8004368
`
`June 10, 2019
`
`THIS IS TO CERTIFY THAT ANNEXED IS A TRUE COPY FROM THE
`RECORDS OF THIS OFFICE OF THE FILE WRAPPER AND CONTENTS
`OF:
`
`APPLICATION NUMBER: 10/737,029
`FILING DATE: December 16, 2003
`PATENT NUMBER: 7589642
`ISSUE DATE: September 15, 2009
`
`0001
`
`Roku EX1002
`U.S. Patent No. 7,589,642
`
`

`

`Attorney Docket No. ,
`
`UTILITY PATENT APPLICATION TRANSMITTAL ,
`1
`New Non rovisional A lication Under 37 CFR ~ 1.53 b
`
`‘ ZIL-568
`_
`,
`
` Old'80617091 Attached for filing is a patent application identified as follows:
`
`TO THE COMMISSIONER FOR PATENTS:
`
`Inventor: Daniel SauFu Mui
`Assignee: ZiLOG, Inc.
`Title:
`“RELAYING KEY CODE SIGNALS THROUGH A REMOTE CONTROL DEVICE”
`
`(X)
`(
`)
`
`Original Patent Application;
`Continuing Application (prior applications not abandoned).
`(
`) Continuation
`(
`) Divisional
`(
`) Continuation—i—n-part (CIP) of;
`The specification contains a statement claiming the benefit of 35 USC § 119(e);
`)
`(
`and including attachments as noted below:
`
`O
`I— O?
`:8
`:5 I?)|\
`
`x This transmittal letter (in duplicate)
`21 Pages of Specification
`6 Pages of Claims (including 24 numbered claims)
`1 Page Abstract
`4 Pages of Drawings (formal)
`2 Pages Declaration/Power of Attorney (signed)
`
`E31]?
`1 Page Assignment (signed)
`1 Page Recordation Cover Sheet N
`1 Page Request not to Publish
`x A check for filing fee ($968.00)
`x A return—receipt postcard
`
`
`
`Total Claims
`Independent Claims
`
`NO. FILED
`
`4
`
`$86.00
`
`._—
`Reg. No. 53,736 Mail Stop Patent Application
`
`I hereby certify that this is being deposited with the
`
`US Postal Service as “Express Mail Post Office to
`Addressee” service under 37 CFR § 1 10 on the date By'
`mdlcated below andIS addressed to;
`
`: l
`f
`.
`EZ
`%
`Darien K. Wallace, Attorney for Applicant
`
`Respectfully submitted,
`
`Commissioner for Patents
`PO. Box 1450
`Alexandria, VA 22313—1450
`
`~ 1/ ’
`_
`By:
`'
`Typed Name Dane“ K- Wallace
`
`Express Mail Label No.: ER 452602378 US
`
`Date of Deposit: December 16, 2003
`
`Date: @6404” /‘ 2403
`
`
`Correspondence Address:
`Silicon Edge Law Group LLP
`6601 K011 Center Parkway, Suite 245
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`Phone: (925) 621-2121
`Fax:
`(925) 621'21 19
`
`0002
`
`0002
`
`

`

`PTO/SB/35 (1100)
`Approved for use through 10/31/2002. OMB 0651-0031
`U.S. Patent and Trademark Office; U. S. DEPARTMENT OF COMMERCE
`Under the Papemork Reduction Act of 1995, no persons are required to respond to a collection of information unless it displays a valid OMB control number.
`
`REQUEST AND CERTIFICATION
`
`First Named Inventor Daniel SauFu Mui
`
`U NDER
`35 UWSC 122(b)(2)(B)(i)
`
`Title
`"Relaying Key Code Signals Through a Remote Control Device"
`Atty Docket Number ZlL-568
`
`I hereby certify that the invention disclosed in the attached application has not and will not
`be the subject of an application filed in another country, or under a multilateral agreement,
`that requires publication at eighteen months after filing.
`I hereby request that the attached
`application not be published under 35 U.S.C. 122(b).
`
`
`
`December 16, 2003
`Date
`
`‘ /é
`Signature
`
`Darien K. Wallace
`
`Typed or printed name
`
`This request must be signed in compliance with 37 CFR 1.33(b) and submitted with the
`application upon filing.
`
`If applicant rescinds a
`Applicant may rescind this nonpublication request at any time.
`request that an application not be published under 35 U.S.C. 122(b). the application will be
`scheduled for publication at eighteen months from the earliest claimed filing date for which a
`benefit is claimed.
`
`If applicant subsequently files an application directed to the invention disclosed in the
`attached application in another country, or under a multilateral international agreement, that
`requires publication of applications eighteen months after filing, the applicant must notify the
`United States Patent and Trademark Office of such filing within forty-five (45) days after the
`date of the filing of such foreign or international application. Failure to do so will result in
`abandonment of this application (35 U.S.C. 122(b)(2)(B)(iii)).
`
`Burden Hour Statement: This collection of information is required by 37 CFR 1.213(a). The information is used by the public to request that an application not be
`published under 35 U.S.C. 122(b) (and the PTO to process that request). Confidentiality is governed by 35 U.S.C. 122 and 37 CFR 1.14. This form is estimated
`to take 6 minutes to complete. This time will vary depending upon the needs of the individual case. Any comments on the amount of time you are required to
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`COMPLETED FORMS TO THIS ADDRESS. SEND TO: Assistant Commissioner for Patents. Washington, DC 20231.
`
`0003
`
`0003
`
`

`

`ZIL-568
`
`PATENT
`
`This correspondence is being deposited with the United States Postal Service as
`Express Mail addressed to: Mail Stop Patent Application, Commissioner for Patents.
`PO. Box 1450, Alexandria, VA 22313-1450, on Mag (é 2&0 3 ,
`Express Mail Receipt No. ER 452602378 US.
`
`RELAYING KEY CODE SIGNALS THROUGH A REMOTE
`CONTROL DEVICE
`
`Daniel SauFu Mui
`
`TECHNICAL FIELD
`
`[0001] The present
`
`invention relates generally to remote
`
`control devices and, more specifically,
`
`to relaying key
`
`code signals through a remote control device to operate an
`
`electronic consumer device.
`
`BAC KGROUND
`
`[0002] Most households today possess multiple types of
`
`electronic consumer devices, such as televisions, stereo
`
`radios, digital video disk players, video cassette
`
`recorders, set—top cable television boxes and set—top
`
`satellite boxes. Manufacturers of such electronic devices
`
`typically supply a remote control device along with each
`
`electronic device.
`
`It is,
`
`therefore, common for a consumer
`
`who has multiple electronic devices to have multiple remote
`
`control devices.
`
`[0003] A remote control device typically controls a
`
`selected electronic consumer device by transmitting
`
`infrared key code signals to the selected electronic
`
`consumer device.
`
`The infrared signals contain key codes of
`
`a codeset associated with the selected electronic consumer
`
`device.
`
`Each key code corresponds to a function of the
`
`selected electronic device, such as power on, power off,
`
`volume up, volume down, play, stop, select, channel up,
`
`channel down, etc.
`
`In order to avoid the situation where a
`
`0004
`
`0004
`
`

`

`ZIL-568
`
`PATENT
`
`remote control device unintentionally operates an
`
`electronic consumer device that is associated with a
`
`different remote control device, manufacturers sometimes
`
`use distinct codesets for the communication between various
`
`electronic consumer devices and their associated remote
`
`control devices.
`
`The codesets can differ from each other
`
`not only by the bit patterns assigned to various functions
`
`of the associated electronic consumer device, but also by
`
`the timing information that describes how the key codes
`
`should be modulated onto carrier signals to generate key
`
`code signals.
`
`[0004] Consumers may find it inconvenient to operate their
`
`electronic devices using multiple remote control devices.
`
`Thus, a consumer may wish to operate multiple electronic
`
`consumer devices using a single remote control device.
`
`A
`
`single remote control device can store many codesets so
`
`that the remote control device can control a corresponding
`
`large number of different electronic consumer devices.
`
`There are, however,
`
`thousands of codesets in use in
`
`electronic consumer devices today. Manufacturers of remote
`
`control devices, however, may wish to limit the memory on
`
`their remote control devices to a size that is insufficient
`
`to store the thousands of existing codesets.
`
`[0005] A system is sought for enabling a remote control
`
`device to control a selected one of multiple different
`
`electronic consumer devices without requiring the codeset
`
`associated with the selected electronic consumer device to
`
`be stored on the remote control device.
`
`SUMMARY
`
`[0006] A system for relaying a key code through a remote
`
`control device to an electronic consumer device allows the
`
`0005
`
`0005
`
`

`

`ZIL-568
`
`PATENT
`
`electronic consumer device to be controlled without storing
`
`the associated codeset on the remote control device. Upon
`
`receiving a keystroke indicator signal from a remote
`
`control device, a key code generator device, such as a set-
`
`top box,
`
`identifies the particular codeset usable to
`
`communicate with the selected electronic consumer device.
`
`The keystroke indicator signal contains an indication of a
`
`key on the remote control device that was pressed, which
`
`corresponds to a function of the selected electronic
`
`consumer device. Using the identified codeset and the
`
`indication of the pressed key,
`
`the key code generator
`
`device generates a key code and modulates that key code
`
`onto a radio frequency carrier signal,
`
`thereby generating a
`
`first key code signal.
`
`The remote control device receives
`
`the first key code signal from the key code generator
`
`device and modulates the key code onto an infrared
`
`frequency carrier signal,
`
`thereby generating a second key
`
`code signal.
`
`The remote control device relays the key code
`
`to the selected electronic consumer device in the second
`
`key code signal.
`
`The key code causes the selected
`
`electronic consumer device to perform the desired function.
`
`The key code is not stored on the remote control device in
`
`a permanent manner, but rather then key code is relayed
`
`through the remote control device.
`
`[0007]
`
`In another embodiment, a third key code signal
`
`(which may,
`
`for example, be a radio frequency signal)
`
`is
`
`communicated directly from the key code generator device to
`
`an electronic consumer device.
`
`A key code contained in the
`
`third key code signal causes the electronic consumer device
`
`to perform a desired function.
`
`[0008]
`
`In yet another embodiment,
`
`the system automatically
`
`determines which codeset is usable to communicate with a
`
`0006
`
`0006
`
`

`

`ZIL-568
`
`PATENT
`
`selected electronic consumer device.
`
`The key code
`
`generator device sends key codes for one particular
`
`function from among a series of codesets one-by—one to the
`
`selected electronic consumer device. When the key code
`
`from one of the codesets causes the electronic consumer
`
`device to perform the desired function, electromagnetic
`
`noise is introduced into electrical power wiring through
`
`which both the electronic consumer device and the key code
`
`generator device receive power. When the key code
`
`generator device detects this noise on the electrical power
`
`wiring,
`
`the key code generator device identifies the
`
`codeset corresponding to the last transmitted key code to
`
`be the codeset usable to communicate with the selected
`
`electronic consumer device.
`
`[0009] Other embodiments and advantages are described in
`
`the detailed description below. This summary does not
`
`purport to define the invention.
`
`The invention is defined
`
`by the claims.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0010] The accompanying drawings, where like numerals
`
`indicate like components,
`
`illustrate embodiments of the
`
`invention.
`
`[0011] Figure 1 is a schematic diagram of a system for
`
`relaying key code signals through a remote control device.
`
`[0012] Figure 2 is a flowchart of a method for relaying key
`
`code signals through a remote control device.
`
`[0013] Figure 3 is an illustration of a key code
`
`transmitted within a key code signal.
`
`[0014] Figure 4 is a waveform diagram of a first example of
`
`a key code signal
`
`transmitted by a remote control device in
`
`the system of figure 1.
`
`0007
`
`0007
`
`

`

`ZIL-568
`
`PATENT
`
`[0015] Figure 5 is a waveform diagram of a second example
`
`of a key code signal transmitted by a remote control device
`
`in the system of figure 1.
`
`[0016] Figure 6A is an illustration of a modulated digital
`
`zero and digital one within the key code signal of figure
`
`5.
`
`[0017] Figure 6B is a more detailed illustration of a mark
`
`of a modulated digital zero within the key code signal of
`
`figure 5.
`
`DETAILED DESCRIPTION
`
`[0018] Reference will now be made in detail to some
`
`embodiments of the invention, examples of which are
`
`illustrated in the accompanying drawings.
`
`[0019] Figure 1 is a diagram of a system 10 for relaying a
`
`key code through a remote control device 11 to an
`
`electronic consumer device in accordance with the present
`
`invention.
`
`Figure 2 is a flowchart that illustrates a
`
`method of operation of system 10.
`
`System 10 includes a key
`
`code generator device 12,
`
`remote control device 11, a first
`
`electronic consumer device 13 and a second electronic
`
`consumer device 14.
`
`In this example, second electronic
`
`consumer device 14 is a television set.
`
`[0020]
`
`In a first step (step 100), key code generator
`
`device 12 determines the appropriate codeset that controls
`
`the type, brand and model of the particular electronic
`
`consumer device that is to be controlled.
`
`A user uses
`
`remote control device 11 to respond to an on-screen display
`
`15 on the screen of television set 14 to step through a
`
`sequence of menu screens to identify the codeset
`
`corresponding to the device that is to be controlled.
`
`The
`
`user does this by identifying, on on-screen display 15,
`
`the
`
`0008
`
`0008
`
`

`

`ZIL—568
`
`PATENT
`
`type, brand and model of the particular electronic consumer
`
`device.
`
`In this example,
`
`the user is identifying first
`
`electronic consumer device 13, which is a Video cassette
`
`recorder (VCR) manufactured by Sony with model number 8000.
`
`In figure 1,
`
`the user is identifying the device type by
`
`highlighting the choice “VCR" on the on—screen display.
`
`In another example, subsequent to controlling VCR 13,
`
`the
`
`user may wish to control television set 14, which is a
`
`“Gold” model manufactured by RCA.
`
`In that case,
`
`the user
`
`begins identifying television set 14 by highlighting the
`
`choice “TV”.
`
`[0021]
`
`In the present example, key code generator device 12
`
`is a set—top box. Key code generator device 12 generates
`
`the on—screen displays and communicates with television set
`
`14 such that key code generator device 12 identifies one of
`
`a plurality of codesets that corresponds to one of the
`
`electronic consumer devices identified by the user, such as
`
`VCR 13 or television set 14.
`
`System 10 uses the
`
`appropriate codeset to enable remote control device 11 to
`
`communicate with VCR 13 and television set 14.
`
`[0022] Next
`
`(step 101),
`
`the user presses a key on remote
`
`control device 11. This key is associated with a function
`that the user wants performed by an electronic consumer
`
`device.
`
`For example,
`
`the function may be to turn on the
`
`power of VCR 13. When the user presses the “VCR power-on"
`
`key on remote control device 11,
`
`remote control device 11
`
`transmits a keystroke indicator signal 16 from a radio
`
`frequency (RF)
`
`transmitter 17 on remote control device 11.
`
`Alternatively,
`
`two or more keys on remote control device 11
`
`may be associated with a single function, such as turning
`
`on the power of VCR 13.
`
`In that case,
`
`the user presses a
`
`“VCR” key and then a “power—on” key to cause remote control
`
`0009
`
`0009
`
`

`

`ZIL-568
`
`PATENT
`
`device 11 to transmit keystroke indicator signal 16.
`
`Keystroke indicator signal 16 is transmitted as a signal in
`
`a radio frequency band to an RF receiver 18 on key code
`
`generator device 12.
`
`[0023] There are multiple forms in which an indication of
`
`the pressed key, as well as the identity of the electronic
`
`consumer device that is to perform the associated function,
`
`can be communicated in keystroke indicator signal 16 from
`
`remote control device 11 to key code generator device 12.
`
`In one embodiment,
`
`the indication of the pressed key is a
`
`key code comprised of a standardized system code and
`
`standardized key data.
`
`In the present example,
`
`the
`
`standardized system code identifies the type of electronic
`
`consumer device that is to be controlled, such as a TV, a
`
`VCR, a DVD player, a stereo amplifier, a satellite receiver
`
`or a cable receiver.
`
`The standardized system code and key
`
`data are part of a commonly used codeset that is stored on
`
`remote control device 11. Remote control device 11 uses
`
`any one of a number of commonly used modulation techniques
`
`to modulate the system code and key data to form keystroke
`
`indicator signal 16.
`
`For example, a microcontroller on
`
`remote control device 11 uses timing information associated
`
`with the commonly used codeset to generate a pulse width
`
`modulated keystroke indicator signal 16.
`
`[0024]
`
`In another embodiment,
`
`the indication of the pressed
`
`key includes a proprietary identification code identifying
`
`the pressed key, as well as a proprietary identification
`
`code corresponding to the type of the electronic consumer
`
`device that is to be controlled.
`
`The proprietary
`
`identification codes are understood by key code generator
`
`device 12, but are not standardized codes that are
`
`understood by electronic consumer devices. Remote control
`
`0010
`
`0010
`
`

`

`ZIL-568
`
`PATENT
`
`device 11 uses any one of a number of commonly used
`
`modulation techniques to modulate the proprietary
`
`identification codes onto keystroke indicator signal 16.
`
`[0025] Whether remote control device 11 communicates with
`
`key code generator device 12 through a standardized codeset
`
`or through proprietary identification codes, codes may be
`
`included that do not correspond to pressed keys or
`
`functions that are to be performed on electronic consumer
`
`devices.
`
`For example,
`
`in response to receiving any signal
`
`from remote control device 11, key code generator device 12
`
`may return a code to remote control device 11 causing a
`
`light emitting diode (LED) display on remote control device
`
`11 to turn on.
`
`[0026] Next
`
`(step 102), key code generator device 12
`
`determines which key code of the codeset previously
`
`identified in step 100 corresponds to the pressed key.
`
`[0027] Figure 3 illustrates one example of a key code from
`
`a commonly used codeset.
`
`The key code is comprised of a
`
`standardized system code and standardized key data. Both
`
`the system code and the key data are digital values.
`
`The
`
`12—bit key code includes a 4-bit system code [0101] and 8—
`
`bit key data [00011100].
`
`In the present example,
`
`the key
`
`code is the key code in the identified codeset that
`
`corresponds to the “VCR power-on" key of remote control
`
`device 11.
`
`[0028] Next
`
`(step 103), key code generator device 12
`
`modulates the key code for the power—on function of VCR 13
`
`onto a first carrier signal,
`
`thereby generating a first key
`
`code signal 19.
`
`In this example,
`
`the first carrier signal
`
`is an RF signal. An RF signal for purposes of this patent
`
`document is an electromagnetic signal having a frequency
`
`between thirty hertz and three hundred gigahertz.
`
`8
`
`0011
`
`0011
`
`

`

`ZIL-568
`
`PATENT
`
`[0029] Figure 4 and figure 5 illustrate key code signal 19
`
`in two specific embodiments.
`
`In both embodiments,
`
`the key
`
`code is transmitted as a stream of digital values
`
`010100011100, where the system code is transmitted first
`
`immediately followed by the key data without any place
`
`holders between them.
`
`The standardized system code
`
`determined in step 102 need not identify the brand or model
`
`of VCR 13, but only the fact that first electronic consumer
`
`device 13 is a VCR.
`
`The key code is modulated in step 103
`
`using timing information associated with the codeset for
`
`VCR 13. Thus,
`
`the particular brand and model of VCR 13 is
`
`able to understand the key code modulated using the
`
`appropriate timing information.
`
`[0030]
`
`In the embodiment of figure 4, key code signal 19 is
`
`a 15-bit binary transmission whose bit pattern appears as a
`
`universal asynchronous receiver and-transmitter (UART)
`
`type
`
`communication.
`
`The binary transmission begins with a start
`
`bit and ends with a parity bit and a stop bit.
`
`The parity
`
`bit is calculated based on the 12—bit key code within the
`
`binary transmission.
`
`In this example,
`
`the value of the
`
`parity bit is a digital zero.
`
`An intermediary signal is
`
`transmitted over the first carrier signal at an
`
`intermediary frequency (for example, 100 kHz)
`
`to
`
`communicate a digital one.
`
`The absence of the intermediary
`
`signal indicates a digital zero.
`
`The intermediary signal
`
`has a lower frequency than the first carrier signal.
`
`[0031]
`
`In the embodiment of figure 5,
`
`the 12-bit key code
`
`is modulated onto key code signal 19 using pulse width
`
`modulation. Digital ones and zeros are characterized by
`
`pairs of marks and spaces.
`
`The period between successive
`
`leading edges of the bursts in a mark is the period of an
`
`0012
`
`0012
`
`

`

`ZIL-568
`
`PATENT
`
`intermediary signal.
`
`The intermediary signal has an
`
`’intermediary frequency.
`
`In a space,
`
`there are no bursts.
`
`[0032] Figure 6A shows a digital zero and a digital one in
`
`key code signal 19 of figure 5 in more detail.
`
`A
`
`“mark/space” pair represents a digital zero and another
`
`“mark/space” pair represents a digital one.
`
`The marks and
`
`spaces of each pair have predetermined lengths.
`
`In the
`
`embodiment of figure 5,
`
`the mark length of a digital zero
`
`is 490 microseconds, and the mark length of a digital one
`
`is 3940 microseconds.
`
`The space length of a digital zero
`
`is 950 microseconds, and the space length of a digital one
`
`is 2000 microseconds.
`
`[0033] Figure 6B shows the bursts of the first carrier
`
`signal that comprise the intermediary signal in more
`
`detail.
`
`In the embodiment of figure 5,
`
`the bursts that
`
`comprise the intermediary signal occur every ten
`
`microseconds, resulting in an intermediary frequency of 100
`
`kilohertz.
`
`The duty cycle of the intermediary signal is
`
`characterized by an “on time” of four microseconds and an
`
`“off time” of six microseconds. There are forty-nine
`
`bursts of the carrier signal within each mark length of 490
`
`microseconds.
`
`[0034] Timing information other than that shown in the
`
`embodiment of figure 5 can also be used.
`
`For example, one
`
`common form of pulse width modulation uses an intermediary
`
`signal having a frequency of about 38.5 kilohertz.
`
`Each
`
`period of the intermediary signal has an “on time" of ten
`
`microseconds and an “off time" of sixteen microseconds.
`
`If
`
`such an intermediary signal were used to generate a 490
`
`microsecond mark length of a digital zero shown in figure
`
`6A,
`
`there would be 19 bursts of the intermediary signal
`
`in
`
`the mark. Similarly, if such an intermediary signal were
`
`10
`
`0013
`
`0013
`
`

`

`ZIL-568
`
`PATENT
`
`used to generate a 3940 microsecond mark length of a
`
`digital one shown in figure 6A,
`
`there would be 151 bursts
`
`of the intermediary signal in the mark.
`
`[0035] Next
`
`(step 104), an RF transmitter 20 of key code
`
`generator device 12 transmits first key code signal 19 in
`
`the form of an RF transmission to an RF receiver 21 on
`
`remote control device 11.
`
`[0036] Next
`
`(step 105),
`
`remote control device 11 receives
`
`first key code signal 19 and relays the key code
`
`communicated by first key code signal 19 to VCR 13 in the
`
`form of a second key code signal 22. Remote control device
`
`11 is a slave to key code generator device 12. Remote
`
`control device 11 relays the key code by receiving first
`
`key code signal 19 in RF form and translating the
`
`communicated key code so that the key code is modulated
`
`onto a second carrier signal resulting in second key code
`
`signal 22.
`
`In this example,
`
`the second carrier signal is
`
`an infrared signal with a frequency in the range between
`
`three hundred gigahertz and three hundred terahertz.
`
`Second key code signal 22 is transmitted by an IR
`
`transmitter 23 on remote control device 11 to VCR 13.
`
`In
`
`the embodiment of figure 5, key code signal 19 is converted
`
`into key code signal 22 by forming the bursts of the
`
`intermediary signal using the second carrier signal with an
`
`infrared frequency in the place of the first carrier signal
`
`with a radio frequency.
`
`For both key code signal 19 and
`
`key code signal 22, digital ones and digital zeros are
`
`modulated using the same timing for “mark/space” pairs.
`
`The waveform diagram of key code signal 22 appears the same
`
`as the waveform diagram shown in figure 5 for key code
`
`signal 19; only the frequency of the carrier signal that
`
`forms the bursts is different.
`
`11
`
`0014
`
`0014
`
`

`

`ZIL-568
`
`PATENT
`
`[0037] Next
`
`(step 106), second key code signal 22 is
`
`received onto electronic consumer device (VCR)
`
`13 by an IR
`
`receiver 24.
`
`[0038]
`
`Next
`
`(step 107),
`
`IR receiver 24 on VCR 13 recovers
`
`the key code from second key code signal 22.
`
`VCR 13 is
`
`thereby instructed to perform the function desired by the
`
`user.
`
`In this example,
`
`the function is to power on VCR 13.
`
`Other key codes, however, correspond to other functions,
`
`such as power off, channel advance, channel back, volume
`
`up, volume down, cursor up, cursor down, cursor right,
`
`cursor left, select, play, record, stop,
`
`forward,
`
`rewind
`
`and pause.
`
`[0039]
`
`In a second example, an electronic consumer device
`
`is controlled by an RF key code signal transmitted from key
`
`code generator device 12.
`
`Subsequent to controlling VCR
`
`13,
`
`the user wishes to control second electronic consumer
`
`device 14, which is a “Gold” model RCA television set.
`
`In
`
`the second example,
`
`the user uses the on—screen display 15
`
`to identify the type (TV), brand (RCA) and model
`
`(Gold) of
`
`second electronic consumer device 14. Key code generator
`
`device 12 determines the appropriate codeset that controls
`
`television set 14.
`
`The user then presses a key on remote
`
`control device 11 associated with a function that the user
`
`wants performed by television set 14.
`
`For example,
`
`the
`
`function is to advance the channel of television set 14.
`
`When the user presses the channel advance key on remote
`
`control device 11, an indication of the pressed key is
`
`transmitted in an RF keystroke indicator signal from remote
`
`control device 11 to key code generator device 12.
`
`[0040] Key code generator device 12 then determines which
`
`key code of the identified codeset corresponds to the
`
`pressed key. Key code generator device 12 modulates the
`
`12
`
`0015
`
`0015
`
`

`

`ZIL-568
`
`PATENT
`
`key code for the channel advance function onto an RF
`
`carrier signal,
`
`thereby generating a third key code signal
`
`25. Key code generator device 12 uses the same modulation
`
`technique to generate both third key code signal 25 and
`
`first key code signal 19. Third key code signal 25 is
`
`modulated using timing information associated with the
`
`codeset that controls RCA Gold television set 14.
`
`[0041]
`
`In this second example,
`
`television set 14 has an RF
`
`receiver 26 and is capable of receiving RF key code
`
`signals.
`
`RF transmitter 20 of key code generator device 12
`
`transmits third key code signal 25 directly to television
`
`set 14. Third key code signal 25 is received onto
`
`television set 14 by RF receiver 26, and RF receiver 26
`
`recovers the key code from third key code signal 25.
`
`Television set 14 is thereby instructed to advance the
`
`channel.
`
`[0042] Although remote control device 11 in the first
`
`example stores either a proprietary codeset or a
`
`standardized codeset and uses that codeset to generate
`
`keystroke indicator signal 16,
`
`remote control device 11
`
`stores only that single codeset. This codeset is the
`
`codeset used by key code generator device 12 to receive
`
`communications from remote control device 11. Remote
`
`control device 11 can therefore be made inexpensively and
`
`may contain a relatively small amount of memory.
`
`The
`
`memory may, for example, be read only memory (ROM) on a
`
`microcontroller integrated circuit
`
`(for example, a Z8
`
`microcontroller available from Zilog,
`
`Inc. of San Jose,
`
`C14.)
`
`[0043] Even though remote control device 11 stores only a
`
`single codeset, system 10 of figure 1 nevertheless allows
`
`remote control device 11 to control the desired electronic
`
`13
`
`0016
`
`0016
`
`

`

`ZIL-568
`
`PATENT
`
`consumer device 13, which may use any one of thousands of
`
`different codesets. Key code generator device 12 may, for
`
`example,
`
`include a hard disk or other mass storage device
`
`that stores thousands of possible codesets.
`
`The user may
`
`use remote control device 11 to select any one of those
`
`codesets for communication with the particular electronic
`
`consumer device 13.
`
`In comparison to some conventional
`
`systems where codesets are downloaded into a universal
`
`remote control device from a personal computer or other
`
`device that is not normally part of an entertainment
`
`system, system 10 uses preexisting hardware of the
`
`entertainment system (such as the on—screen display
`
`functionality, data storage capability, and wireless
`
`communication ability of the set—top box)
`
`to source and
`
`identify codesets.
`
`[0044] Although the specific embodiments of figures 1 and
`
`2 are explained above in connection with the codesets being
`
`identified to the key code generator device 12 using an on—
`
`screen display,
`
`the codeset usable to communicate with an
`
`electronic consumer device may be identified to key code
`
`generator device 12 in other ways in other embodiments.
`
`In
`
`one embodiment, for example,
`
`the key code generator device
`
`includes autoscan functionality. Key code generator device
`
`12 includes an EMI detector 27 that detects electromagnetic
`
`interference (EMI) or noise on power cord 28.
`
`Power cord
`
`28 is a power cord through which key code generator device
`
`12 receives electrical power from a wall socket 29.
`
`Similarly,
`
`television set 14 receives power from another
`
`wall socket 30 via a power cord 31.
`
`VCR 13 receives power
`
`from a wall socket 32 via another power cord 33.
`
`In
`
`accordance with the autoscan functionality, key code
`
`generator device 12 identifies the codeset used to
`
`14
`
`0017
`
`0017
`
`

`

`ZIL-568
`
`PATENT
`
`communicate with a particular electronic consumer device by
`
`generating and transmitting a sequence of key code signals
`
`relayed through remote control device 11 to the electronic
`
`consumer device to be controlled (in this case VCR 13).
`
`Each of these key code signals contains a different key
`
`code corresponding to the same desired function on
`
`different device types, brands and models.
`
`[0045]
`
`In one example,
`
`the desired function is the function
`
`of powering on VCR 13.
`
`The key code generator device 12
`
`sends the power—on key codes for each of a series of
`
`codesets one-by-one to VCR 13. When the key code for one
`
`of the codesets causes VCR 13 to perform the desired
`
`function (in this case,
`
`to power on), VCR 13 introduces
`
`noise or other electromagnetic interference via cord 33
`
`into wall socket 32.
`
`The power terminal within wall socket
`
`32 is connected through wiring 34 to the power terminal
`
`in
`
`wall socket 29.
`
`The noise generated by VCR 13 is therefore
`
`communicated through wiring 34,
`
`the power terminal of wall
`
`socket 29 and power cord 28 to EMI detector 27 on key code
`
`generator device 12. When key code generator device 12
`
`detects the electromagnetic interference on power cord 28,
`
`key code generator device 12 automatically identifies the
`
`codeset used by VCR 13 as the codeset used to communicate
`
`the last key code signal for the power—on function.
`
`[0046] Multiple electronic consumer devices may have the
`
`same key data for a particular function, for example,
`
`the
`
`power—on function.
`
`A key code, however, also contains a
`
`system code (see figure 3)
`
`that corresponds to a particular
`
`type of electronic consumer device.
`
`For example,
`
`the
`
`system code used for a television set will typically be
`
`different than the system code used for a video cassette
`
`recorder. Thus, different device types that use the same
`
`15
`
`0018
`
`0018
`
`

`

`ZIL—568
`
`PATENT
`
`key data for the power—on function will not respond to a
`
`key code containing an incorrect system code.
`
`Each of the
`
`power—on key codes transmitted in this example by key code
`
`generator device 12 contains the system code for a video
`
`cassette recorder, so television set 14 does not recognize
`
`the key codes. Because key code generator device 12 is
`
`aware of the system code communicated, key code generator
`
`device 12 determines that it was VCR 13 that was powered on
`
`and not television 14.
`
`[0047]
`
`In another example,
`
`the codeset usable to
`
`communicate with VCR 13 is identified to key code generator
`
`device 12 using autoscan functionality that does not
`
`involve key code generator device 12 having a specialized
`
`EMI detection circuit.
`
`In that case,
`
`the user may be
`
`prompted by successive screens of on screen display 15 to
`
`push the power-on key on remote control device 11 multiple
`
`times.
`
`Each time the power-on key is pressed, keystroke
`
`indicator signal 16 communicates this to key code generator
`
`device 12. Key code generator device 12 in turn generates
`
`and transmits a key code signal containing a power-on key
`
`code using a different codeset. Each key code signal is
`
`relayed through remote control device 11 to the particular
`
`electronic consumer device to be controlled.
`
`One by one
`
`the user is prompted to push the power—on key, and key code
`
`generator device 12 in turn generates key codes using
`
`differ