARDS INQUIRY
MESSAGE

"

...

-

870
RESPONDER DEVICE IN
CONNECTABLE MODE

"

880
RESPONDER DEVICE
RESPONDS TO PAGES
(NAME REQUESTS)

Figure 8

...
...

US 6,950,645 Bl
1
POWER-CONSERVING INTUITIVE DEVICE
DISCOVERY TECHNIQUE IN A
BLUETOOTH ENVIRONMENT

2

casts an inquiry 40, it typically remains in the inquiry state
for 10.24 seconds (this time is programmable, but the
Bluetooth specification recommends 10.24 seconds).
In order to receive and respond to inquiry 40, responder
TECHNI CAL FIELD
5 devices 30 and 32 must be "discoverable" (e.g., the devices
must be scanning for inquiry messages). According to the
The present invention relates to networks of devices that
Bluetooth specification referenced above, a discoverable
can be connected using wireless links, in particular devices
device enters into "inquiry scan" (scanning for inquiry
that use the Bluetooth technology. Specifically, the present
invention pertains to a method and system for managing the 10 messages) every 2.56 seconds and remains in inquiry scan
for 10.625 milliseconds.
Bluetooth device discovery process.
Responder devices 30 and 32 send inquiry responses 42a
BACKGROUND ART
and 42b, respectively, to initiator device 20 in response to
inquiry 40. Inquiry responses 42a and 42b provide the
Computer systems and other types of consumer electronic 15 Bluetooth device addresses (a numerical address or a device
devices are commonly linked to each other and to peripheral
access code) for responder devices 30 and 32, and optionally
devices using a myriad of different types of cables and
provide additional information such as the clock, class of
connectors. As these devices grow in number and variety,
device and page scan mode. Inquiry responses 42a and 42b
their cables and connectors can often become quite cumdo not provide a name (or user-friendly name) for responder
bersome to work with. Accordingly, efforts are underway to 20 devices 30 and 32. The user-friendly name can be up to 248
develop technologies allowing hardware connections to be
characters long and is not provided in order to reduce the
replaced with wireless ones.
length of the inquiry responses.
One such technology is the Bluetooth technology. BlueInitiator device 20 can therefore receive an inquiry
tooth is the code name for a technology specification for
response from multiple Bluetooth devices (e.g., responder
short-range radio links that will allow the many proprietary 25
devices 30 and 32), providing each devices' numerical
cables that connect devices to one another to be replaced
address at least. Generally, a user will not be able to identify
with short-range radio links.
one type of responder device over another based only on the
The Bluetooth technology is based on a high-perfordevice's numerical address. For example, there may be two
mance, yet low-cost, integrated radio transceiver. For
printers in proximity, and the user generally will not be able
instance, Bluetooth transceivers built into both a cellular 30
to tell which printer to connect with based on the numerical
telephone and a laptop computer system would replace the
address. However, "user-friendly names" can be used to
cables used today to connect a laptop to a cellular telephone.
identify each printer's location and features, allowing the
Printers, personal digital assistants (palmtop computer sysuser to make a selection of one over the other. Therefore,
tems, hand-held devices and the like), desktop computer
initiator device 20 needs to discover and display the usersystems, fax machines, keyboards, joysticks and virtually 35
friendly name for each of the devices that responded, so that
any other digital device can be part of a Bluetooth system.
the user can select the appropriate device with which to
Bluetooth radio technology can also provide a universal
connect.
bridge to existing data networks and a mechanism to form
To accomplish this, initiator device 20 must connect one
small private ad hoc groupings ("scatternets" or "piconets")
of connected devices away from fixed network infrastruc- 40 device at a time to each of the responder devices 30 and 32
in order to request a user-friendly name. Accordingly, initures.
tiator device 20 sends pages 44a and 44b to each device that
The Bluetooth technology allows Bluetooth devices to
responded to inquiry 40. In response to the pages 44a and
"discover" other Bluetooth devices that are within range and
44b, responder devices 30 and 32 send page responses 46a
then connect with those devices, either automatically or at a
45 and 46b, respectively. Page responses 46a and 46b provide
user's discretion. The Generic Access Profile (GAP) of the
the user-friendly name for responder devices 30 and 32,
Bluetooth specification (Section 6 of "Specification of the
respectively.
Bluetooth System, Core," version 1.0B, dated Dec. 1, 1999,
Next, initiator device 20 will send name requests 48a and
herein incorporated by reference as background) describes
48b to responder devices 30 and 32, respectively. In
the processes by which Bluetooth devices discover each
other. The device discovery process has two primary steps: 50 response to name request 48a, responder device 30 sends
name request response 50a to initiator device 20. Similarly,
an inquiry step (described in Sections 6.1 and 6.2 of the
in response to name request 48b, responder device 32 sends
Bluetooth specification), and a name discovery step (dename request response 50b to initiator device 20. Name
scribed in Section 6.3 of the Bluetooth specification). In the
request responses 50a and 50b provide the user-friendly
inquiry step, the Bluetooth devices make their presence
known to each other and exchange attributes (e.g., 55 names for responding devices 30 and 32, respectively. The
user-friendly names are displayed to the user, who can then
addresses) needed to further the connection process. In the
select one or more of the responder devices with which to
name discovery step, user-friendly names are exchanged to
connect.
help a user identify Bluetooth devices that are in the environment. The inquiry and discovery steps are described in
There are a number of disadvantages associated with the
further detail below.
60 Bluetooth device discovery process described above. One
Prior Art FIG. 1 is a data flow diagram 10 illustrating the
disadvantage is that, while in discoverable mode, responder
device discovery process used by one Bluetooth device
devices 30 and 32 are scanning for and receiving messages,
(initiator device 20) to discover another Bluetooth device
and thus are consuming power. In addition, when an inquiry
(e.g., responder device 30). First, initiator device 20 sends
40 is received, responder devices 30 and 32 will send an
(broadcasts) a general inquiry message (e.g., inquiry 40) 65 inquiry response (e.g., 42a and 42b, respectively) to initiator
device 20, consuming more power. Thus, even when
over the nominal range of a typical Bluetooth device (e.g.,
approximately 10 meters). When initiator device 20 broadresponder devices 30 and 32 are powered down (turned oft),

US 6,950,645 Bl

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4

they can still be scanning for, receiving and responding to
many Bluetooth devices are being designed and manufacinquiry messages, and as such will continue to consume
tured according to the Bluetooth specification. Consepower.
quently, a solution that relies on a significant deviation from
Power consumption is of particular concern to limited
the Bluetooth specification will create new problems, such
power devices (battery-powered devices) such as laptop 5 as incompatibility between newer Bluetooth devices and
legacy Bluetooth devices. An aim of the Bluetooth specificomputer systems, cell phones, personal digital assistants
cation is to provide a level of standardization across all
(PDAs), including palmtop computer systems, hand-held
devices, and the like. These devices are limited in size and
Bluetooth devices, and a substantial deviation from the
weight, and therefore they typically use smaller and lighter
specification would be contrary to that aim. Accordingly,
batteries of limited capacity. As described above, when 10 any solution to the prior art problems described above
PDAs and other such devices are turned off (powered down),
should be satisfactorily consistent with the Bluetooth specithey may remain discoverable in the Bluetooth environment.
fication, or it should be a solution that can be incorporated
Consequently, even when powered down, these devices will
into legacy Bluetooth devices.
scan for and receive general inquiry messages (e.g., inquiry
DISCLOSURE OF THE INVENTION
40), and will send responses (e.g., inquiry response 42a) to 15
such messages, and thus will continue to draw from their
Accordingly, a need exists for a system and/or method for
limited battery power. Thus, the Bluetooth device discovery
managing the Bluetooth device discovery process. A need
process can consume the limited power (battery) resources
also exists for a system and/or method that can satisfy the
that are typically available to PDAs and other such devices.
Accordingly, more frequent battery charges may be needed, 20 above need and that can reduce the burden on the limited
power resources available to many types of Bluetooth
inconveniencing the user.
devices. In particular, a need exists for a system and/or
This problem is exacerbated as Bluetooth devices grow in
method that can satisfy the above needs and that is consistent
number and popularity. With more Bluetooth devices in use,
with the Bluetooth specification, and that can be implea device (such as responder device 30) will receive inquiries
(e.g., 40c-40h) from each of the many possible initiator 25 mented in Bluetooth-enabled devices including legacy Bluetooth devices. What is also needed is a system and/or method
devices in broadcast range. Furthermore, each inquiry
that can satisfy the above needs and that is user-friendly. The
40c-40h engenders an inquiry response from responder
present invention provides these advantages and others not
device 30, accelerating the rate of power consumption.
specifically mentioned above but described in the sections to
Another disadvantage to the Bluetooth device discovery
process is that it can become unmanageably large, especially 30 follow.
The present invention pertains to method and system for
with the increasing number of Bluetooth devices. That is, as
managing when a responder device (a device having a
the number of Bluetooth devices grows, an increasing numtransceiver for wireless communication) is operating in a
ber of messages (inquiries and inquiry responses, and pages
discoverable mode in a wireless network of devices. In
and page responses) will be generated as each device undertakes the device discovery process. The probability that 35 accordance with the present embodiment of the present
invention, the responder device automatically enters the
these messages will collide with other will likely increase,
discoverable mode when the responder device enters into its
increasing the frequency at which messages have to be
awake mode. The responder device automatically enters a
retransmitted. Devices responding to one message will have
non-discoverable mode when the device enters into its
to ignore other messages, and the messages that are ignored
will have to be retransmitted. The increase in messages will 40 standby (or sleep) mode. In the discoverable mode, the
responder device is set to scan for and/or respond to wireless
further increase the burden on the limited power resources of
signals that are broadcast from another device (e.g., an
both initiator and responding Bluetooth devices.
initiator device). When in the non-discoverable mode, the
In addition, in the name discovery step of the device
responder device will not scan for and/or will not respond to
discovery process, each device provides its user-friendly
name for display to the user. As the number of Bluetooth 45 wireless signals broadcast from an initiator device. In a
preferred embodiment, the devices are Bluetooth-enabled
devices continues to grow, the length of the list of userdevices. In one Bluetooth embodiment, when in the nonfriendly names will grow as well, which can complicate the
discoverable (standby or sleep) mode, the responder device
user experience.
will not scan for and/or will not respond to general inquiry
Yet another problem with the Bluetooth device discovery
process is that an initiator device 20 can undertake the 50 messages broadcast by an initiator device.
In another Bluetooth embodiment, the responder device
process and connect with responder device 730 without the
will be in the connectable mode at all times (even when in
user's knowledge and permission. Thus, for example, inithe non-discoverable or standby mode). In the connectable
tiator device 20 can retrieve the user-friendly name and the
mode, the responder device will respond to wireless signals
address of responder device 30, even if the user has no desire
55 (such as pages or name requests) directed to the responder
to share this information with unknown devices.
device. Accordingly, embodiments of the present invention
One possible solution to the problems described above is
reduce the time that the responder device can be discovered
to allow the user to manage the device discovery process.
by unknown initiator devices, but still allow the responder
However, this solution is also problematic because it
device to make a connection with a known initiator device
requires the user to learn and understand the device discovery process defined by the Bluetooth specification. This may 60 (that is, an initiator device that has previously completed the
device discovery process with the responder device).
be beyond the capability of some users, while other users
Therefore, in accordance with the present invention, the
would instead prefer a user-friendly process that either fits
responder device automatically makes itself discoverable or
into a usage model that they already understand.
non-discoverable depending on whether the device is,
Thus, the Bluetooth device discovery process presents a
number of problems. Finding a solution to these problems is 65 respectively, awake (powered on) or asleep (powered off).
made more complex because the solution must be substanAccordingly, the device discovery process can be managed
tially compliant with the Bluetooth specification. That is,
in a way that is both user-friendly and intuitively understood

US 6,950,645 Bl
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by the user; that is, when the responder device is powered on
and equivalents, which may be included within the spirit and
by the user, it is made discoverable, and when the responder
scope of the invention as defined by the appended claims.
device is powered off, it is made non-discoverable. As a
Furthermore, in the following detailed description of the
result, the responder device will be in discoverable mode for
present invention, numerous specific details are set forth in
a reduced period of time, conserving power (battery) 5 order to provide a thorough understanding of the present
resources. In addition, the responder device will respond to
invention. However, it will be obvious to one of ordinary
fewer general inquiry messages, which will also reduce the
skill in the art that the present invention may be practiced
number of messages that are generated as a result of the
without these specific details. In other instances, well-known
inquiry responses (such as pages and page responses, and
methods, procedures, components, and circuits have not
name requests and responses to name requests). Conse- 10 been described in detail so as not to unnecessarily obscure
quently, devices in the wireless network will exchange fewer
aspects of the present invention.
messages, simplifying the device discovery process for users
Some portions of the detailed descriptions that follow are
as well as conserving the power (battery) resources of
presented in terms of procedures, logic blocks, processing,
initiator devices as well as responder devices. With devices
and other symbolic representations of operations on data bits
in the discoverable mode for reduced periods of time, the 15 within a computer memory. These descriptions and reprenumber of user-friendly names exchanged between devices
sentations are the means used by those skilled in the data
will decrease, simplifying the user experience.
processing arts to most effectively convey the substance of
These and other objects and advantages of the present
their work to others skilled in the art. A procedure, logic
invention will become obvious to those of ordinary skill in
block, process, etc., is here, and generally, conceived to be
the art after having read the following detailed description of 20 a self-consistent sequence of steps or instructions leading to
the preferred embodiments which are illustrated in the
a desired result. The steps are those requiring physical
various drawing figures.
manipulations of physical quantities. Usually, though not
necessarily, these quantities take the form of electrical or
BRIEF DESCRIPTION OF THE DRAWINGS
magnetic signals capable of being stored, transferred, com25 bined, compared, and otherwise manipulated in a computer
The accompanying drawings, which are incorporated in
system. It has proven convenient at times, principally for
and form a part of this specification, illustrate embodiments
reasons of common usage, to refer to these signals as bits,
of the invention and, together with the description, serve to
bytes, values, elements, symbols, characters, terms, numexplain the principles of the invention:
bers, or the like.
PRIOR ART FIG. 1 is a data flow diagram illustrating one 30
It should be borne in mind, however, that all of these and
embodiment of a prior art device discovery process.
similar terms are to be associated with the appropriate
FIG. 2 illustrates a network of devices coupled using
physical quantities and are merely convenient labels applied
wireless connections in accordance with one embodiment of
to these quantities. Unless specifically stated otherwise as
the present invention.
FIG. 3 is a block diagram showing one embodiment of a 35 apparent from the following discussions, it is appreciated
that throughout the present invention, discussions utilizing
Bluetooth wireless transceiver in accordance with the
terms such as "setting," "storing," "scanning," "receiving,"
present invention.
"sending," "disregarding," "entering," or the like, refer to
FIG. 4 is a block diagram of an exemplary portable
the action and processes (e.g., process 800 of FIG. 8) of a
computer system coupled to the Bluetooth wireless transceiver of FIG. 3 in accordance with one embodiment of the 40 computer system or similar intelligent electronic computing
device, that manipulates and transforms data represented as
present invention.
physical ( electronic) quantities within the computer sysFIG. 5 is a block diagram showing features of the portable
tem's registers and memories into other data similarly
computer system of FIG. 4 in accordance with one embodirepresented as physical quantities within the computer sysment of the present invention.
45 tem memories or registers or other such information storage,
FIG. 6 is a block diagram illustrating a protocol stack used
transmission or display devices.
by a Bluetooth-enabled device in accordance with one
The present invention is discussed primarily in a context
embodiment of the present invention.
in which devices and systems are coupled using wireless
FIG. 7A is a data flow diagram illustrating a device
links, and specifically with regard to devices and systems
discovery process for a discoverable device in accordance
50 compliant with the Bluetooth technology. Bluetooth is the
with one embodiment of the present invention.
code name for a technology specification for small form
FIG. 7B is a data flow diagram illustrating a device
factor, low-cost, short-range radio links between personal
discovery process for a non-discoverable device in accorcomputers (PCs), personal digital assistants (PDAs), mobile
dance with one embodiment of the present invention.
phones and other devices. The Bluetooth technology allows
FIG. 8 is a flowchart of the steps for managing a device
discovery process in accordance with one embodiment of 55 cables that connect devices to one another to be replaced
with short-range radio links. However, it is appreciated that
the present invention.
the present invention may be utilized with devices and
systems coupled using technologies and/or protocols differBEST MODE FOR CARRYING OUT THE
ent from Bluetooth, including but not limited to infrared
INVENTION
60 communications links as defined by the Infrared Data Association (IrDA).
Reference will now be made in detail to the preferred
In the parlance of Bluetooth, a collection of devices
embodiments of the invention, examples of which are illusconnected in a Bluetooth system is referred to as a "piconet"
trated in the accompanying drawings. While the invention
or a "subnet." A piconet starts with two connected devices,
will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to 65 such as a computer system and a cellular phone, and may
limit the invention to these embodiments. On the contrary,
grow to eight connected devices. All Bluetooth devices are
the invention is intended to cover alternatives, modifications
peer units; however, when establishing a piconet, one unit

US 6,950,645 Bl
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8

will act as a master and the other(s) as slave(s) for the
page scan, inquiry, inquiry scan, master response, slave
duration of the piconet connection.
response, and inquiry response. The substates are interim
A Bluetooth system supports both point-to-point and
states that are used to add new slaves to a piconet (FIG. 2).
point-to-multi-point connections. Several piconets can be
Continuing with reference to FIG. 3, in one embodiment,
established and linked together in a "scatternet," where each 5 microcontroller 330 is an application specific integrated
circuit (ASIC). In the Bluetooth embodiment, microcontrolpiconet is identified by a different frequency hopping
sequence. All devices participating on the same piconet are
ler 330 is a separate central processing unit (CPU) core for
synchronized to their respective hopping sequence.
managing transceiver 308 and for handling some inquiries
FIG. 2 illustrates the topology of a network 200 of devices
and requests without having to involve the host device. In
coupled using wireless connections in accordance with one 10 the Bluetooth embodiment, microcontroller 330 runs software that discovers and communicates with other Bluetooth
embodiment of the present invention. Devices 210, 220, 230
and 240 are coupled in piconet 201 using wireless connecdevices via the Link Manager Protocol (LMP). The LMP
tions 280a-c. Similarly, devices 250, 260 and 270 are
provides a number of services including sending and receivcoupled in piconet 202 using wireless connections 280e-f.
ing of data, inquiring of and reporting a name or device
Piconet 201 and piconet 202 are coupled using wireless 15 identifier, making and responding to link address inquiries,
connection setup, authentication, and link mode negotiation
connection 280d. Devices 210-270 can be printers, personal
and setup. The LMP also can be used to place transceiver
digital assistants (PDAs), desktop computer systems, laptop
308 in "sniff" mode, "hold" mode, "park" mode or
computer systems, cell phones, fax machines, keyboards,
"standby" mode. Refer also to FIG. 6, below.
joysticks and virtually any other device. In the present
embodiment, devices 210-270 are Bluetooth devices; that is, 20
The hold mode is a power saving mode that can be used
for connected units if no data need to be transmitted. The
they are equipped with a Bluetooth radio transceiver, or they
are adapted to communicate with Bluetooth devices ("Bluesniff and park modes are also low power modes. In the sniff
tooth-enabled"). The Bluetooth radio transceiver may be
mode, a device listens to the piconet at a reduced rate
integrated into a device, or it may be coupled to a device.
(relative to the regular rate), thus reducing its duty cycle.
FIG. 3 is a block diagram of one embodiment of a 25 The sniff interval is programmable and depends on the
transceiver 308 in accordance with the present invention. In
application. In the park mode, a device is still synchronized
a preferred embodiment (the "Bluetooth embodiment"),
to the piconet but does not participate in the traffic.
transceiver 308 is a Bluetooth device comprising a digital
In the present embodiment, before any connections
component (e.g., a Bluetooth controller) and an analog
between Bluetooth devices are created, all devices are in
30 standby mode; that is, the standby mode is the default mode
component (e.g., a Bluetooth radio).
In the present embodiment, transceiver 308 comprises an
of a Bluetooth device. The standby mode is a low power
mode in which an unconnected unit "listens" for messages
antenna 305 for receiving or transmitting radio signals, a
at a regular rate (generally, every 2.56 seconds according to
radio frequency (RF) module 310, a link controller 320, a
the Bluetooth specification) on a set of hop frequencies
microcontroller (or central processing unit) 330, and an
external interface 340. In the present embodiment, trans- 35 defined for that unit. Link controller 320 may leave the
standby mode to scan for page or inquiry messages, or to
ceiver 308 is coupled by a system bus 300 to a Bluetoothtransmit a page or inquiry message. When responding to a
enabled device 390 (e.g., a host device such as a computer
system or similar intelligent electronic device, a PDA, a
page message, the Bluetooth device enters the connection
state as a slave. When carrying out a successful page
printer, a fax machine, etc.). However, it is appreciated that
in another embodiment, transceiver 308 may be integrated 40 attempt, the Bluetooth device enters the connection state as
into Bluetooth-enabled device 390.
a master.
In the Bluetooth embodiment, RF module 310 is a BlueA connection between devices is made by a page message
tooth radio. The Bluetooth radio can provide: a bridge to
if the address is already known, or by an inquiry message
existing data networks, a peripheral interface, and a mechafollowed by a page message if the address is unknown. The
nism to form piconets of connected devices away from fixed 45 inquiry message enables the Bluetooth device to discover
network infrastructures (see FIG. 2).
which other Bluetooth units are in range and what their
addresses are, as well as other information such as their
Bluetooth radios operate in the ISM (Industrial, Scientific,
clocks and class-of-device. A "discoverable device" is a
Medical) band at 2.4 GHz. A frequency hop transceiver is
Bluetooth device in range that will respond to an inquiry
applied to combat interference and fading. Bluetooth uses a
packet-switching protocol based on a frequency hop scheme 50 (normally in addition to responding to a page). A discoverwith 1600 hops/second. Slots can be reserved for synchroable device scans for inquiry messages, referred to as
"inquiry scan." A "connectable device" is a Bluetooth device
nous packets. A packet nominally covers a single slot, but
in range that will respond to a page. Additional information
can be extended to cover up to five slots. Each packet is
transmitted in a different hop frequency. The entire available
is provided in conjunction with FIGS. 7A, 7B and 8, below.
frequency spectrum is used with 79 hops of one (1) MHz 55
With reference still to FIG. 3, in the present embodiment,
bandwidth, defined analogous to the IEEE (Institute of
interface 340 is for coupling transceiver 308 to BluetoothElectronic and Electrical Engineering) 802.11 standard. The
enabled device 390 in a suitable format. Transceiver 308
may be coupled by system bus 300 to Bluetooth-enabled
frequency hopping scheme is combined with fast ARQ
device 390 (e.g., a host device such as a computer system or
(Automatic Repeat Request), cyclic redundancy check
60 similar intelligent electronic device, a PDA, a printer, a fax
(CRC) and Forward Error Correction (FEC) for data.
In the present embodiment, link controller 320 is a
machine, etc.), or transceiver 308 may be integrated into
Bluetooth-enabled device 390.
hardware digital signal processor for performing baseband
processing as well as other functions such as Quality-ofIn accordance with the present invention, BluetoothService, asynchronous transfers, synchronous transfers,
enabled device 390 may be powered down (turned off) while
audio coding, and encryption (refer also to FIG. 6, below). 65 transceiver 308 continues to function, for example, in the
Link controller 320 has two major states: standby and
standby mode. Thus, with Bluetooth-enabled device 390
powered off, transceiver 308 may remain connectable. Howconnection. In addition, there are seven substates: page,

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ever, in accordance with the present invention, when Bluetooth-enabled device 390 is powered off, transceiver 308
does not remain discoverable. When Bluetooth-enabled
device 390 is powered on, then transceiver 308 is discoverable in accordance with the present invention. Additional
information is provided in conjunction with FIG. 8, below.
Continuing with reference to FIG. 3, in the present
embodiment, interface 340 runs software that allows transceiver 308 to interface with the operating system of Bluetooth-enabled device 390. In accordance with the present
invention, interface 340 may be any of a variety of physical
bus interfaces, including but not limited to a Universal Serial
Bus (USB) interface, a Personal Computer (PC) Card interface, a CardBus or Peripheral Component Interconnect
(PCI) interface, a mini-PCI interface, a Personal Computer
Memory Card International Association (PCMCIA) interface, an Industry Standard Architecture (ISA) interface, or a
RS-232 interface.
FIG. 4 is a block diagram of one embodiment of a host
device that can be used in accordance with the present
invention. In the present embodiment, the host device is a
portable computer system 400; however, it is appreciated
that the host device may be another type of intelligent
electronic device. In the Bluetooth embodiment, portable
computer system 400 is a Bluetooth-enabled device (e.g.,
device 390 of FIG. 3) coupled with a Bluetooth transceiver
308. Portable computer system 400 is also referred to as a
PDA, a portable information device (PID), a palmtop or
hand-held computer system.
Continuing with reference to FIG. 4, portable computer
system 400 includes an address/data bus 300 for communicating information, a central processor 450 coupled with the
bus 300 for processing information and instructions, a
volatile memory 410 (e.g., random access memory, RAM)
coupled with the bus 300 for storing information and
instructions for the central processor 450, and a non-volatile
memory 430 (e.g., read only memory, ROM) coupled with
the bus 300 for storing static information and instructions for
the processor 450. Portable computer system 400 also
includes an optional data storage device 490 (e.g., a memory
stick) coupled with the bus 300 for storing information and
instructions. Device 490 can be removable. Portable computer system 400 also contains a display device 440 coupled
to the bus 300 for displaying information to the computer
user.
Portable computer system 400 also includes a signal
transmitter/receiver (transceiver) device 308, which is
coupled to bus 300 for providing a wireless radio (RF)
communication link between portable computer system 400
and other wireless devices. In the Bluetooth embodiment,
transceiver 308 is compliant with the Bluetooth specification; see FIG. 3.
In the Bluetooth embodiment, in accordance with the
present invention, portable computer system 400 of FIG. 4
may be powered down (turned off) while transceiver 308
continues to function, for example, in the standby mode.
Thus, with portable computer system 400 powered off,
transceiver 308 may remain connectable. However, in accordance with the present embodiment of the present invention,
when portable computer system 400 is powered off, transceiver 308 does not remain discoverable. When portable
computer system 400 is powered on, then transceiver 308 is
discoverable in accordance with the present invention. Additional information is provided in conjunction with FIG. 8,
below.
In one embodiment, portable computer system 400
includes host interface circuitry 420 coupled to bus 300.

Host interface circuitry 420 includes an optional digital
signal processor (DSP) 422 for processing data to be transmitted or data that are received via transceiver 308. Alternatively, processor 450 can perform some or all of the
functions performed by DSP 422.
Also included in computer system 400 is an optional
alphanumeric input device 460 that, in one implementation,
is a handwriting recognition pad ("digitizer"). Alphanumeric
input device 460 can communicate information and command selections to processor 450 via bus 300. In one
implementation, alphanumeric input device 460 is a touch
screen device. Alphanumeric input device 460 is capable of
registering a position where a stylus element (not shown)
makes contact.
Portable computer system 400 also includes an optional
cursor control or directing device (on-screen cursor control
480) coupled to bus 300 for communicating user input
information and command selections to processor 450. In
one implementation, on-screen cursor control device 480 is
a touch screen device incorporated with display device 440.
On-screen cursor control device 480 is capable of registering
a position on display device 440 where a stylus element
makes contact. The display device 440 utilized with portable
computer system 400 may be a liquid crystal display (LCD)
device, a cathode ray tube (CRT), a field emission display
device (also called a fiat panel CRT), or other display device
suitable for generating graphic images and alphanumeric
characters recognizable to the user. In the preferred embodiment, display device 440 is a fiat panel display.
FIG. 5 is a block diagram showing additional features of
portable computer system 400 in accordance with one
embodiment of the present invention. User interface circuitry 540 is coupled to processor 450 via bus 300. User
interface circuitry includes hardware and software components that provide user input and output resources for
functions performed by processor 450. In the present
embodiment, user interface circuitry 540 includes a display
output 560, a display input 570, and communication interface 580.
In this embodiment, display output 560 receives digital
information representing graphical information from processor 450, and converts the information to a graphical
display, such as text and/or images, for display on display
device 440 (FIG. 4), for example. Display input 570 may
receive data inputs, such as graphical data inputs, from a
user. The graphical data inputs can be entered by the user
with a stylus element on the pressure-sensitive display
device 440 (specifically, on-screen cursor control device
480, FIG. 4) or the alphanumeric input device 460 (FIG. 4).
The communication interface 580 allows the user to enter
other types of data, such as audio or video data, or data
formatted for operation with particular applications
executed by portable computer system 400, such as calendar
data, electronic mail data, word processing, databases, and
the like. In one embodiment of the present invention, the
communication interface 580 is a serial communication port,
but could also alternatively be of any of a number of
well-known communication standards and protocols, e.g.,
parallel, SCSI (small computer system interface), Firewire
(IEEE 1394), Ethernet, etc.
Host interface circuitry 420 is coupled to processor 450
via bus 300. Host interface circuitry 420 (or link interface
circuitry or data interface circuitry) illustrates, but is not
limited to, two alternative link interface ports for establishing a wireless link to another device: an RF interface port
526 and an infrared (IR) interface port 532.

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In the present embodiment, RF circuitry 524 converts
signals to radio frequency output and accepts radio frequency input via RF interface port 526. In the Bluetooth
embodiment, RF interface port 526 is a Bluetooth transceiver 308 (FIG. 3). RF signals received by RF circuitry 524
are converted to electrical signals and relayed to RF protocol
stack 550 via connection 522.
In the present embodiment, IR circuitry 530 converts
signals into infrared output and accepts infrared input via IR
interface port 532. Infrared communication signals received
by IR circuitry 530 are converted to electrical signals that are
relayed to IR protocol stack 520 via connection 528.
Processor 450 is capable of executing RF protocol stack
550 and IR protocol stack 520. IR stack 520 implements an
IR protocol to support infrared links with other devices.
FIG. 6 is a block diagram illustrating the layers of the RF
protocol stack 550 used by a Bluetooth-enabled device such
as portable computer system 400 of FIG. 4 in accordance
with one embodiment (the Bluetooth embodiment) of the
present invention. The layers of RF protocol stack 550
include baseband (link controller) layer 320, Link Manager
Protocol (LMP) layer 620, Logical Link Control and Adaptation Protocol (L2CAP) layer 630, Telephony Control Protocol (TCS) layer 640, RFCOMM layer 650, Service Discovery Protocol (SDP) layer 660, and Object Exchange
Protocol (OBEX) layer 670.
Continuing with reference to FIG. 6, in the present
embodiment, baseband layer 320 carries out baseband protocols and other low-level link routines. LMP layer 620 is
used for link set-up, security and control. L2CAP layer 630
supports higher level protocol multiplexing, packet segmentation and reassembly, and the conveying of quality-ofservice information. TCS layer 640 defines the call control
signaling for the establishment of speech and data calls
between Bluetooth devices. RFCOMM layer 650 provides
emulation of serial ports over the L2CAP protocol 630. SDP
layer 660 provides a means for applications to discover
which services are available, and the characteristics of the
services. OBEX layer 670 enables the exchange of data
objects. Additional information is provided by "Specification of the Bluetooth System, Core," version 1.0B, dated
Dec. 1, 1999, herein incorporated by reference in its entirety.
FIG. 7Ais a data flow diagram 700a illustrating a device
discovery process for a discoverable device (responder
device 730) in accordance with one embodiment of the
present invention. In the Bluetooth embodiment, initiator
device 720 and responder device 730 are Bluetooth-enabled
devices (refer to FIGS. 3 and 4). To simplify the discussion,
the present invention is discussed for a single initiator device
and responder device; however, it is understood that the
present invention can be utilized with multiple initiator and
responder devices.
In the present embodiment, initiator device 720 sends
(broadcasts) an inquiry 740 which is intended to be received
by responder device 730. Responder device 730 must be
discoverable in order to receive inquiry 740, meaning that
responder device 730 is scanning for inquiry messages.
When responder device 730 is in discoverable mode, it sends
inquiry response 742 to initiator device 720 in response to
inquiry 740. In accordance with the present invention,
responder device 730 is in the discoverable mode when the
device is powered on (in awake mode).
With reference next to FIG. 7B illustrating data flow
diagram 700b, responder device 730 is non-discoverable
(not in the discoverable mode) when the device is powered
off (in sleep mode or standby). In one embodiment, when
non-discoverable, responder device 730 may not be scan-

ning for inquiry messages 740. In another embodiment,
when non-discoverable, responder device 730 may scan for
inquiry messages 740, but will not send an inquiry response
742 in response to an inquiry message 740.
With reference to FIGS. 7A and 7B, responder device 730
is connectable when it is in either discoverable mode or in
non-discoverable mode. That is, responder device 730 can
receive a directed message (a message that specifies
responder device 730 by its name and/or address, such as
page 744) from initiator device 720. In addition, when
connectable, responder device 730 can respond to page 744
(e.g., page response 746).
FIG. 8 is a flowchart of the steps for managing a device
discovery process 800 in accordance with one embodiment
of the present invention. Process 800 is implemented as
computer-readable program instructions stored in a memory
unit (e.g., ROM non-volatile 430 of FIG. 4; specifically, RF
protocol stack 550 of FIG. 5) and executed by a processor
(e.g., processor 450 or DSP 422 of FIG. 4). In the Bluetooth
embodiment, portable computer system 400 is Bluetoothenabled.
In step 810 of FIG. 8, with reference also to FIGS. 7A and
7B, inquiry message 740 is broadcast by initiator device
720.
In step 820 of FIG. 8, also with reference to FIGS. 7A and
7B, responder device 730 can be either powered on (awake)
or powered off (asleep). If awake, process 800 proceeds to
step 830; if asleep, process 800 proceeds to step 850.
In step 830 of FIG. 8, with reference also to FIG. 7A, in
accordance with the present invention, responder device 730
is in discoverable mode when it is powered on (awake). In
one embodiment, when the user turns on responder device
730, the device is automatically placed into the discoverable
mode. In the Bluetooth embodiment, transceiver 308 (FIGS.
3, 4 and 5) is in discoverable mode. In discoverable mode,
transceiver 308 is scanning for and can respond to inquiry
740.
In step 840 of FIG. 8, and with reference to FIG. 7A, in
accordance with the present invention, with responder
device 730 in discoverable mode, responder device 730
sends inquiry response 742 to initiator device 720.
In step 850 of FIG. 8, with reference also to FIG. 7B, in
accordance with the present invention, responder device 730
is in non-discoverable mode when it is powered off ( asleep).
In one embodiment, when the user turns off responder
device 730, the device is automatically placed into the
non-discoverable mode. In the Bluetooth embodiment,
transceiver 308 (FIGS. 3, 4 and 5) is in non-discoverable
mode. In one embodiment, when in non-discoverable mode,
transceiver 308 does not scan for inquiry message 740. In
another embodiment, when in non-discoverable mode,
transceiver 308 may scan for inquiry message 740, but will
not respond to inquiry message 740 when such a message is
detected.
In step 860 of FIG. 8, with reference also to FIG. 7B, in
accordance with the present invention, with responder
device 730 in non-discoverable mode, responder device 730
does not send inquiry response 742 to initiator device 720.
Therefore, in accordance with the present invention,
responder device 730 is automatically made discoverable or
non-discoverable depending on whether the device is powered on or powered off, as described above. Accordingly, the
device discovery process can be managed by the user in a
way that is both user-friendly and intuitively understood by
the user. For example, when the user turns responder device
730 on, it automatically is placed into discoverable mode,
and turning the device off automatically places responder

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device 730 into non-discoverable mode. In essence, the
coverable mode. In the discoverable mode, responder device
on/off switch of responder device 730 also functions as the
730 receives and responds to all broadcast messages sent
mechanism by which the user selects either discoverable or
from other devices within range, whereas in the connectable
mode responder device 730 only receives and responds to
non-discoverable mode. Thus, a user can manage the device
discovery process according to a usage model already under- 5 directed messages. Because there are fewer directed messtood by the user.
sages than broadcast messages, less power will be consumed
In accordance with the present invention, responder
receiving and responding to directed messages relative to the
device 730 is in discoverable mode for a reduced period of
power consumed receiving and responding to broadcast
messages.
time, thereby conserving power (battery) resources. As such,
In summary, the present invention provides a userresponder device 730 will also respond to fewer inquiries 10
740, which in turn will reduce the number of pages 744 and
friendly system and method for managing the Bluetooth
device discovery process. The present invention also propage responses 746. Consequently, responder device 730
and initiator device 720 will exchange fewer messages,
vides a system and method can reduce the burden on the
further conserving battery resources for responder device
limited power resources available to many types of Blue730 and also conserving the battery resources of initiator 15 tooth devices. In addition, the present invention provides a
system and method that can be implemented in Bluetoothdevice 720. Fewer messages will also improve the efficiency
enabled devices, that is consistent with the Bluetooth speciof the Bluetooth device discovery process, because fewer
fication, and that can be incorporated into legacy Bluetooth
collisions between messages would be expected, and theredevices.
fore the frequency at which messages have to be retransThe preferred embodiment of the present invention,
mitted would be reduced. Furthermore, the device discovery 20
power-conserving intuitive device discovery technique in a
process will be simplified for users. For example, owing to
Bluetooth environment, is thus described. While the present
the reduction in pages 744 and page responses 746 attribinvention has been described in particular embodiments, it
utable to the reduction in inquiry responses 742, the number
should be appreciated that the present invention should not
of name requests and name request responses will also be
reduced, and hence the number of user-friendly names 25 be construed as limited by such embodiments, but rather
construed according to the following claims.
displayed to users as part of the name discovery process will
What is claimed is:
be reduced.
1. In a responder device having a transceiver for wireless
Additionally, the present invention can be implemented
communication, a method for managing responses to signals
consistent with and within the framework of the Bluetooth
specification. As such, Bluetooth-enabled devices imple- 30 received from initiator devices, said method comprising:
menting the present invention remain compatible with
automatically setting said responder device to discoverlegacy Bluetooth-enabled currently being used. Moreover,
able mode when said responder device enters awake
the present invention can also be incorporated into legacy
mode, wherein said responder device in said discoverBluetooth devices, for example, by installing appropriate
able mode scans for and responds to broadcast wireless
program instructions.
35
signals that are broadcast by initiator devices;
With reference again to FIG. 8 and with reference also to
automatically setting said responder device to non-disFIGS. 7A and 7B, in step 870, responder device 730 is
coverable mode when said responder device enters
connectable when it is in either discoverable mode or in
standby mode, wherein said responder device in said
non-discoverable mode does not scan for and does not
non-discoverable mode. That is, in accordance with the
respond to broadcast wireless signals that are broadcast
present invention, responder device 730 can receive a 40
by initiator devices, and wherein said standby mode is
directed message (e.g., page 744) from initiator device 720
a power-conserving mode relative to said awake mode;
whether responder device is in the discoverable mode or the
non-discoverable mode.
and
automatically setting said responder device to connectFor example, at some earlier point in time when responder
able mode with said responder device in either said
device 730 was in discoverable mode, it may have provided 45
awake mode or said standby mode, wherein said
its address (device access code) to initiator device 720.
responder device in said connectable mode receives
Initiator device can then use that address to send a directed
and responds to directed wireless signals from initiator
message to responder device 730 (a page 744 instead of a
devices, wherein directed wireless signals specifically
broadcast message such as inquiry 740). Thus, messages
identify said responder device.
from devices that have previously been made known to 50
2. The method as recited in claim 1 further comprising:
responder device 730 can be received by responder device
730 whether it is discoverable or non-discoverable. The
receiving at said responder device a first wireless signal
broadcast by an initiator device;
present invention therefore provides another advantage by,
sending a second wireless signal in response to said first
in essence, screening messages from devices that are
wireless signal when said responder device is in said
unknown to responder device 730 as well as the user. 55
discoverable mode, wherein said second wireless signal
Because the user controls when responder device 730 is and
is to be received by said initiator device; and
is not discoverable, the user also controls access to
disregarding said first wireless signal when said responder
responder device 730 by unknown devices. That is, an
device is in said non-discoverable mode.
unknown device cannot make contact with responder device
3. The method as recited in claim 2 further comprising:
730 without the user's knowledge and permission.
60
receiving a third wireless signal from said initiator device,
In step 880 of FIG. 8, with reference to FIGS. 7Aand 7B,
wherein said third wireless signal is a directed signal
responder device 730 can respond to page 744 in page
sent to said responder device in response to said second
response 746. In addition, initiator device 720 and responder
wireless signal.
device 730 can establish a persistent connection. Therefore,
even if responder device 730 is non-discoverable in accor- 65
4. The method as recited in claim 3 wherein said
responder device is in a connectable mode at all times said
dance with the present invention, it will remain connectable.
responder device is powered on.
The connectable mode consumes less power than the dis-

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5. The method as recited in claim 2 wherein said initiator
17. The method as recited in claim 10 wherein said
device and said responder device are Bluetooth-enabled
responder device is a portable computer system.
devices.
18. A responder device comprising:
6. The method as recited in claim 5 wherein said first
a bus;
wireless signal is an inquiry message requesting an address 5
a wireless transceiver unit coupled to said bus and for
for said responder device.
communicating with initiator devices; and
7. The method as recited in claim 6 wherein said second
a processor coupled to said bus, said processor for perwireless signal comprises said address for said responder
forming a method for managing responses to signals
received from said initiator devices, said method comdevice.
prising:
8. The method as recited in claim 7 wherein said third 10
wireless signal is a page message directed to said address
automatically setting said responder device to discovand comprising a request for a name of said responder
erable mode when said responder device enters
device.
awake mode, wherein said responder device in said
9. The method as recited in claim 1 wherein said
discoverable mode scans for and responds to broad15
responder device is a portable computer system.
cast wireless signals that are broadcast by initiator
devices;
10. In a responder device having a transceiver for wireless
automatically setting said responder device to noncommunication, a method for managing responses to signals
received from initiator devices, said method comprising:
discoverable mode when said responder device
enters standby mode, wherein said responder device
receiving at said responder device a first wireless signal
in said non-discoverable mode does not scan for and
broadcast by an initiator device, wherein said first 20
wireless signal is a broadcast signal also received by
does not respond to broadcast wireless signals that
multiple responder devices within range of said initiaare broadcast by initiator devices, and wherein said
tor device;
standby mode is a power-conserving mode relative
automatically entering a discoverable mode when said
to said awake mode; and
responder device enters awake mode, wherein said 25
automatically setting said responder device to connectresponder device in said discoverable mode sends a
able mode with said responder device in either said
second wireless signal in response to said first wireless
awake mode or said standby mode, wherein said
signal, wherein said second wireless signal is to be
responder device in said connectable mode receives
received by said initiator device;
and responds to directed wireless signals from iniautomatically entering a non-discoverable mode when 30
tiator devices, wherein directed wireless signals spesaid responder device enters standby mode, wherein
cifically identify said responder device.
said responder device in said non-discoverable mode
19. The responder device of claim 18 wherein said
method further comprises:
receives but does not send a response to said first
receiving at said responder device a first wireless signal
wireless signal, and wherein said standby mode is a
broadcast by an initiator device;
power-conserving mode relative to said awake mode; 35
sending a second wireless signal in response to said first
and
wireless signal when said responder device is in said
automatically entering a connectable mode with said
discoverable mode, wherein said second wireless signal
responder device in either said awake mode or said
is to be received by said initiator device; and
standby mode, wherein said responder device in said
disregarding said first wireless signal when said responder
connectable mode receives and responds to a directed 40
device is in said non-discoverable mode.
wireless signal from initiator device, wherein said
20. The responder device of claim 19 wherein said
directed wireless signal specifically identifies said
method further comprises:
responder device so that only said responder device and
receiving a third wireless signal from said initiator device,
not any other of said multiple responder devices within
said range of said initiator device receives said directed 45
wherein said third wireless signal is a directed signal
wireless signal.
sent to said responder device in response to said second
11. The method as recited in claim 10 further comprising:
wireless signal.
21. The responder device of claim 20 wherein said
receiving a third wireless signal from said initiator device,
responder device is in a connectable mode at all times said
wherein said third wireless signal is a directed signal
sent to said responder device in response to said second 50 responder device is powered on.
wireless signal.
22. The responder device of claim 20 wherein said
12. The method as recited in claim 11 wherein said
initiator device and said responder device are Bluetoothresponder device is in a connectable mode at all times said
enabled devices.
responder device is powered on.
23. The responder device of claim 22 wherein said first
13. The method as recited in claim 11 wherein said 55 wireless signal is an inquiry message requesting an address
initiator device and said responder device are Bluetoothfor said responder device.
enabled devices.
24. The responder device of claim 23 wherein said second
wireless signal comprises said address for said responder
14. The method as recited in claim 13 wherein said first
device.
wireless signal is an inquiry message requesting an address
60
25. The responder device of claim 24 wherein said third
for said responder device.
wireless signal is a page message directed to said address
15. The method as recited in claim 13 wherein said second
and comprising a request for a name of said responder
wireless signal comprises said address for said responder
device.
device.
26. The responder device of claim 18 wherein said
16. The method as recited in claim 15 wherein said third
wireless signal is a page message directed to said address 65 responder device is a portable computer system.
and comprising a request for a name of said responder
device.
* * * * *