`Nels on et al.
`
`I IIIII IIIIIIII Ill lllll lllll lllll lllll lllll lllll lllll lllll 111111111111111111
`US006341143Bl
`US 6,341,143 Bl
`Jan.22,2002
`
`(10) Patent No.:
`(45) Date of Patent:
`
`12/1993
`3/1994
`4/1994
`4/1994
`8/1994
`
`Herh et al.
`White
`Halpern
`Deaton et al.
`Folger et al.
`
`. ... ... ... 340/825.14
`
`5,268,928 A
`5,293,376 A
`5,301,122 A
`5,305,196 A
`5,337,044 A *
`(List continued on next page.)
`OTHER PUBLICATIONS
`AT&T Microelectronics, "High Speed Data Pump Chip
`Sets," published in Dec. 1991.
`Zilog Intelligent Peripheral Controllers, "Z84C01 Z80®
`CPU with Clock Generator/Controller," 43-73, published in
`1991.
`Zilog Intelligent Peripheral Controllers, "Z84C90 CMOS
`Z80® KIO Serial/Parallel/Counter/Timer," 205-224, pub(cid:173)
`lished in 1995.
`(List continued on next page.)
`Primary Examiner-Madeleine Nguyen
`(74) Attorney, Agent, or Firm----Schwegman, Lundberg,
`Woessner & Kluth, P.A.
`ABSTRACT
`
`(57)
`
`Updated operating code and parameters can be repro(cid:173)
`grammed into a modem system with no disassembly of the
`modem hardware. The modem system includes a memory
`chip in which operating code and parameters are stored. Two
`control programs control the reprogramming of updated
`operating code. One of the control programs is designed for
`manufacturing and testing purposes. The other control pro(cid:173)
`gram allows remote reprogramming of updated operating
`code or parameters from a remote location such as a cus(cid:173)
`tomer site. A user can thus remotely upgrade system firm(cid:173)
`ware with updates, bug fixes, enhancements or other new
`releases of system operating code by downloading the
`update over a phone line to a host PC and reprogramming
`the memory chip of the modem over the serial port from the
`host PC. The user can also remotely upgrade the modem
`system firmware by directly programming the memory chip
`of the modem without the assistance of the host PC. The
`modem system is portable, obtaining power from a standard
`9 volt battery. Therefore, various power saving features are
`also incorporated into the modem system
`
`8 Claims, 28 Drawing Sheets
`
`(54) MODEM WITH FIRMWARE UPGRADE
`FEATURE
`
`(75)
`
`Inventors: Craig A. Nelson, St. Paul;
`Harinarayana Arimilli, Coon Rapids;
`Richard David Johnson, Maplewood,
`all of MN (US)
`
`(73) Assignee: Multi-Tech Systems, Inc., Mounds
`View, MN (US)
`
`( *) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by O days.
`
`(21) Appl. No.: 08/368,291
`Jan. 3, 1995
`(22) Filed:
`
`Related U.S. Application Data
`
`( 63) Continuation-in-part of application No. 08/087,164, filed on
`Jul. 2, 1993.
`
`(51)
`
`Int. Cl.7 ........................... H04B 1/38; H04M 11/00
`
`(52) U.S. Cl. ..................................... 375/222; 379/93.05
`
`(58) Field of Search ................................. 375/222, 219;
`395/200, 200.01, 200.02, 200.09, 200.18,
`200.64, 200.51, 750.05; 379/93.01, 93.05,
`100.01
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`1/1980 Hong et al.
`RE30,187 E
`5/1980 Mascia
`4,203,006 A
`5/1986 Redding
`4,592,069 A
`4,725,977 A * 2/1988 Izumi et al.
`................ 364/900
`4,782,462 A * 11/1988 Kaplinsky et al. .......... 364/900
`4,830,757 A * 5/1989 Lynch et al. ................ 210/742
`4,893,271 A
`1/1990 Davis et al.
`5,001,729 A * 3/1991 Tjahjadi et al. ............. 375/106
`5,132,716 A * 7/1992 Samuels et al.
`............ 354/322
`5,155,847 A
`10/1992 Kirouac et al.
`5,175,845 A
`12/1992 Little
`5,239,652 A
`8/1993 Seibert et al.
`
`TO COMPUTER
`
`Page 1 of 43
`
`GOOGLE EXHIBIT 1019
`
`
`
`US 6,341,143 B1
`Page 2
`
`U.S. PATENT DOCUMENTS
`
`................. 395/575
`5,367,670 A * 11/1994 Ward et al.
`
`.....
`395/150
`5,390,350 A *
`2/1995 Chung et al.
`..... 379/98
`5,408,522 A *
`4/1995 Ikehata et al.
`
`.....
`395/750
`5,428,790 A *
`6/1995 Harper et al.
`
`.. 370/321
`..
`5,434,849 A *
`7/1995 Vicard et al.
`................... 371/67
`5,450,425 A *
`9/1995 Gunn et al.
`OTHER PUBLICATIONS
`
`AT&T Microelectronics, WE® DSP16C Digital Signal Pro-
`cessor/CODEC Preliminary Data Sheet, 32 pages, published
`in May, 1991.
`AT&T Microelectronics, “T7540 Digital Telephone CODEC
`Data Sheet and Addendum,” 1—4, published in Jul., 1991.
`
`AT&T Microelectronics, T7540 Digital Telephone CODEC
`Preliminary Data Sheet, 1—64, published in Jan., 1991.
`“Dynamic Setting of Modern Parameters,” IBM Technical
`Disclosure Bulletin, V0. 26, No. 1, Jun. 1983, pp. 261—262.
`“Technique for Power Management in Signal Processors,”
`IBM Technical Disclosure Bulletin, vol. 35, No. 5, Oct.,
`1992, pp. 425—427.
`“Resume Operation for Internal Modems,” IBM Technical
`Disclosure Bulletin, vol. 5, No. 48, Sep. 1992, pp. 398—399.
`
`K. Tolly, “The New Branch—Office Routers”, Data Commu-
`nications, pp. 58—70, Aug. 1994.
`
`* cited by examiner
`
`Page 2 of 43
`
`Page 2 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 1 0f 28
`
`US 6,341,143 B1
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`
`Page 3 of 43
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`Page 3 of 43
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`US. Patent
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`Jan. 22, 2002
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`Page 4 Of 43
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`US. Patent
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`Jan. 22, 2002
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`Page 11 of 43
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`US 6,341,143 B1
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`US. Patent
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`Jan. 22, 2002
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`Sheet 16 0f 28
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`
`
`
`NO
`
`READ AND
`PROCESS FILE
`
`
`
`10
`
`8
`
`
`
`
`0K
`NO
`TO PROGRAM THIS
`
`FILE
`?
`
`
`PROGRAM FILE
`INTO PRODUCT
`
`SHUT DOWN TIMERS
`
`AND RESTORE SCREEN
`
`INFORM USER FLASH
`
`CONTROL PROGRAM IS
`COMPLETE
`
`WAS FILE
`
`
`
`NAME ON COMMAND
`
`LINE
`
`?
`FIG. 8A
`
`N0
`
`807
`
`PROCESS MENU
`
`1 PORT SETUP
`
`2 READ FILE
`
`mm
`
`Page 18 of 43
`
`Page 18 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 17 0f 28
`
`US 6,341,143 B1
`
`UPDATE ONSCREEN
`HELP DISPLAY
`
`READ AND
`PROCESS FILE
`
`r810
`
`ZAP MEMORY
`BUFFER
`
`OPEN FILE FOR
`READ ACCESS
`
`READ FIRST
`RECORD
`
`
`
`
`REPORT
`
`UNKNOWN
`RECORD
`
`TYPE
`
`
`
`
`RECORD
`TYPE 01
`?
`
`
`
`PARSE
`RECORD
`
`
`
`RECORD
`N0
`RECORD
`TYPE 00
`TYPE 02
`
`
`
`?
`?
`PROCESS
`
`
`
`
`RECORD AS
`
`PROCESS RECORD
`PROCESS
`EOF
`
`
`
`RECORD AS
`AS DATA TO
`
`
`
`64K PAGE
`LOAD To MEMORY
`
`
`
`
`WERE
`NUMBER
`BUFFER AT
`
`
`
`ADDRESS
`CURRENT MEMORY
`
`
`0000. 0001, OR 0002
`POINTER
`
`
`
`PROGRAMMED
`?
`
`
`
`LAST
`
`HEX RECORD
`
`
`
`FORCE TO
`9
`OCSH, 00
`
`AND 01
`
`
`RESPECTIVELY
`
`
`
`
`
`
`NO
`
`READ NEXT
`HEX RECORD m
`
`FIG. BB
`
`Page 19 of 43
`
`Page 19 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 18 0f 28
`
`US 6,341,143 B1
`
`r820
`
`PROGRAM
`FILE INTO
`PRODUCT
`
`ROGRAM SEQUENC.
`
`INITIAUZE SERIAL
`PORT 19200. 3.
`NONE,
`1
`
`.
`SEND ARTS
`
`.
`
`m
`
`ZP0
`
`ES
`
`SEND '0'
`
`GET RESPONSE
`
`
`
`
`
`SET BAUD RATE
`BY RESPONSE
`J=19200
`
`K=19200 OR 38400
`
`M=9600,19200,38400
`
`
`57600.1 15200
`
`WAIT FOR OK
`
`INITIALIZE NEW
`BAUD RATE
`
`SEND 'ATI1'
`
`READ BOOT
`
`VERSION ,
`
`REPORT VERSION #
`
` SET MAX PACKET
`SIZE BY VERSION #
`1.07 AND LESS=128
`DSP=256
`ALL ELSE=MAX_SIZE
`=4096
`
`
`
`
`
`
`
`Page 20 of 43
`
`INITIAUZE POINTERS TO
`TOP OF RAM BUFFER
`
`IF PROTECT IS ON,
`DISABLE PROGRAM
`OF BOOT AREAS
`
`SEARCH BACKWARDS LOOKING
`FOR NON—BLANK AREA
`
`880
`
`882
`
`884
`
`886
`
`INCREMENT
`KEEP LOOKING BACKWARD,
`PACKET LENGTH UNTIL FIND BLANK
`PAGE 0R MAX PACKET LENGTH
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`a “0
`
`REPEAT 5 TIMES
`THEN ERROR AND
`
`EXIT To DOS
`
`SEND
`'ATFLEND'
`
`s
`
`.311}.
`
`FIG. 8C
`
`
`
` o
`
`DONE
`PROGRQMM'N
`
`Page 20 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 19 0f 28
`
`US 6,341,143 B1
`
`POWER UP OR
`AT * FS
`
`INITIALIZE PORT FOR
`
`19200 BAUD, COPY CODE
`TO RAM, JUMP TO RAM
`
`INITIALIZE COUNTER
`FOR 30ms
`
`GET A CHARACTER
`
`
`
`
`
`
`NO
`
`DECREMENT
`COUNTER
`
`No@
`
`ES
`EX” To
`MA'N CODE
`
`SEND 'U'
`INITIALIZE
`
`FOR 300ms
`
`GET A CHARACTER
`
`’D’
`
`N
`
`0
`DECREMENT
`COUNTER
`
`
`
`.RECEIVED
`
`?
` J=19200
`
`K=58400
`L=57600
`
`ACCEPT
`COMMANDS
`
`NO
`
`ES
`
`Page 21 of 43
`
`SEND M
`
`GET A
`CHARACTER
`
`'
`ES @NO
`M=1 15200
`
`ES
`CONFIGURE
`ACCORDING TO
`LEITER RECEIVED
`l=9600
`
`Page 21 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 20 0f 28
`
`US 6,341,143 B1
`
`GET DATA BYTE
`
`CHECKSUM=CHECKSUM 9 DATA
`
`DECREMENT COUNTER
`
`
`
`
`
`@N0
`
`YES
`
`GET CHECKSUM DATA BYTE FROM HOST PC
`
`CHECKSUM
`
`
`
`
`
`=CHECKSUM DATA
`?
`
`
`
`
`
`
`
`PROGRAM BYTES AT ADDRESS
`
`SEND ’OK'
`
`SEND 'ERROR’
`
`Page 22 of 43
`
`Page 22 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 21 0f 28
`
`US 6,341,143 B1
`
`
`
`ATFLEND RECEIVED
`
`
`
`DISABLE
`
`SERIAL PORT
`
`JUMP TO
`
`MAIN CODE
`
`
`
`
`
`COMMAND END
`
`FIG. 9C
`
`
`ATlx RECEIVED
`
`
`x=O SEND PRODUCT ID CODE
`
`x=1 SEND BOOT VERSION NUMBER
`
`
`
`
`
`
`
`
`x=2 SEND 'MT1432xx'
`x=3 SEND '000 000 000 GOO 000 000 000 000 000'
`x=/=O,1,2,3 DEFAULT TO 10
`
`
`
`FIG. 9D
`
`Page 23 of 43
`
`Page 23 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 22 0f 28
`
`US 6,341,143 B1
`
`ESTABLISH COMMUNICATIONS BETWEEN
`
`
`
`THE BULLETIN BOARD AND THE MODEM
`
`
`
`
`
`
`
`
`
`
`
`
`TO BE PROGRAMMED WITH UPGRADED CODE
`
`
`ENTER COMMAND MODE BY TRANSMITTING AN
`
`ESCAPE SEQUENCE TO THE MODEM
`
`ENTER PROGRAMMING MODE BY TRANSMITTING
`"AT * FSI” TO THE MODEM
`
`EXECUTE THE FLASH CONTROL PROGRAM AT THE
`
`BULLETIN BOARD SIDE AND DOWNLOAD
`
`2
`
`PACKETIZED UPDATED OPERATING CODE TO
`
`THE MODEM
`
`FIG. 10
`
`Page 24 of 43
`
`Page 24 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 23 0f 28
`
`US 6,341,143 B1
`
`START
`
`INITIAUZE INTERNAL
`VARIABLES AND
`
`ENVIRONMENT
`
`”“1100
`
`1108
`
`FIND AND DISPLAY
`
`FILES, ASK FOR
`FILE SELECTION
`
`READ AND
`
`PROCESS FILE
`
`@YES
`
`
`
`
`OK
`
`TO PROGRAM THIS
`FILE
`9
`
`PARSE COMMAND
`LINE PARAMEIERS
`
`SAVE AND CLEAR
`SCREEN
`
`1102
`
`START HELP SYSTEM
`
`READ SETUP FILE
`
`INITIALIZE
`
`SERIAL PORT
`
`ALLOCATE MEMORY
`
`
`
`
`1104
`
`PROGRAM FILE
`INTO PRODUCT
`
`1106
`
`SHUT DOWN TIMERS
`AND RESTORE SCREEN
`
`INFORM USER FLASH
`
`CONTROL PROGRAM IS
`
`COMPLETE
`
`WAS FILE
`NAME ON COMMAND
`
`
`
`
`LINE
`9
`
`N0
`
`1107
`
`
`
`PROCESS MENU
`
`
`
`
`
`1 PORT SETUP
`2 READ FILE
`3 PROGRAM
`4 EXIT
`
`
`FIG. 11A
`
`Page 25 of 43
`
`Page 25 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 24 0f 28
`
`US 6,341,143 B1
`
`UPDATE ONSCREEN
`HELP DISPLAY
`
`READ AND
`PROCESS FILE
`
`r1110
`
`ZAP MEMORY
`BUFFER
`
`OPEN FlE FOR
`READ ACCESS
`
`READ HRST
`RECORD
`
`PARSE
`
`
`
` REPORT
`
`UNKNOWN
`RECORD
`TYPE
`
`
`
`
`
`
`
`
`RECORD
` RECORD
`?
`TYPE 01
`
`
` PROCESS
`RECORD AS
`
`EOF
`
`
`PROCESS
`PROCESS RECORD
`
`RECORD AS
`AS DAJA TO
`
`LOAD TO MEMORY
`64K PAGE
`
`
`
`
`WERE
`NUMBER
`BUFFER AT
`
`
`
`ADDRESS
`CURRENT MEMORY
`
`
`
`
`POINTER 0000, 0001, OR 0002
`
`
`PROGRAMMED
`
`?
`
`LAST
`
`
`HEX RECORD
`9 FORCE TO
`
`
`0C3H,00
`AND 01
`
`
`RESPECRVELY
`
`
`RECORD
`TYPE 00
`?
`
`0
`
`RECORD
`TYPE 02
`?
`
`
`
`
`
`NO
`
`READ NEXT
`HEX RECORD
`
`END
`
`
`
`
`
`FIG. 113
`
`Page 26 of 43
`
`Page 26 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 25 0f 28
`
`US 6,341,143 B1
`
`[/1120
`
`1180
`
`PROGRAM
`FILE INTO
`PRODUCT
`
`ROGRAM SEQUENC.
`
`INITIALIZE SERIAL
`PORT TO MATCH
`MODEMS
`
`INITIAUZE POINTERS T0
`TOP OF RAM BUFFER
`
`IF PROTECT IS ON,
`DISABLE PROGRAM
`0F BOOT AREAS
`
`SEARCH BACKWARDS LOOKING
`
`1182
`
`1184
`
`1186
`
`INCREMENT
`KEEP LOOKING BACKWARD,
`PACKET LENGTH UNTIL FIND BLANK
`PAGE 0R MAX PACKET LENGTH
`
`FOR NON-BLANK AREA
`
`
`
`
`
`
`
`
`
`
`
`
`DONE
`No
`PROGRAMMIN
`I?
`-
`
`
`
`
`
`
`
`
`
`
`
`
`
`®N 0
`
`REPEAT 5 TIMES
`THEN ERROR AND
`EXIT T0 DOS
`
`s
`
`'ATIELIEJND’
`
`-
`END
`FIG. 11C
`
`
`
`SET BAUD RATE
`BY RESPONSE
`J=NO CHANGE
`K=19200 OR 38400
`M=9600, 19200, 38400
`57600, 115200
`
`WAIT FOR 0K
`
`INITIALIZE NEW
`BAUD RATE
`IF NECESSARY
`
`SEND 'ATII '
`
`READ BOOT
`
`VERSION ,-
`
`REPORT VERSION ff
`
`SET MAX PACKET
`SIZE BY VERSION #
`1.07 AND LESS=128
`DSP=256
`ALL ELSE=MAX__SIZE
`
`=4096
`
`Page 27 of 43
`
`Page 27 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 26 0f 28
`
`US 6,341,143 B1
`
`RECEIVE REMOTE UPGRADE
`COMMAND (AT* FSI)
`
`COPY CODE
`
`T0 RAM, JUMP TO RAM
`
`WAIT FOR REMOTE PC T0 EXIT
`DATA MODE AND PROCESS
`UPDATED OPERATING CODE
`
`
`
`
`I
`RECEIVED
`
`No@ .2) 3 @NO
`
`
`SEND 'U'
`INITIALIZE
`
`FOR 300ms
`
`GET A CHARACTER
`
`IDI
`
`NO
`
`DECREMENT
`COUNTER
`
`SEND M
`
`GET A
`CHARACTER
`
`s
`
`
`
`CONHGURE
`ACCORDING TO
`
`
`LEITER RECEIVED
`
`
`|=9600
`J=NO CHANGE
`K=384OO
`L=57600
`M=1 15200
`
`
`
`
`
`
`
`
`ACCEPT
`COMMANDS
`
`GET A CHARACTER
`
`
`
`
`NO
`
`DECREMENT
`COUNTER
`
`ES
`
`EXIT TO
`MA'N CODE
`
`N0
`
`Page 28 of 43
`
`Page 28 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 27 0f 28
`
`US 6,341,143 B1
`
`GET DATA BYTE, STORE
`
`CHECKSUM=CHECKSUM 6 DATA
`
`
`
`@NO
`
`DECREMENT COUNTER
`
`YES
`
`GET CHECKSUM DATA BYTE FROM HOST PC
`
`CHECKSUM
`
`
`
`
`
`
`=CHECKSUM DATA
`9
`
`
`
`
`
`SEND 'ERROR'
`
`COMMAND
`
`END
`
`FIG. 123
`
`Page 29 of 43
`
`Page 29 of 43
`
`
`
`US. Patent
`
`Jan. 22, 2002
`
`Sheet 28 0f 28
`
`US 6,341,143 B1
`
`
`
`ATFLEND RECEIVED
`
`
`
`PROGRAM DATA BYTES
`
`FROM RAM INTO
`
`
`
`
`
`
`
`
`
`
`
`ALL
`
`PACKETS
`
`
`
`RECEIVED
`
`
`
`0K?
`
`FLASH PROM
`
`HARD BOOT
`
`JUMP TO
`
`MAIN CODE
`
`
`
`COMMAND END
`
`
`
`HG.1ZC
`
`ATlx RECEIVED
`
`
`
`x=0 SEND PRODUCT ID CODE
`
`
`
`x=1 SEND BOOT VERSION NUMBER
`x=2 SEND 'MT‘I432xx'
`x=3 SEND '000 000 000 000 000 000 000 000 000'
`x¢0,1,2,3 DEFAULT TO 10
`
`
`
`
`
`
`
`
`
`COMMAND END
`
`HG.12D
`
`Page 30 of 43
`
`Page 30 of 43
`
`
`
`US 6,341,143 B1
`
`1
`MODEM WITH FIRMWARE UPGRADE
`FEATURE
`
`This application is a continuation-in-part of US. patent
`application Ser. No. 08/087,164, entitled “Modem with
`Firmware Upgrade Feature”, filed Jul. 2, 1993.
`
`5
`
`FIELD OF THE INVENTION
`
`The present invention relates to communications systems
`and in particular to a modem in which the firmware which
`controls the operation of the modem can be changed or
`upgraded remotely.
`
`BACKGROUND
`
`Presently, there are several mechanisms through which
`software upgrades, bug fixes and the like are distributed to
`users. In systems employing firmware storage of operating
`programs, such as Electrically Programmable Read Only
`Memory (EPROM) and the like, bug fixes or enhancements
`to system firmware require programming a new EPROM
`with the updated code and shipping the new EPROM to the
`customer. A technician then travels to the site, disassembles
`the hardware, and replaces the old EPROM with the new
`one.
`
`Unfortunately, these methods are very inconvenient. First,
`a considerable time delay is encountered while waiting for
`the manufacturer to program and ship the replacement parts.
`Second, the hardware may not be operable if the user is
`waiting for a bug fix. Especially true in cases of bug fixes
`where the hardware might not be operable without
`the
`updated operating code. Also, the replacement of the old
`with the new EPROM requires a technician to travel to the
`site and use special tools to disassemble the hardware and
`replace the outdated on faulty part or parts. This results in an
`increased expense for repairs or upgrades because technician
`time and special tools are required. Current update methods
`are thus time consuming, expensive and inefficient.
`There is a need in the art, therefore, for a modem which
`allows remote changes and/or upgrades to be made to the
`firmware stored operating code, without requiring disassem-
`bly and replacement of parts, technician time, or special
`tools, thus resulting in the more efficient and cost effective
`means of updating firmware.
`
`SUMMARY
`
`To overcome the shortcomings in the art described above,
`and to provide other advantages which will become apparent
`upon reading and understanding the present specification,
`the present system is a modem system which includes
`hardware and software components. The system allows the
`user to connect to remote locations equipped with a similar
`system or with modems or facsimile machines over a single
`analog telephone line. The incorporation of various power
`saving features allow practical implementation of a small,
`lightweight and easily transportable modem system powered
`from a standard 9 volt battery. The present modem system
`also incorporates storage of operating code and parameters
`in an in-circuit reprogrammble memory chip. Multiple
`embodiments of the present invention are discussed which
`allow for remote programming of the modem system. In one
`embodiment a user can thus remotely upgrade system firm-
`ware with updates, bug fixes, enhancements or other new
`releases of system operating code by downloading the
`update over a phone line to a host PC and reprogramming
`the memory chip of the modem over the serial port from the
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`the user can remotely
`host PC. In another embodiment,
`upgrade the modem system firmware by directly program-
`ming the memory chip of the modem without the assistance
`of the host PC.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`In the drawings, where like numerals refer to like com-
`ponents throughout the several views:
`FIG. 1 shows the telecommunications environment within
`
`which the present system may operate,
`FIG. 2 is a block diagram of the hardware components of
`the present system;
`FIG. 3 is a key for viewing the detailed electrical sche-
`matic diagrams of FIGS. 4A—7C to facilitate understanding
`of the interconnections between the drawings;
`FIGS. 4A—4E, 5A—5C and 6A—6C are detailed electrical
`schematic diagrams of the circuitry of the hardware com-
`ponents of the present system;
`FIG. 7 shows a flow diagram of the process for down-
`loading the HEX files containing the updated operating code
`from a bulletin board to the host PC in a first embodiment
`
`of the present invention;
`FIGS. 8A—8C show a flow diagram of the upgrade control
`program from the perspective of the host PC in a first
`embodiment of the present invention;
`FIGS. 9A—9D show a flow diagram of the upgrade control
`program from the perspective of the modem in a first
`embodiment of the present invention;
`FIG. 10 shows a flow diagram of the process for directly
`downloading files containing updated operating code from a
`remote PC to the modem in a second embodiment of the
`
`present invention;
`FIGS. 11A—11C show a flow diagram of the upgrade
`control program from the perspective of the remote PC in a
`second embodiment of the present invention; and
`FIGS. 12A—12D show a flow diagram of the upgrade
`control program from the perspective of the modem in a
`second embodiment of the present invention
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`In the following detailed description of the preferred
`embodiment, reference is made to the accompanying draw-
`ings which form a part hereof, and in which is shown by way
`of illustration specific embodiments in which the inventions
`may be practiced. These embodiments are described in
`sufficient detail to enable those skilled in the art to practice
`the invention, and it is to be understood that other embodi-
`ments may be utilized and that structural changes may be
`made without departing from the spirit and scope of the
`present inventions. The following detailed description is,
`therefore, not to be taken in a limiting sense, and the scope
`of the present inventions is defined by the appended claims.
`FIG. 1 shows a typical arrangement for the use of the
`present modem system. Hardware components 20 contain
`the present modem system and are connected to laptop
`computer 10. Hardware components 20 communicate over a
`standard telephone line 30 to one of a variety of remote sites.
`For example, one of the remote sites may be equipped with
`the present modem system including hardware components
`20a and laptop computer 10a. The present modem system
`can also connect over phone lines 30 to fax machine 60, to
`a personal computer and associated modem 40, or to a
`network of personal computers 90. Those skilled in the art
`
`Page 31 of 43
`
`Page 31 of 43
`
`
`
`US 6,341,143 B1
`
`3
`will readily recognize the wide variety of communication
`interconnections possible with the present system by reading
`and understanding the following detailed description.
`
`Hardware Components
`
`FIG. 2 is a block diagram of the hardware components of
`the present system corresponding to reference number 20 of
`FIG. 1. These components form the link between the user,
`the laptop or personal computer (PC) and the telephone line
`interface.
`
`The preferred embodiment of the present system prefer-
`ably includes a data pump circuit 211, which includes a
`digital
`telephone coder-decoder (CODEC) and a digital
`signal processor (DSP) for communicating over the tele-
`phone line interface 209. The data pump DSP of circuit 211
`performs functions such as modulation, demodulation and
`echo cancellation to communicate over the telephone line
`interface 209 using a plurality of telecommunications stan-
`dards including FAX and modem protocols. The main
`controller circuit 213 directly controls the DSP data pump
`circuit 211.
`
`As described more fully below, the main controller circuit
`213 includes, in the preferred embodiment, a microprocessor
`which controls the functions and operation of all of the
`hardware components shown in FIG. 2. The main controller
`is connected to RAM circuit 216 and a programmable and
`electrically erasable read only memory or Flash PROM
`circuit 217. The Flash PROM circuit 217 includes non-
`
`volatile memory in which the executable control programs
`for the main controller circuits 213 are stored
`The R8232 serial interface 215 communicates to the serial
`
`10
`
`15
`
`20
`
`25
`
`30
`
`port of the personal computer which is running the software
`components in the first embodiment of the present system.
`The R8232 serial interface circuit 215 is connected to a
`
`35
`
`serial input/output circuit 214 with main controller circuit
`213.
`
`invention, data is
`In one embodiment of the present
`received from the telephone line over telephone line inter-
`face circuit 209 and forwarded by the data pump circuit 211
`and the main controller circuit 213 over the serial
`line
`
`interface circuit 215 to the personal computer. If the data is
`upgrade program data, then it is processed and transmitted
`back to serial line interface circuit 215 to be loaded into
`
`RAM circuit 216, and ultimately, into Flash PROM circuit
`217.
`
`In a second embodiment of the present invention, upgrade
`program data is received from the telephone line over
`telephone line interface circuit 209 and stored in RAM 216
`via data pump circuit 211 and main controller circuit 213.
`The upgrade program data stored in RAM circuit 216 is later
`programmed into Flash PROM circuit 217.
`
`Detailed Electrical Schematic Diagrams
`
`The detailed electrical schematic diagrams comprise
`FIGS. 4A—E, 5A—C, 6A—C and 7A—C. FIG. 3 shows a key
`for how the schematic diagrams may be conveniently
`arranged to view the passing of signals on the electrical lines
`between the diagrams. The electrical connections between
`the electrical schematic diagrams are through the designa-
`tors listed next to each wire. For example, on the right side
`of FIG. 4A, address lines A0—A19 are attached to an address
`bus for which the individual electrical lines may appear on
`other pages as A0—A19 or may collectively be connected to
`other schematic diagrams through the designator “A” in the
`circle connected to the collective bus. In a like fashion, other
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4
`electrical lines designated with symbols such as RNGL on
`the lower left-hand side of FIG. 4A may connect to other
`schematic diagrams using the same signal designator
`RNGL.
`
`Beginning with the electrical schematic diagram of FIGS.
`4D and 4E, the DAA circuitry (telephone line interface) is
`shown. The telephone line connection in the preferred
`embodiment is through connector J201 which is a standard
`six-pin modular RJ-11 jack. In the schematic diagram of
`FIG. 4E, only the tip and ring connections of the first
`telephone circuit of the RJ-11 modular connector are used.
`Ferrite beads FB201 and FB202 are placed on the tip and
`ring wires of the telephone line connections to reduce high
`frequency or RF noise that may radiate from telephone line.
`The incoming telephone line is also overvoltage protected
`through SIDACTOR R205. The incoming telephone line is
`fill wave rectified by the full wave bridge comprised of
`diodes CR230, CR226, CR227 and CR228 of FIG. 4D.
`Also connected across the incoming telephone line is a
`ring detect circuit. Optical isolator U220 (part model num-
`ber CNY17) senses the ring voltage threshold when it
`exceeds the breakdown voltages on zener diodes CR201 and
`CR202.
`
`The DAA circuitry is physically isolated from the rest of
`the system by transformer T1, optocoupler U220 and two
`solid state relays X215 and X202 which are optically
`coupled. Connector J203 is a four pin header used for
`automatic testing during manufacturing and for diagnostics.
`Relay X215 shown in FIG. 4D is used to accomplish pulse
`dialing by opening and shorting the tip and ring wires.
`Transistor Q203 along with the associated discrete resistors
`comprise a holding circuit to provide a current path or
`current loop on the telephone line to grab the line. The DAA
`circuitry shown in FIGS. 4D and 4E can be customized to
`interface to the varying telephone standards used in the
`United States and in many different European countries.
`Connector J202 shown in FIG. 4D connects the telephone
`line interface circuitry described above to connector J102
`shown in FIG. 6A and thusly to the rest of the circuit.
`Incoming RXA signals are buffered by the two operational
`amplifers U104 as shown in FIG. 6B. The first stage of
`buffering is used to drive the transmit carrier signal to the
`telephone line. The second stage of the input buffering is
`configured for a moderate amount of gain before driving the
`signal into CODEC U101. This stage is also used to reduce
`the amount of transmit signal
`that is fed back into the
`receiver. The signal from amplifiers U104 is also fed to
`speaker driver U105, which drives speaker X10.
`Data and address buses A and B shown in FIGS. 4A and
`
`4B connect the Z80180 microprocessor in microcontroller
`U5 with the Z80 KIO circuit U4 and a gate array circuit U3,
`and to other portions of the electrical schematic diagrams.
`Gate array U3, also shown in FIGS. 4A and 4B, includes the
`“glue logic” used to support various functions in the hard-
`ware components of the present invention. Gate array U3
`includes miscellaneous latch and buffer circuits for the
`
`present system which normally would be found in discrete
`SSI or MSI integrated circuits. By combining a wide variety
`of miscellaneous support circuits into a single gate array, a
`much reduced design complexity and manufacturing cost is
`achieved.
`
`CODEC chip U101 shown in FIG. 6B, interface chip U1
`shown in FIG. 5A and digital signal processor (DSP) chip
`U2 shown in FIG. 5A comprise a data pump chip set
`manufactured and sold by AT&T Microelectronics. A
`detailed description of the operation of these three chips in
`
`Page 32 of 43
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`Page 32 of 43
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`
`
`US 6,341,143 B1
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`5
`direct connection and cooperation with one another is
`described in the publication entitled “AT&T V.32bis/V.32/
`FAX High-Speed Data Pump Chip Set Data Book” pub-
`lished by AT&T Microelectronics, December 1991, which is
`incorporated herein by reference. This AT&T data pump
`chip set comprises the core of an integrated, two-wire full
`duplex modem which is capable of operation over standard
`telephone lines or leased lines. The data pump chip set
`conforms to the telecommunications specifications in
`CCITT recommendations V. 32bis, V. 32, V.22bis, V22,
`V23, V21 and is compatible with the Bell 212A and 103
`modems. Speeds of 14,400, 9600, 4800, 2400, 1200, 12,000
`and 300 bits per second are supported. This data pump chip
`set consists of a ROM-coded DSP16A digital signal proces-
`sor U2, and interface chip U1 and an AT&T T7525 linear
`CODEC U101. The AT&T data pump chip set is available
`from AT&T Microelectronics.
`
`The chip set U1, U101 and U2 on FIGS. 5A and 6B
`perform all A/D, D/A, modulation, demodulation and echo
`cancellation of all signals placed on or taken from the
`telephone line, and performs DTMF tone genera