United States Patent
`Allard et al.
`
`[19]
`
`|||||||ll|||i|||||||||l||||||||l||1|||||l|||||l|||||llllillllllllliilll||||
`US005561705A
`
`[11]
`
`Patent Number:
`
`5,561,705
`[45]
`Date of Patent:
`Oct. 1, 1996
`
`[54]
`
`[75]
`
`APPARATUS FOR AUTO DIALING
`TELEPHONE NUMBERS AND DTMF TONES
`IN A PERSONAL COMMUNICATION
`DEVICE
`
`Inventors: David J. Allard, Boyton Beach; Peter
`R. Eastwood, Delray Beach; Julie F.
`Goodwin, Boca Raton; James R.
`Lewis, Coconut Creek; David J.
`Rasmussen, Boca Raton, all of Fla.
`
`[73]
`
`Assignee:
`
`International Business Machines
`Corporation, Armonk, NY.
`
`[21]
`
`[22]
`
`[51]
`[52]
`[58]
`
`[56]
`
`App]. No.: 279,652
`
`Filed:
`
`Jul. 25, 1994
`
`Int. Cl.‘5 ....................................................... H04Q 7/32
`U.S. Cl.
`............................. 379/58; 379/354; 379/355
`Field of Search ........................ 379/58, 59, 354—356
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`, Re. 34,034
`4,697,281
`
`8/1992 O’Sullivan .
`9/1987 O’Sullivan.
`
`4,837,800
`4,964,156
`4,972,457
`4,980,910
`5,127,041
`5,257,397
`5,263,078
`5,276,729
`5,282,238
`
`6/1989
`10/1990
`11/1990
`12/1990
`6/1992
`10/1993
`11/1993
`1/1994
`1/1994
`
`.
`Freeburg et a1.
`Blair ........................................ 379/355
`O’Sullivan .
`Oba et a1.
`............................... 379/354
`O’Sullivan .
`Barzegar et a].
`.
`Takahashi et a1.
`Higuchi et a1.
`......................... 379/356
`Berland .
`
`.
`
`Primary Examiner—Dwayne D. Bost
`Attorney, Agent, or Firm—Pollock, Vande Sande & Priddy
`
`[57]
`
`ABSTRACT
`
`A radio telephone which communicates via cellular tele-
`phone networks and by direct connection to a PSTN. The
`radio telephone includes a random access memory for
`storing a character string comprising dialing digits defining
`a calling number and DTMF digits representing signalling
`tones for accessing information to called equipment. The
`character string includes a delimiting character for separat-
`ing dialed digits and DTMF digits. In a dialng sequence, the
`cellular radio will dial numbers defined by the dial digits and
`send the remaining characters as DTMF tones to connected
`telephone.
`
`8 Claims, 5 Drawing Sheets
`
`7035551212.,.,,,,,,,ABC.3,2,4 N53
`
`54
`
`o
`
`INA
`
`CALL?
`
`No
`
`CHECK FOR FIRST
`COMMA(.)
`
`YES
`
`6
`
`5
`
`GO TO 66
`
`55
`
`59
`
`COMMA
`FOUND
`
`CALL DIAL ROUTINE
`
`YES
`
`
`REPLACE.”
`mm NULL
`
`55
`
`57
`
`50
`
`CELLULAR
`
`TELEPHONE
`
`DIAL COMPLETE
`
`73
`
`65
`
`REPLACE NULL
`WITH ","
`
`
`
`
`
`READ NEXT CHAR
`
`DTMF COMMAND
`h-
`m 7274
`
`DELAY
`
`68
`
`APPL-1010 / Page 1 of11
`Apple v. Uniloc
`
`APPL-1010 / Page 1 of 11
`Apple v. Uniloc
`
`

`

`US. Patent
`
`Oct. 1, 1996
`
`Sheet 1 of 5
`
`5,561,705
`
`23
`
`FIG.
`
`IB
`
`APPL-101O / Page 2 of 11
`
`APPL-1010 / Page 2 of 11
`
`

`

`US. Patent
`
`Oct. 1, 1996
`
`Sheet 2 of 5
`
`5,561,705
`
`mummm
`
`rm
`
`mm
`
`Zmo—02E
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`
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`mph/Emzmo
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`
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`
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`
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`
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`
`APPL-1010 / Page 3 of 11
`
`APPL-1010 / Page 3 of 11
`
`
`
`
`

`

`US. Patent
`
`Oct. 1, 1996
`
`Sheet 3 of 5
`
`5,561,705
`
`film”
`
`Address Book
`
`Address Book
`10/07/1993
` FIG. 3A \
`Address
`03:49:15
`
`
`Addrus Book
`10/07/1993
`Address
`05:49:15
`
`
`
`FIG. 3C
`
`APPL-101O / Page 4 of 11
`
`APPL-1010 / Page 4 of 11
`
`

`

`US. Patent
`
`Oct. 1, 1996
`
`Sheet 4 of 5
`
`5,561,705
`
`06/17/1993
`
` Address Book
`
`Address
`
`
`
`11:23:
`
`List A
`
`18M
`386291 Side
`
`Salt Lake City, UT
`80684
`
`7035551212....ABC
`
`Bio! Home
`
`555—9322
`
`
`
`
`
`
`
`®IE§ZJ<13
`
`FIG. 30
`
`APPL-1010 / Page 5 of 11
`
`APPL-1010 / Page 5 of 11
`
`

`

`US. Patent
`
`Oct. 1, 1996
`
`Sheet 5 of 5
`
`5,561,705
`
`7035551212,,,,,,,,.,ABC,3,2,4 N53
`
`54
`
`GO TO 66
`
`YES
`
`NO
`
`CHECK FOR FIRST
`COMMA(,)
`
`55
`
`YES
`
`55
`
`59
`
`COMMA
`FOUND
`
`
`
`
`
`CALL DIAL ROUTINE
`
`5O
`
`CELLULAR
`
`DIAL COMPLETE
`
`REPLACE":
`NUL
`
`57
`
`TELEPHONE
`
`APPL-1010 / Page 6 of 11
`
`APPL-1010 / Page 6 of 11
`
`

`

`5,561,705
`
`1
`APPARATUS FOR AUTO DIALING
`TELEPHONE NUMBERS AND DTMF TONES
`IN A PERSONAL COMNIUNICATION
`DEVICE
`
`2
`
`party’s equipment cannot be sent as a single string with the
`dial digits.
`In view of these difficulties, the present invention has
`been provided.
`
`RELATED APPLICATIONS
`
`This application is related to the following patent appli—
`cations:
`
`10
`
`(1) Attorney Docket No. BC994-050 is Ser. No. 08/310,
`728, filed Sep. 22, 1994;
`(2) Attorney Docket No. BC994—096 is Ser. No. 08/279,
`640, filed Jul. 25, 1994;
`(3) Attorney Docket No. BC994-099 is Ser. No. 08/ 179,
`644, filed Jul. 25, 1994;
`
`(4) Attorney Docket No. BC994—097 is Ser. No. 08/279,
`413, filed Jul. 25, 1994; and,
`
`(5) Attorney Docket No. BC994—101 is Ser. No. 08/279,
`659, filed Jul. 25, 1994.
`1. Field of the Invention
`
`The present invention relates to personal communication
`devices which communicate over both cellular radio net-
`works and public switched networks (PSTN). More particu—
`larly,
`the invention provides for autodialing and DTMF
`signalling over the cellular radio network or PSTN network.
`2. Background of the Invention
`Cellular radio service is now widespread throughout most
`of the United States. Standards have been promulgated to
`permit universal access to the cellular telephone network by
`portable telephones and mobile telephones. The communi-
`cation protocol standard used in the cellular network is
`identified as the AMPS protocol. The service permits radio
`telephone communication between portable/mobile units,
`and the public switched telephone network (PSTN) through
`a radio interface.
`The cellular service is now digitized and permits not only
`digital telephone traffic but data services as well. Thus,
`various services which have been implemented in the PSTN
`network, such as E—MAIL and facsimile, may now be
`implemented as well over the cellular telephone network. A
`radio modem is implemented at each personal communica-
`tion device which provides for the capability of transmitting
`and receiving data on the transmitted carrier signal.
`The public switched network supports various user ser-
`vices such as accessing equipment through the use of a
`personal information number (PIN). Using DTMF signal-
`ling, a caller who places a call to a bank or to his home or
`office message recording equipment, can access the equip-
`ment by inserting his PIN number via DTMF tones from the
`telephone keypad. Dialing equipment exists for entering not
`only the number of the called party supporting such equip-
`ment, but also the PIN information as DTMF signalling
`tones following the dialing digits. As the PSTN network
`employs DTMF signals for placing a call as well as for
`transmitting a PIN number, such information may be sent as
`a single character string, with separating pauses between the
`dialing digits and PIN number.
`The same type of service is also desirable over cellular
`telephone networks which communicate with personal com—
`munication devices. However,
`the protocol used in the
`cellular communication network presents an obstacle in
`forming character strings which include dial digits as well as
`DTMF signalling information. As the AMP cellular radio
`service does not use the DTMF signalling tones for placing
`a call, the DTMF command signals for accessing the called
`
`15
`
`20
`
`25
`
`30
`
`35
`
`.40
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`45
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`50
`
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`
`60
`
`65
`
`SUMMARY OF THE INVENTION
`
`It is an object of this invention to provide compatible
`signalling in a personal communications device which sup-
`ports cellular telephone communications as well as commu-
`nications over the PSTN network.
`
`It is a more specific object of this invention to combine in
`a single string of characters a dial command and a DTMF
`signalling command for a cellular telephone system.
`It is a more specific object of this invention to provide a
`system for delimiting dialing digits and DTMF signalling
`digits in a string of characters for processing by a cellular
`telephone.
`These and other objects of the invention are provided for
`by an apparatus used in a personal communications device.
`A personal communication device supports telephone and
`data traflic via a cellular telephone network as well as
`through a direct connection to the PSTN network at the
`option of the user. When placing calls with the personal
`communication device which include DTMF signalling
`commands for accessing the called party’s equipment, a
`single character string of digits is formed. The single string
`of digits includes the dialing digits for placing the call as
`well as the DTMF signalling digits to be sent over the
`connection representing personal information or commands
`relating to the personal information.
`The single character string is delimited between those
`digits which comprise the called party’s dialed digits and the
`remaining digits representing a DTMF command with a
`delimiting character. The delimiting character maybe a
`comma placed in the string of characters by the user delim—
`iting dial digits from DTMF commands. A processor
`executes a command to place a telephone call over the
`cellular telephone by individually reading out each digit and
`marking the first coma in the string with a null character.
`The cellular telephone treats each character preceding the
`null character as a digit of the called party’s telephone
`number.
`
`Additional commas following the first null digit indicate
`a delay following which DTMF digits are transmitted. Thus,
`the cellular telephone, after detecting the null digit, will wait
`a period of time represented by the number of commas in the
`string before commencing DTMF signalling using the
`remaining digits.
`Before forwarding the string of characters to the cellular
`telephone,
`the system checks to determine whether the
`cellular telephone is already in use. If so, the entire string of
`characters is sent as a DTMF command to the cellular
`telephone network.
`
`DESCRIPTION OF THE FIGURES
`
`FIG. 1A is a plan view of a personal communication
`device employing a preferred embodiment of the present
`invention.
`
`FIG. 1B is an end view of the personal communication
`device of FIG. 1A.
`FIG. 2 is a block diagram of the device of FIG. 1
`illustrating the personal communication device of the pre-
`ferred embodiment of the invention.
`
`APPL-101O / Page 7 of 11
`
`APPL-1010 / Page 7 of 11
`
`

`

`5,561,705
`
`3
`FIG. 3A illustrates the first screen of an address book/auto
`dialer feature of the personal communication device of FIG.
`1.
`
`FIG. 3B is a second screen associated with the address
`book/auto dialer of the personal communication device of
`FIGS. 1A and 1B.
`FIG. 3C illustrates the third screen of the address book/
`auto dialer of the personal communication device of FIGS.
`1A and 1B.
`
`FIG. 3D illustrates the screen presented to the user when
`using the address book/auto dialer to place a telephone call.
`FIG. 4 is a flow chart of the routine executed by the
`processor of FIGS. 1A and 1B for autodialing a called
`number from a character string which includes DTMF
`signalling characters.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`
`Referring now to FIG. 1A, there is shown a personal
`communication device 10. The personal communication
`device includes a cellular telephone and an internal data
`processing system for implementing, via cellular radio,
`multiple data communication features, such as E-MAIL,
`facsimile transmission/reception, etc. The personal commu—
`nicator 10 includes a housing 12 which has pushbuttons 14,
`16 and 18 mounted along lateral sides thereof. Manual
`pushbuttons 14, 16 and 18 provide for on/off, up (increase)
`and down (decrease) functions.
`
`The personal communication device 10 includes a speaker
`22 and microphone 24 positioned at approximately the
`standard telephone handset positions. In use, the cellular
`telephone communicates through antenna 20 to provide
`normal two-way voice communication between the user and
`a base station connected to the PSTN network.
`
`Input/output functions to the processor within the per-
`sonal communications device 10 are effected through the
`touch-sensitive screen 28, and underlying touch screen dis~
`play 26. The touch screen display 26 displays various menus
`familiar to computer users, and various selection icons. By
`using a small pointed stylus 23, it is possible to select among
`menu selections appearing on the touch screen display 26 by
`pressing stylus 23 against the portion of the touch—sensitive
`screen 28 overlaying the display 26.
`The touch-sensitive overlay which identifies user selec-
`tions made with the stylus 23, encodes the selection and is
`read by the processor resident within personal communica~
`tion device 10.
`
`Various functions such as increased volume, decreased
`volume,
`increased brightness, decreased brightness, etc.
`may be implemented by selecting the appropriate menu
`function from touch screen display 26 and then operating
`one of switches 16 or 18.
`
`The personal communicating device of FIG. 1A also
`includes a standard RJll jack 25 as shown in FIG. 1B. The
`personal communication device can be directly coupled to
`the PSTN network through a standard telephony cable in
`those circumstances where cellular radio is not needed.
`
`The protocols used in cellular radio for placing a call and
`answering a call are set forth in the AMPS standards. These
`protocol functions are carried out in a different format,
`suitable for RF communications different from the signalling
`used in the PSTN network for the same functions. The
`personal communication device of FIGS. 1A and 1B there-
`fore includes interface circuitry peculiar to the cellular
`
`5
`
`10
`
`15
`
`20
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`25
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`4o
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`45
`
`50
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`55
`
`60
`
`65
`
`4
`
`telephone network protocols and the PSTN network proto-
`cols so that communication through both networks is pos-
`sible.
`
`A block diagram of the electronic circuitry architecture
`for the personal communication device of FIG. 1A is shown
`in FIG. 2. Referring now to FIG. 2, a CPU 32 is shown
`which controls the display of various user menus on the
`touch-screen display 26, as well as provides an interface
`between the cellular radio 50 and modem 35.
`
`The system of FIG. 2 operates from programming infor~
`mation contained in EPROM 36, EPROM 38 and RAM 34.
`RAM 34 stores the application programs, such as the one for
`the address book/auto dialer, one for placing a call over the
`cellular radio 50, etc. The system implementation emulates
`that of a PC/XT class portable computer. The CPU 32
`belongs to the type of Model VG 230, commercially avail~
`able from VADEM, Inc., San Jose, Calif. The CPU 32 and
`its companion controller include an LCD controller 40, a
`communications port and various power and bus connec-
`tions to the bus 33.
`
`The EPROM 36 stores the basic input/output system
`(BIOS), as well as a self-test program. EPROM 38 contains
`files for providing a navigator program, the DOS and certain
`application programs which produce the communication and
`data processing functions, as well as interrupt handling for
`the CPU 32. Further details relating to this architecture can
`be found in US. patent application Ser. No. 08/146,342,
`filed Nov. 1, 1993 (Attorney Docket No. BC993-O79, com—
`mon assignee).
`The operation of the touch-screen display 26 and touch
`screen overlay 28 is controlled from a touchscreen control-
`ler 40. A screen driver 48 provides the illuminating voltages
`and character drive signals to the touch screen display 26.
`The touch~sensitive screen 28 comprises an array which will
`sense a force applied to a particular part of the touch overlay
`28 and encode the same as position information. Touch
`screen controller 40, via the bus 33, can provide a command
`identifying the location touched on the touch-sensitive
`screen 28 to the CPU 32. CPU 32 can then invoke the
`selected application program or subroutine of an application
`program stored in the RAM 34 for execution.
`A tone generator 44 is shown which will produce an
`audible beep in the speaker 22 each time the screen is
`touched by the user using the stylus 23 and a command is
`successfully decoded. Thus,
`the user can audibly detect
`when his selection has been recognized.
`The integrated cellular and PSTN interface is connected
`to the antenna 22 for transmitting and receiving to the local
`cellular network. The cellular telephone 50 produces a
`cellular ring signal indicating that an incoming call is being
`received by the cellular radio 50. Further, the ACC interface
`39 provides a standard PSTN ring voltage from the RJll
`connector 25 tip and ring connections. A common ring
`generator 41 receives the ring voltage from the ACC inter-
`face 39 and cellular radio 50 and produces a single PSTN
`mode ring signal for modem 35.
`In this way, modem 35 is initialized with a PSTN ting
`signal whether the incoming call is received via cellular
`radio 50 or over the PSTN RJll jack 25. The modem 35
`responds to the PSTN ting signal by posting an interrupt to
`the CPU 32 which invokes the routine for communicating by
`modern. Incoming data from either the PSTN network or
`cellular radio 50 is received by the modem 35 as standard
`modem signalling tones and processed in the usual way.
`Further, data is output from the modem 35 to both the
`cellular radio 50 and interface 39 providing communication
`through either medium.
`
`APPL-1010 / Page 8 of 11
`
`APPL-1010 / Page 8 of 11
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`

`

`5
`
`6
`
`5,561,705
`
`The capability of providing data communication through
`either the R111 jack 25 or cellular radio 50 must take into
`account different formats of the cellular radio network and
`PSTN network. When placing a call over the cellular radio
`network 50, .the cellular radio 50 invokes the AMPS pro-
`tocol application for sending dial digits via the radio inter—
`face to a base station.
`'
`
`The standard for placing calls on the PSTN network uses
`DTMF tones corresponding to called number digits. DTMF
`tones are also used to access equipment connected to the
`called party’s telephone, such as banking information, voice
`mail messages, etc.
`Various telephdne equipment provides auto dialing fea-
`tures which will generate DTMF digits for placing a call
`over the PSTN network, followed by a series of DTMF
`digits which access equipment connected to the called
`station. In the cellular telephone environment, however,
`DTMF signalling is not used to identify the dial digits of a
`called party, hence transmitting a character string which
`includes digits of a called party’s telephone number, fol-
`lowed by DTMF signalling digits must be delimited to
`prevent the cellular telephone from transmitting the PIN
`number as part of the dialing sequence.
`The system of FIGS. 1A, 1B and 2 permits an auto dialing
`feature to be implemented for placing calls over the PSTN
`network as well as the cellular telephone network. An
`address/auto dialer is configured from an application pro-
`gram stored in RAM 34.
`Among the menu selections presented to the user is an
`icon identified as ADDRESS BOOK 29 on the face of the
`touch screen display 26. When the icon 29 is selected using
`the stylus 23, a full screen such as shown in FIG. 3A appears
`on the touch screen display 26. The display shows a series
`of file folder tabs labelled A through Z. By selecting a tab of
`FIG. 3A, using the stylus 23, a second screen, FIG. 3B, is
`presented. This would include all the names as well as a
`telephone number, not visible but stored in a memory
`location linked to the particular displayed name.
`An icon presented with FIG. 3B, labeled NEW ENTRY,
`permits the user to enter yet additional names in this
`particular page of the address book. When the new entry
`icon is selected with stylus 23, a screen shown as FIG. 3C
`is illustrated. The user can then enter a new entry in the
`address book including phone number. The phone number is
`entered as a series of digits including any particular access
`codes, area codes, seven digit phone number, followed by
`pauses and PIN number information. Thus, the user could
`program his own office telephone number, using the screen
`of FIG. 3C, as well as any access code or personal identi-
`fication number to reach a voice mail box, bank account
`information, or other personal
`information requiring an
`access code.
`
`FIG. 3D illustrates the screen presented to the user when
`placing a call using a previously entered telephone number.
`The telephone number may include a set of dialing digits and
`an access code.
`
`A typical character string representing a telephone num-
`ber and access code entry may look as follows:
`703 5551212, , ,AB C
`With the foregoing character string in a conventional
`DTMF dialing system, all digits would be produced as
`DTMF tones corresponding to each digit. Commas would be
`interpreted as a pause of a finite length. As is known to users
`of telephone accessed equipment, a delay time is necessary
`before inputting access codes to permit the called station to
`go off hook and connect to a DTMF response unit. The
`
`10
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`
`65
`
`commas appearing in the character string will provide the
`required delay determined by the user’s experience.
`When using the foregoing auto dialing feature in a cellular
`telephone environment, problems result because the cellular
`telephone does not use, per se, DTMF tone signalling. Thus,
`the entire character string such as shown above, would be
`treated as dialed digits and not as DTMF tones.
`The foregoing feature address book/auto dialer feature
`can be implemented in a cellular telephone by an application
`program which will process the character string and delimit
`the dialed digits from any following access code. In accor-
`dance with the preferred embodiment, the user inserts a
`delimiting character which may be a comma between the
`dial digits and the access code. A null character such as # is
`inserted at the end of the character string.
`An application program executing the functions of FIG. 4
`may be invoked when the user places a call, via the cellular
`network from an entry from the address book of FIG. 3D
`which includes a DTMF encoded access code.
`
`Referring now to FIG. 4, there is shown the processing of
`a character string 53. A first decision block 54 determines
`whether or not a call has already been placed. If so, each of
`the digits contained within the string 53 are processed in step
`66 as DTMF characters.
`
`the character string 53 includes both
`Assuming that
`dialing digits for establishing a telephone connection over
`the cellular network and DTMF digits, the process continues
`to step 56. The program will count, left to right, the digits of
`the character string 53 and determine whether there is a first
`comma appearing therein. If so, decision block 55 will set a
`flag in step 58, and replace the coma in step 57 with a null
`character. The null character will delimit where DTMF
`signalling digits begin and dial digits end.
`Having so delimited the character string 53, a call dial
`routine is entered in step 59 for dialing the digits preceding
`the null character using cellular telephone 50.
`Once the dialing is completed, decision block 73 deter-
`mines whether there was a flag set in step 58, indicating the
`presence of a comma. If so, step 65 replaces the null
`character with the original comma. After a delay imposed by
`69, the remaining characters are processed as DTMF char-
`acters.
`
`Step 66 reads the next character following the first
`comma, and if it is not a second null character as determined
`in 67, it is checked again in decision block 70 to determine
`whether a comma is present. If the read character is a
`comma, a delay is imposed in step 68 before returning to
`step 66 to read the next character. When a subsequent
`character is detected which is not a comma, as determined
`in decision block 70, a DTMF command is issued in step 72
`to transmit the character as a DTMF tone over the cellular
`telephone.
`The reading of characters in the string continues until a
`null character is reached in step 67 and which indicates the
`end of the string 11.
`Thus, the foregoing routine executed by the CPU 32 will
`correctly delimit the dial digits from DTMF tones while
`treating commas during DTMF signalling as a delay in the
`process for dialing. Thus, users may insert commas when
`creating a character string 53 to provide sufficient time for
`the answering telephone equipment to go off hook to connect
`to DTMF recognition equipment.
`Thus, it is clear that the personal communications device
`of FIGS. 1A, 1B and 2 is capable of providing DTMF
`signalling in the same character string even though commu-
`nications are routed by cellular telephone communications
`or standard telephone line modem communication. Those
`
`APPL-1010 / Page 9 of 11
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`APPL-1010 / Page 9 of 11
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`

`

`5,561,705
`
`8
`represented by each
`separated by a time interval
`comma which is found between characters.
`4. The radio telephone of claim 2, wherein the identifying
`means inserts each a null character in the string of characters
`in place of said first character to delimit the dialing digits
`from DTMF digits, and replaces said null character with a
`comma when said call has been placed.
`5. The radio telephone of claim 4, wherein each comma
`including said replaced comma represents a time delay
`between each DTMF tone transmitted by said radio tele—
`phone.
`6. A method of controlling a radio telephone to place a
`telephone call and transmit a series of DTMF digits con-
`tained in the same character string as dial digits comprising:
`storing in a register a series of digits including a sequence
`of DTMF digits, which include dial digits separated
`from said DTMF digits by at least one comma;
`detecting if said radio telephone is busy with an existing
`call;
`
`reading each character in said register and identifying the
`first coma in said register as a delimiter to separate
`dialing digits and DTMF digits if said radio telephone
`is not busy and as a pause in a series of DTMF digits
`if said radio telephone is busy;
`forming a dial command from said dialing digits, if any,
`and forwarding said command to a radio telephone for
`placing a call to a receiving device identified by said
`dialing digits; and,
`forming a DTMF command for each of said digits fol-
`lowing said comma, and forwarding said DTMF com-
`mands to said radio telephone along with each of said
`following digits, whereby said radio telephone places
`said call and subsequently transmits said DTMF digits
`to said called receiving device.
`7. The method according to claim 6 further comprising
`during the reading of each character following said first
`comma, delaying the transmission of said DTMF digits a
`delay period which is proportional to the number of said
`commas.
`
`8. The method according to claim 6, further comprising
`the steps of: before reading each character in said string,
`determining whether said radio telephone is engaged in a
`call; and,
`
`7
`
`skilled in the art will recognize yet other embodiments of the
`invention described more particularly by the claims which
`follow.
`What is claimed is:
`
`1. In a radio telephone system, an apparatus for transmit-
`ting a data string representing DTMF tones which may
`include a preceding series of dialing digits followed by a
`predefined delimiter comprising:
`a radio telephone having a computer interface connected
`to receive commands from a data bus; a random access
`memory for storing a character string;
`a data processor connected by said bus and to said random
`access memory and to said radio telephone, said data
`processor being programmed to create logic means
`comprising:
`phone busy means for detecting whether said radio tele-
`phone is engaged in a telephone call;
`means, responsive to said phone busy means indicating an
`active call, for reading said character string and for
`sending commands over said data bus to cause said
`radio telephone to send DTMF tones corresponding to
`the entire character except for the delimiter character
`which is interpreted as a pause;
`means, responsive to said phone busy means indicating no
`active call, for reading each character of said stored
`character string and for identifying each delimiter char-
`acter in said character suing, the first of said characters
`delimiting the end of dialing digits and the beginning of
`DTMF digits;
`means for sending a command over said bus to said radio
`telephone to place a call to a party identified by said
`dialing digits;, if any, and,
`means for sending a subsequent command to said radio
`telephone to transmit each character following the first
`said delimiter character as DTMF tones except delim-
`iter characters.
`
`2. The radio telephone apparatus of claim 1, wherein the
`delimiter character is a comma and each comma following
`said dialing digits represents a time delay interval between
`each command to transmit a character as a DTMF tone.
`3. The radio telephone apparatus of claim 1, further
`comprising the programming step of:
`prior to reading each character, determining if said radio
`telephone is engaged in a telephone call; and,
`if said radio telephone is determined to be in a telephone
`call, sending a series of commands to said radio tele—
`phone to transmit all of said characters as DTMF digits
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`transmitting all of said characters as DTMF digits if said
`radio telephone is engaged in a call, and introducing a
`delay between transmission of digits for each comma
`detected between digits.
`*
`*
`
`*
`
`*
`
`*
`
`APPL-101O / Page 10 of 11
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`APPL-1010 / Page 10 of 11
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`

`

`UNITED STATES PATENT AND TRADEMARK OFFICE
`CERTIFICATE OF CORRECTION
`
`PATENTNO.
`
`DATED
`
`:
`
`=
`
`5,561,705
`
`October 1, 1996
`
`INVENTOR(S)I
`
`Allard et a1.
`
`It is certified that error appears in the above-indentified patent and that said Letters Patent is hereby
`corrected as shown below:
`Column 7:
`
`In claim 1,
`Column 8:
`In claim 4, line 2, change "means inserts each" to
`
`line 31, after "except", insert -—said--.
`
`--means each inserts-—.
`
`
`
`Signed and Sealed this
`
`Thirty-first Day of December, 1996
`
`(Lea/Ml
`
`BRUCE LEHMAN
`
`Arresting Ofi‘icer
`
`Commissioner of Patent: and Trademarks
`
`APPL-101O / Page 11 of 11
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`APPL-1010 / Page 11 of 11
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`