Apparatus and method for a cellular freeway emergency telephone
Contents
1. o Ag Sa e Z ro enge 2 72 DO Q 74 ZId A 722 AS 4 788 711 Sheet 10 of 10 Nov 29 1988 US Patent O ANV XL 2 2 GOL A67 ZZ 08 SNG OST OGY 261 j b r za AY 24 ACH E SIO NO LOV 06 NIKO T NZH Mr amp 86 208 Gos Xu 4 788 711 1 APPARATUS AND METHOD FOR A CELLULAR FREEWAY EMERGENCY TELEPHONE SERVICE BACKGROUND OF THE INVENTION 1 Field of the Invention The invention relates to the field of cellular telephone equipment and in particular to solar powered telephone call boxes using a cellular telephone system to radiotele phonically communicate from a plurality of fixed road side sites 2 Description of the Prior Art Emergency roadside call boxes have become increas ingly important and productive elements in providing roadside security and emergency assistance in the met ropolitan areas in the United States and throughout the world Originally such roadside emergency call boxes were hardwired to conventional telephone land lines However the installation of such telephone land lines substantially escalates the installation and maintenance costs of such emergency roadside telephone boxes In order to overcome this limitation the prior art devised emergency telephone call boxes which use a radio transmission link for communications Cannalty et al Emergency Communications System U S Pat No 3 939 4172. SANNAL GIT 9 5 T DENEN dosez2044 SNWOILVIITISO NO LV2 NT WVVO2 IHOA 2LLVIAZHOS WILSAS A 7 39NVHJY3 AIHLO Woeds OL WILSKS WO23 731 gv 7 727732 U S Patent Nov 29 1988 Sheet 20f 10 4 788 711 US Patent Nov 29 1988 CELLULAR CALL BOX CONTROLLER CELLULAR TRANSCE VER Sheet 3 of 10 4 788 711 Nov 29 1988 Sheet 4of10 4 788 711 U S Patent XH ASO 72 AST YUMd SNVYL UMI SNVUL c 38779 LVF 00 ISING LVA 07 LAS Ast ASt AS 1Vg J Z v y D 5 Avg 077 NI oe gs 07 s hs BF A S Z PS ag DALEY U S Patent Nov 29 1988 Sheet50f10 4 788 711 SCT BSY BSY Fb 6 U S Patent Nov 29 1988 Sheet6of10 4 788 711 124 5v 144 146 z A12 De y D Ea 46 DMR I 24V 150 ASV ADDRES DRESS Ha 7 WF HIC DWA 40 BAT BSY TRANS PWR OFF BAT IN USE NL DATA BUS 116 IO BUS 4 788 711 Sheet 7 of 10 Nov 29 1988 US Patent LYE OT 72 Lva 07 135 NMG 72 NMO LIS ASE 72 AST LIS MH 416 72 MH 140 LAS W sna tzv gel NO LT2 704 N02 LYLYd MN Y KLIVO L Y VIVO Y LNOJ LM gH AG t D71 Sheet 8of10 4 788 711 29 1988 Nov US Patent SAT TO LNOP 4 788 711 Sheet 9 of 10 Nov 29 1988 US Patent OL a VO L EI Z xus Hi Gal Viv 2 p H H I C 1 Fe o VIVA M
3. Also mounted with antenna 32 is a solar panel 34 Solar panel 34 as described below is coupled to circuitry within main housing 28 and is used to recharge the batter included within the housing In particular solar array 34 is made of thirty four matched silicon solar cells with peak power rated at 10 5 watts The panel is glass laminated and held in a metal frame to protect it from dirt moisture and impact Approximately 2 2 watt hours per day is generated on the average by the solar panel 34 which is equivalent to the amount of power for 45 minutes of constant air time generally estimated to be equal four to five average roadside emergency calls Standard 30 is coupled to a ground anchor 36 to embed it into the site Ground anchor 36 and standard 30 are coupled together by brake plate 38 seen in FIG 2 so that if a vehicle collides with standard 30 brake plate 38 will bend retain standard 30 to the ground anchor 36 and allow standard 30 to be folded over instead of being snapped over the hood and thrust through the windshield of the oncoming vehicle Stan dard 30 is generally U shaped so that the coupling an tenna and power lines between housing 28 and solar array 34 antenna 32 are laid in the U shaped channel of standard 30 and can be covered or weather sealed by protective plate 35 The entire unit therefore comprises a sealed and weatherproof assembly The three watt cellular transceiver enclosed within main housing 28 is a co
4. ceiver if desired However in the present embodiment these control ports are not specifically used for the Motorola transceiver illustrated Returning to FIG 7 output PB1 of microprocessor 166 to be described below is also coupled to an input output bus 138 PB1 is coupled from input output bus 138 to an inverter generally denoted by reference nu meral 140 The inverted PB1 signal is applied to node 142 as the signal SVC service indicating that the transceiver has established radiotelephone contact with a ground station The signal SVC is then coupled to one of the inputs of encoder 114 and used as a condi tional signal to generate the eight bit status words cou pled from encoder 114 to data bus 116 The output PB7 of microprocessor 166 to be de scribed below is similarly coupled to input output bus 138 to an inverter generally denoted by reference nu meral 152 Output 154 from inverter 152 is the inverted signal IN USE which is used to signify that a call has been placed or is in process Thus IN USE similarly can be used as a conditional signal in decoder 114 to prevent inappropriate transmission of a status word to data bus 116 Encoder 114 is also coupled to the two highest ad dress bits A11 and A12 from address bus 124 through a series of logic gates generally denoted by reference numeral 144 More particularly A12 is inverted by inverter 146 and coupled together with address signal All to the inputs of NAND ga
5. In the illus trated embodiment call box 10 incorporates a twenty four hour flag If a twenty four hour interval has not expired since step 224 was last gueried the processing will return to step 210 If on the other hand twenty four 5 20 25 30 35 40 45 50 55 65 16 hours have elapsed since the last query at step 224 a call report status routine is entered at step 226 At step 226 microprocessor 118 will enter a predetermined subpro gram to telephone the central processing unit regarding the status of call box 10 Thus every twenty four hours or on any other arbitrary schedule each call box will call the central processing center identify itself and report its current status or even a past log of activity Many modifications or alterations may be made by those having ordinary skill in the art without departing from the spirit and scope of the invention For example the operational routine described at FIG 10 is illustra tive only and any other means could be arbitrarily pro grammed into execution It is to be expressly under stood that a different cellular transceiver such as an OKI model UM 1043B manufactured by OKI Electric Industries Co Ltd of Atlanta Ga could be easily sub stituted for the illustrated Motorola transceiver with appropriate modifications to accommodate the substitu tion according to well know design principles Furthermore it should be noted in connection with the circuit
6. and Wisniewski Emergency Calling Sys tem U S Pat No 3 492 581 show such systems Power for these call boxes is provided by a recharge able battery included within their housings However such prior art battery operated systems either required the units to be coupled to a source of electrical power for trickle charging or required the periodic replace ment or recharging of the battery packs through mobile roadside service A gain although savings were realized in installation costs by using battery powered units the maintenance or service costs of such systems often pro hibited their use Furthermore in the past radiotelephone communica tions within geographic areas were realized using a process based on a single transmitter and antenna This method of communication limits the number of calis that can be placed in a geographic area and limits the size ofthe area that can be covered with a given amount of equipment However with the recent advent of cel lular telephone technology these limitations which were characteristic of the prior art single transmitter systems no longer exist Therefore what is needed is a design and method of using a radio linked emergency call box which is adapt able to cellular telephone technology and which is char acterized by low installation and service costs BRIEF SUMMARY OF THE INVENTION The invention is a system for providing an emergency call box service comprising a plurality o
7. T DATA is also coupled to input port PB4 of microprocessor 166 C DATA and buffered T DATA output from gate 170 are provided as the inputs to exclusive OR gate 172 The output of gate 172 is thus true whenever T DATA or C DATA are true but if in an idle state they both go true the output is false Thus the output of gate 172 is true whenever data is being transmitted on the three wire bus and is false when the bus is in the idle state or reset state The out put of gate 172 is provided as an input in turn to exclu sive OR gate 174 whose other input is coupled to an interrupt port PB3 of microprocessor 166 The output of gate 174 is coupled to the inverted interrupted termi nal INT of microprocessor 166 This terminal will be active whenever data is being received from the trans ceiver PB3 port acts as an internal acknowledgement signal The output of gate 172 will be low when the data link is idle and will be high when it is busy Therefore when PB3 is high the inverted interrupt INT will go active low when data comes in This will cause an inter rupt to be executed in microprocessor 166 to enable it to receive data Finally R DATA is similarly coupled to the output of transistor 178 Transistor 178 is in turn driven by output PBO which is the data output from microproces sor 166 to transceiver 44 An input of exclusive OR gate 176 is also coupled to the output of transistor 178 and gate 176 acts as a buffer Therefore the output
8. decoder 130 FIG 8 for the control of these status circuits and control signals which are utilized in a decoder tree in FIG 9 to provide key pad and other cellular control signals to cellular telephone transceiver 44 Input and output to cellular telephone transceiver 44 is completely effectuated by the keypad signals shown coupled to the input output bus in FIG 9 and by the digital signals C DATA T DATA and R DATA described below in connection with microprocessors 118 and 166 Cellular telephone transceiver 44 commu nicates with microprocessor 118 through a second or interfacing microprocessor 166 described in FIG 10 Both microprocessors 118 and 166 control the transmit and receive audio level control circuitry shown in FIG 11 The overall operation of microprocessor 118 is sum marized by the flow chart of FIG 12 Turn now to FIG 5 wherein the operation of these functions can be provided by the circuitry illustrated FIGS 5 7 are schematics of several circuits which are controllably used to sense a number of status conditions of call box 10 For example the charged condition of battery 46 the physical integrity of call box 10 the presence of information on the communication channel the status of handset 40 and the condition of the trans mitter are all monitored and selectively reported by means of the circuitry which will now be described in connection with the following Figures Consider first the battery condition circui
9. generally referenced by numeral 184 The output of audio ampli fier 184 is coupled through coupling capacitor 186 and provided as an output at node 188 as the transmitted audio TX AUDIO ON OFF is a toggle signal on I O bus 138 as de scribed in FIG 7 and is similarly coupled through limit ing resistor 190 to node 188 to override the transmitted audio signal according to microprocessor 166 to cause the transceiver to be turned on or off Thus grounding the on off line at I 0 bus 138 causes the transceiver power to be turned on if it is off or to be turned off if it is on Similarly audio volume control or a gain adjust sig nal GAIN ADJ is provided from I O bus 138 through signal PA7 of microprocessor 166 This is a gain adjust signal coupled through transistors 190 and 192 thereby biasing node 194 at the input side of audio capacitor 182 to a point appropriate with the desired audio gain Thus the remote central controller can advise call box 10 to turn up the microphone volume as needed through the manipulation of the T and C DATA signals coupled to microprocessor 166 which then appropriately generates the gain adjust signal PA7 Similarly the received audio from the remote central operator is coupled to terminal 196 Again the received audio signal is coupled through an audio capacitor 198 into an audio amplifier generally denoted as reference numeral 200 The feedback of audio amplifier 200 in turn is controlled through the tr
10. information will be displayed on the screen in response to an automatic call distributor processor 22 coupled with a master processor 24 which causes specific infor mation to be brought up from the data base to the ap propriate support station 20 Such information includes the location of the call box nearest access roads local terrain and appropriate local emergency numbers Sup port station 20 and master processor 24 interactively communicate so that all subsequent actions which are 4 788 711 5 undertaken by the operator can be logged for archival management and planning use Archival discs 26 are coupled to and controlled by master processor 24 for mass data storage Turn now specifically to call box 10 as shown in FIG 2 in front elevational view and in FIG 3 in side eleva tional view Call box 10 is a completely self contained unit requiring no connection with external power lines or telephone cables Box 10 is solar powered is de signed for use with a cellular telephone system and is characterized by low cost installation with quick repair or replacement As shown in FIGS 2 and 3 call box 10 comprises a housing 28 mounted on a road standard 30 Housing 28 includes the call box controller radio transceiver and battery described and shown diagrammatically in the following Figures The three watt radio transceiver is coupled to a conventional collinear antenna 32 with 3 dB of isotropic gain mounted on the top of standard 30
11. of buffer gate 176 is the signal R DATA which is applied to input port PB2 for the purposes of timing Consider briefly the timing protocol used on the three wire bus Normally the bus is in a reset state i e C DATA and T DATA are both false When either one changes microprocessor 166 will be interrupted The message appearing on the T DATA line contains a bus direction field destination address field and data field When microprocessor 166 initiates communication R DATA data will go low indicating a reguest from pro cessor 166 A logic unit in the transceiver will establish bus direction and will expect to receive a message on the R DATA line The message then display on R DATA includes a source address field destination field and data field When the reguest for service is answered by the transceiver processor 166 will read the R DATA line and the destination address field of the incoming message Processor 166 will place a first bit of R DATA on the line at the start of a data state During communication initiated by the transceiver the first data bit will appear on the R DATA line after the bus goes from the reset state to the data state The remaining data will appear on the R DATA line during the idle state to data state transition period The last data bit of the message will be held on the R DATA line a few micro seconds after the T DATA and C DATA lines have returned to the reset state to allow the bit to be read by the contro
12. output O is the signal DWN down representing that the pole is down The clock input CP is the signal SET DWN set down and 4 788 711 9 latch 64 is cleared at its clear terminal CD by the signal CL DWN clear down Turn now to the circuitry in FIG 5 used to monitor the status of the rf transmitter When transceiver 44 is turned on 9 volts are applied to node 72 This in turns on transistor 74 whose output is coupled through in verter 76 to provide the signal inverted TRANS PWR transmitter power indicative that the transmitter is powered up Again TRANS PWR is used in circuitry to be described below as a status signal indicative of the operation of call box 10 Consider now the circuitry in FIG 5 used to selec tively power up the rf transmitter which as a primary power user is normally off A signal RLY ON relay on generated by means described below is applied to a Darlington pair generally denoted by reference nu meral 94 to selectively energize a relay 96 When relay 96 is energized in response to RLY ON the 13 volts of power at node 50 is coupled through contacts 98 to a plurality of power terminals IGN SENSE BAT PLUS BAT PLUS TRANSCEIVER POWER utilized else where in the circuitry as an operative means of power ing up transceiver 44 These power voltages are particu lar to the Motorola transceiver assumed in the illus trated embodiment and are thus not further discussed here Turning your attent
13. respect to memory 120 is conventional and will not be further detailed beyond that just outlined At any rate memory 120 is appropriately strobed and stored information is then read from outputs Q0 Q7 onto data bus 116 The signals data strobe DS and the read write signal R W from microprocessor 118 are similarly coupled to the inputs of NAND gate 128 whose output then serves as an output enable signal coupled to the inverted out put enable terminal of EPROM memory 120 Thus data from memory 120 as well as encoder 114 is appropri ately made available to microprocessor 118 over data bus 116 Outputs PAO PA7 and PBO PB7 are input output ports of microprocessor 118 which in the present em bodiment are used only as output terminals which are selectively accessed through a program control Con sider now the various outputs provided at these termi nals PAS PA7 and PB5 PB7 are coupled to the inputs of decoder 130 The signals at the outputs of PAS PA7 correspond respectively to two encoded bits designated as AQA and AIA and an inverted enable signal EA Similarly signals PB5 PB7 include respectively two encoded bits AOB and A1B together with an inverted enable signal EB These data bits and their respective enable signals are thus coded according to conventional means into a plurality of control signals as illustrated in FIG 6 For example the signals CL OFF HK SET 4 788 711 11 BSY CL BSY SET DWN CL DWN SET LO BAT and CL
14. the call box in response to the received off site information The controller comprises a circuit for conserving power from the battery when an emergency communi cation is not desired and a circuit for adjusting audio gain for audio information transmitted and received by the call box The invention can still further be characterized as a method in an emergency roadside call box where the call box is battery powered and coupled through a ra dio telecommunication link to a cellular telecommuni cation system and communication applications proces sor The method comprises the steps of reading a plural ity of call box status parameters Next follows the step of selectively performing a remedial routine in response to the step of reading the plurality of status parameters dependent upon the condition of each corresponding parameter Thereafter follows the step of selectively entering an emergency call routine wherein a cellular telecommunication transceiver within the call box is powered up and bidirectional voice communication is established through the cellular telecommunication system to the communication applications processor By virtue of this method remotely powered emergency call boxes in radio telecommunication with the commu nication applications processor are operationally main tained The invention can still further be characterized as an apparatus in combination with a cellular radiotelephone for generating information compat
15. LO BAT which were described in connection with various status latches of FIG 4 are generated by microprocessor 118 in combination with decoder 130 The various latches are thus clocked and cleared at the appropriate times under software control as the status of call box 10 queried Outputs PA0 PA4 of microprocessor 118 are cou pled to a control bus 132 to respectively generate con trol signals AO A4 whose use will be better described in connection with FIG 10 in relation to the manipulation of transceiver 44 The output of PBi of microprocessor 118 which is active low is coupled to an inverter 134 whose output 136 is a signal RLY ON used to power Darlington pair 94 in FIG 5 in order to power up transceiver 44 PA7 PB7 and PB are each pulled high through a resistor in the case where the lines float so that decoder 130 and the transceiver power up relay are affirmatively maintained disabled unless clearly pulled active low by an appropriate output on each of these lines The outputs of PBO PB3 of microprocessor 118 are the signals return data transmit R DATA T receive data receive R DATA R true data receive T DATA R and inverted interrupt control INT CONT which are specific input and output control signals used to provide necessary control functions for transceiver 44 Coupling directly to the input output ports PBO PB3 of microprocessor 118 gives the microprocessor the ability to directly respond to and to manipulate a trans
16. United States Patent 19 Nasco Jr 54 APPARATUS AND METHOD FOR A CELLULAR FREEWAY EMERGENCY TELEPHONE SERVICE 75 Inventor Michael Nasco Jr Laguna Hills Calif Cellular Communications Corporation Houston Tex 21 Appl No 801 410 73 Assignee 22 Filed Nov 25 1985 51 Int CEF nn H04M 11 00 52 U SCE essen 379 59 455 33 455 313 379 63 58 Field of Search 379 56 59 60 455 33 455 89 100 56 References Cited U S PATENT DOCUMENTS 3 844 840 10 1974 Bender 136 89 4 176 254 11 1979 Tuttle et al 179 5 R 4 219 698 8 1980 Birilli et al 179 5 P 4 577 182 3 1986 Millsap et al 340 539 4 639 914 1 1987 Winters wee 370 110 1 4 724 538 2 1988 Farrell 379 59 Primary Examiner Robert Lev CELLULAR TELECOM o SYSTEM 44 MOBILE TELEPHONE SWITCH ING OFFICE END OFFICE LOCAL TELEPHONE EXCHANGE CARRIER TO FROM OTHER EACHANGE lt TO FROM INTER EXCHANGE CARRIERS APPLICATIONS PROCESSOR pa 4 788 711 Nov 29 1988 11 Patent Number 4 Date of Patent Attorney Agent or Firm George F Bethel Patience K Bethel 57 ABSTRACT A self contained cellular emergency roadside call box is disclosed without the use of external telephone lines The call box is solar powered with battery storage and comp
17. a sidestep VCO on the syntheziser board The output of the VCO a modu lated 30 MHz signal is coupled to a buffer whose out put is coupled to one input of a sidestep mixer The injection input on the mixer is provided with a signal which is an output freguency doubled from the receive VCO The output of the mixer is a modulated RF sig nal The RF signal is then coupled through a 3 pole filter and amplifier before being coupled to a RF power amplifier The freguency synthesizer comprises a receiver VCO a synthesizer digital board and an exciter board The operating frequencies in the radio are all derived from the receiver VCO phase locked loop This is com prised of a dual modulus prescaler a programmable PLL IC a charge pump loop filter and receiver VCO hybrid This loop is controlled by a channel select line from the logic circuitry which serially loads the channel select data into the programmable PLL IC One output of the receiver VCO goes through a frequency tripler and is fed to the injector doubler hybrid used in the first mixer of the RF receive circuitry The other output from the receive VCO is coupled to a frequency dou bler on the exciter boar and serves as the input signal to the sidestep mixer Further details and schematics of all the above cir cuitry can be found in the Motorola User s manual referenced above The transceiver signals which are referenced most often in the disclosure of the illustrated embodiment ar
18. annel is the stron gest cellular channel available This selection of com munication channels by transceiver 12 and mobile tele phone switching office 14 is well known in the art of cellular communications and will not be further de scribed Local cell site transceiver 12 is connected with a mobile telephone switching office 14 by wireline trunks Mobile telephone switching office 14 which is an automatic terminal then provides call box identity confirmation and predialed access to the control center which includes a communications applications proces sor generally denoted by reference numeral 16 Mobile telephone switching office 14 can also connect call box 10 to a conventional telephone switching exchange 15 in response to commands from the control center so that three party telephone conference calls can be provided or the call from call box 10 simply handed off to another telephone station The incoming calls will be uniguely identified with a specific emergency call box The identification will then be used to access a data base and all information corre sponding to that call box will be retrieved in the appli cations processor 16 An automatic call distributor 18 will connect the incoming call to an available operator at a communications applications processor CAP sort center 20 A human operator answers the call and the communication which to this point has been digital will be followed by voice communication Specific call box
19. ansistor 202 by means of the gain adjust signal GAIN ADJ acting through the output transistor 190 Therefore the received audio gain coupled to input 204 of differential amplifier 206 can be remotely operator adjusted through gain adjust signal GAIN ADJ The output of differential amplifier 206 in turn is coupled to the input of a push pull ampli fier generally denoted by reference numeral 208 The output of push pull amplifier 208 is coupled as the op posing input to differential amplifier 206 thereby main taining the output 210 of differential amplifier 206 at a continual maximum The output of push pull amplifier 208 is in turn resistively coupled through audio capaci tor 212 to the receiver or ear piece terminals 214 in hand set 40 Solar array 34 is also coupled to battery 46 through controller 42 by means of a shunt regulator The regula tor is conventional and thus is not further shown in the Figures Coupling through the shunt regulator prevents overcharging of battery 46 and thereby eliminates the 4 788 711 15 potential of any damage due to overvoltages or over charging The circuitry now having been generally described in connection with FIGS 4 9 turn to the flow diagram of FIG 12 which illustrates the basic operation of control ler 42 Upon power up as indicted by step 201 a master reset signal is generated to program control at step 203 to reset all chips within the circuit This step generates any logic reset si
20. atically powering the transceiver when handset 40 is lifted 3 automatically dialing the preprogrammed number or alternatively any one of a plurality of numbers corre sponding to one of a corresponding plurality of acti vated switches or buttons not shown in the Figures 4 automatically powering down after a preset pre programmed time period or after hang up of handset 40 5 controlling and adjusting necessary voltage level changes in audio and logic circuits 6 controlling and regulating all timing functions to integrate the various portions of the assembly 7 controlling and regulating the recharging rates from solar array 34 8 controlling all power for the entire assembly de picted in FIG 4 in a manner designed for the most efficient conservation and use of power 9 interfacing to transceiver 44 and 10 15 20 25 30 35 40 45 50 65 8 10 providing necessary logic and interface for op tional controller functions and future enhancements such as slow scan video or specialized data links Controller 42 is built around a microprocessor 118 described in connection with FIG 8 A number of sig nals indicative of the status of call box 10 are coupled to a data bus 116 as described in FIG 7 to which micro processor 118 is coupled and are generated by a plural ity of status circuits described in FIGS 5 and 6 Micro processor 118 generates a number of discrete control signals through a
21. bcircuit monitors a predetermined Status parameter of the corresponding call box The system further comprises a circuit for selectively communicating the predetermined parameters as moni tored by the plurality of status subcircuits to the com munication applications processor The parameters monitored by the status subcircuits include battery power level and the physical condition of the corre sponding call box indicative in part of whether call box has been struck The controller further comprises a circuit for receiv ing and processing information from the communica tion applications processor to initiate operations in the controller The controller still further comprises a circuit for adjusting the volume of transmitted and received audio information The controller has a timing mechanization included within its digital circuitry The timer provides the capa bility to measure predetermined elapsed time periods The timer mechanism is used in the following ways 1 To limit each call to a maximum duration e g 10 minutes 2 To terminate a call if there is no conversation for a predetermined period of time e g one minute and 3 To cause each call box to automatically initiate a call and to report its operational status on a periodic basis e g once every 24 hours In the event that the telephone handset is left off the hook the automatic time out will terminate the call and will thus save battery power Should this o
22. cation processor or cellular telecommunication 15 20 25 30 35 45 50 55 65 18 system to selectively perform a remedial routine in response to said step of reading said plurality of status parameters dependent upon the condition of each corresponding parameter in order to render said call box operational selectively receiving said information at said plurality of call boxes selectively entering an emergency call routine wherein a cellular telecommunications transceiver within said call box is powered up and bidirectional voice communication is established through said cellular telecommunication system to said commu nication applications processor whereby remotely powered emergency call boxes in radiotelecommunication with said communication applications processor are operationally main tained 9 The method of claim 8 further comprising the step of selectively reporting said plurality of status parame ters from each said call box through said cellular tele communication system to said communication applica tions processor i 10 An apparatus in combination with a cellular radio telephone for generating information compatible with said cellular radiotelephone in an emergency call box comprising first means for determining a plurality of status condi tions relating to said emergency call box second means for controlling power usage of said emerency call box to minimized power usage and third mea
23. ccur the call box is automatically reactivated and another emergency call is placed should the hook switch be operated to the on hook status followed by an off hook status Stated in yet another way the invention is an emer gency roadside call box comprising a controller a cel lular transceiver coupled to and controlled by the con troller a battery for powering the controller coupled to the controller and transceiver and a solar array coupled to the controller for recharging the battery By reason of this combination of elements an emergency roadside call box can be installed and maintained at low cost The controller comprises a plurality of status subcir cuits for monitoring corresponding selective parameters of the controller and a circuit for interrogating the plurality of status subcircuits for operationally respond ing to the parameters as monitored by the status subcir cuits The plurality of the subcircuits comprise at least a subcircuit for monitoring a user request for emergency transmission battery condition presence of a communi cation transmitted to and from the call box physical integrity of the call box 4 788 711 3 The call box further comprises a circuit for selec tively communicating the corresponding plurality of parameters of the call box to an off site recipient The call box still further comprises a circuit for re ceiving information generated off site and a circuit for initiating an operation of
24. der stood as being provided only for the purposes of exam ple and clarity and not as a limitation of the invention as defined in the following claims I claim 1 A system for emergency call box service compris ing a plurality of emergency call boxes wherein each call box further comprises a controller a cellular trans ceiver coupled to said controller a battery coupled to said controller for providing power to said con troller and transceiver and means for generating power coupled to said controller for recharging said battery and cellular telecommunications subsystem in radio telecommunication with each of said plurality of emergency call boxes said cellular transceiver being remotely progammable said controller for programming operation of said cellular transceiver in response to information receivied from said cel lular telecommunications subsystem wherein said 4 788 711 17 controller further comprises means for receiving and processing information to initiate operations in said controller whereby said plurality of emergency call boxes can be installed which are capable of arbitrarily pro gammable interactive operations 2 The system of claim 1 further comprising inter office local telephone exchanges coupled to said plural ity of call boxes wherein communication between said cellular telecommunication subsystem and said plurality of call boxes is selectively coupled through said inter office local telephone e
25. diagrams of FIGS 4 9 that call box 10 incor porates a digital address bus data bus control bus and 1 0 bus Therefore it is entirely within the scope of the art that such generalized bus structures can be em ployed with other digital circuitry to expand the opera tional capacities of call box 10 For example a slow scan video circuit can be appropriately coupled to the buses if desired to provide visual information of traffic condi tions at selected points In addition a data telemetry input subcircuit can similarly be coupled to the buses of call box 10 to allow for example for the transmission of digital medical data by paramedical emergency teams who may be attending an accident victim near the site of a call box Such emergency medical data could be radio telemetered from the accident site to the nearest call box which would then retransmit to the nearest hospital without the necessity of lifting hand set 40 off the hook or other direct wire coupling to the call box The call box could similarly be time share with environ mental sensing and reporting systems Virtually any device which could benefit from a remote communica tions device could be easily combined and accommo dated by the open bus structure of the invention The adaptability of the invention is even further enhanced when it is realized that interactive digital and voice communications is facilitated through call box 10 Therefore the illustrated embodiment must be un
26. e the handset signals The handset includes a cradle mi croprocessor which provides an interface between the microprocessor of the handset and the microprocessor of the transceiver logic unit Digital communication is effectuated through the digital signals C DATA T DATA and R DATA Data carried by the bus conven tion include keypad and fluorescent display information 4 788 711 7 for the handset display information for the cradle con trol indicator board and other various control signals and commands between the control unit and transceiver logic unit Only the more relevant of these signals will be discussed below Logic gates are provided in con junction with the bus signals to gate either timing infor mation or data depending on the state of a control line INT SELECT The handset processor uses this cir cuitry to determine if the information on the T DATA line is actual data or merely a timing pulse C DATA and T DATA or C DATA and R DATA the choice depending on the direction of information flow will be logical complements during data transmission When they are not so related they will signify timing informa tion i e the reset or idle states Communications with these signals is on a three wire bidirectional bus Data is communicated in an address then data serial word for mat At the beginning of communication the bus direc tion is established During message transmission each data state is followed by an idle state wi
27. ead the status data 20 40 45 50 55 60 65 4 FIG 8 is a schematic diagram of a programmabie microprocessor incorporated in the controller FIG 9 a schematic diagram of decoder circuit used to communicate between the microprocessors on the controller FIG 10 is a schematic diagram of a circuit for cou pling signals between the transceiver and one of the microprocessors on the controller FIG 11 is a schematic diagram of an audio level adjust circuit which can be controlled by a remote central processor FIG 12 is a flow diagram illustrating the operation of the controller The invention and its various embodiments may be better understood by now turning to the following de scription DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Before considering the detailed circuitry in the cellu lar call box and its method of operation first generally consider the environment in which the call box is used and how it is utilized during normal operation Turn now to FIG 1 When an emergency occurs along a roadside the affected user will locate the near est emergency call box generally denoted by reference numeral 10 The user will lift the handset which will cause call box 10 to automatically dial a prepro grammed number to the freeway emergency telephone system control center The call is transmitted via a radio link to a local cell site transceiver 12 over a selected one of 21 channels according to which ch
28. econd column to the signal END and in third column to the signal SND Included as discrete signals are the control signals volume VOL and power PWR which are also refer enced in FIG 9 as the input output signals on bus 138 as VOL CONT and ON OFF respectively Each of the row and column signals from switches 158 164 are active low and are appropriately buffered and coupled through diodes and resistors according to conventional principles as illustrated in FIG 9 to I 0 bus 138 By this means microprocessor 118 can arbitrarily manipulate and control radiotelephone transceiver 44 Turning how to FIG 10 a microprocessor 166 run by crystal controlled clock 168 allows signals received by transceiver 44 to place signals of the input output bus 138 Microprocessor 166 interfaces the circuitry and buses described above with ihe unique signals used by transceiver 44 and to that extent is transceiver depen dent The signals return data R DATA complemen tary data C DATA and true data T DATA are signals specific to the Motorola transceiver 44 and are digital signals which are transmitted between transceiver 44 and the controller 4 788 711 13 Each of these signals is coupled through appropriate logic circuits to input ports of the microprocessor 166 For example T DATA an input signal to microproces sor 166 is coupled through an exclusive OR gate 170 acting as a buffer since one input is held low The output of gate 170 which is
29. essor 118 will then read the various status signals as step 211 as described in connection with FIG 8 Should the pole down signal DWN for exam ple be active as determined at step 213 processor 118 will then enter a specialized down routine at step 215 to take whatever appropriate remedial action or reporting as is desired in the case that the call box has been run over or otherwise down on the ground After the down routine is completed or there is no pole down situation processor 118 then determines at step 216 whether the battery level is low If the power is low it enters a power subroutine at step 218 and performs any remedial action necessary in response to low battery such as unconditionally disabling the trans ceiver 44 Again after execution of the low power routine or if the power is adeguate microprocessor 118 will then inguire at step 220 whether an emergency call is being placed If an emergency caller is placing a call by lifting hand set 40 off the hook an emergency call routine is entered at step 222 wherein transceiver 44 is powered up a predetermined phone number is dialed or transmitted together with specific identifying informa tion uniguely identifying call box 10 After the call is completed the processing again returns to step 210 where the status is reread If at step 220 an emergency call is not being placed an inquiry will be made at step 224 as to whether or not a predetermined time interval has passed
30. f emergency call boxes wherein each call box further comprises a controller a cellular transceiver coupled to the control ler a battery coupled to the controller for providing power to the controller and transceiver and a solar array for generating power coupled to the controller for recharging the battery Also included in the system is a cellular telecommunications subsystem in radio telecommunication with each of the plurality of emer gency call boxes A communication applications pro cessor is coupled to the cellular telecommunications subsystem for processing data received in part from the plurality of emergency call boxes The communications applications processor communicates through the cellu 10 15 20 25 30 35 40 45 50 55 60 65 2 lar telecommunications subsystem with selected ones of the plurality of emergency call boxes By reason of this combination of elements the plurality of emergency call boxes can be installed and maintained at low cost and are capable of arbitrarily programmable interactive operations The system further comprises interoffice local tele phone exchanges coupled to the communication appli cations processor wherein communication between the plurality of emergency call boxes can be selectively coupled to the local telephone exchanges under control of the communication applications processor The controller comprises a plurality of status subcir cuits Each status su
31. gnals reguired by the microprocessors 118 or 166 or any other logic circuitry In addition during this step the transceiver may execute any initial protocol operations For example in the case of the Motorola transceiver of the illustrated embodiment the best ground station or forward control channel is se lected Service is then established between the selected forward control channel and the cail box The trans ceiver or microprocessor 118 then dials a prepro grammed telephone number and sends identifying codes which establish the call box s identity These numbers and codes are verified and then communications is se lectively established on a reverse channel when appro priate All this is protocol which is normally handled by the cellular transceiver and ground station and do not strictly affect the operation of the invention as de scribed here Thereafter the outputs of each of the status chips are set to zero or initialized at step 205 This corresponds to the generation of various set signals shown as the output of decoder 130 and as described in connection with the latches of FIG 8 Having cleared and set each of the status latches processor 118 then enters a self test program to test the contents of memory 120 at step 207 Each self test pro gram is checked a predetermined plurality of times at step 209 The test is repeated until it successfully passes or a timeout occurs Upon successful self testing of memory 120 proc
32. ible with the cellular radiotelephone in a solar powered emergency call box The invention comprises a first circuit for determining a plurality of status conditions relating to the emergency call box a second circuit for controlling power usage of the emergency call box to minimize power usage and a third circuit for processing the status conditions deter mined by the first circuit and responsive to at least the status conditions controlling the second circuit The third circuit also selectively bidirectionally generates and receives cellular radiotelephone compatible signals under programmable control The third circuit is cou pled to the first and second circuit and to the cellular radiotelephone The invention is best understood in the context of an illustrative example as shown in the following drawings wherein like elements are referenced by like numerals BRIEF DESCRIPTION OF THE DRAWINGS FIG 1 is a block diagram of a system in which the call box incorporating the invention is included FIG 2 is a front elevational depiction of the call box as installed at a roadside site FIG 3 is a side elevational view of the call box of FIG 1 FIG 4 is a block diagram of including the controller in the call box and its associated system elements FIG 5 is a schematic diagram of status subcircuits included in the controller FIG 6 is a schematic diagram of another status sub circuit FIG 7 is a schematic diagram of a circuit to r
33. igits 0 9 and and two additional related radiotelephone signals ON OFF and volume control VOL CONT Thus bits A0 A3 represent sixteen possi ble combinations with a four bit word which is decod ed in two stages in decoders 154 and 156 and coupled as sixteen discrete output signals to the inputs of analog Switches 158 164 The A4 bit either disables all sixteen outputs or enables the one of sixteen outputs as desig nated by the A0 A3 bits Consider for example analog Switch 164 The four inputs to analog switch 164 correspond to the key pad numerals 0 3 With respect to each of these numerals two signals will need to be generated in order to command transceiver 44 namely the row and column designations corresponding to key pad numbers 0 3 In particular numeral 0 is located in the second column and fourth row Therefore the first two outputs of analog switch 164 correspond to col umn 2 row 4 and will be activated in response to activation of one of the inputs to analog switch 164 such as E0 The pairs of outputs corresponding to numerals 1 2 and 3 are similarly activated In the same manner the outputs of analog switch 162 correspond to the row and column pairs corresponding to key pad numerals 4 7 Analog switch 164 similarly includes as its outputs key pad numerals 8 and 9 and The outputs of analog switch 158 are peculiar to radiotele phones which comprise a fifth row The fifth row on a radio telephone corresponds in the s
34. ion to the circuitry of FIG 6 consider now the status of the operation of handset 40 The audio portion of the signal from handset 40 is cou pled through capacitor 78 to a peak to peak detector generally denoted by reference numeral 80 The output of peak to peak detector 80 is coupled through a buffer generally denoted by reference numeral 82 to the set input SD of clocked latch 86 The output O of latch 86 is the signal BSY busy which indicates that infor mation conversation or at least an audio signal of some sort is being provided to handset 40 The clock input CP of latch 86 is the signal SET BSY set busy and latch 86 is cleared at its clear terminal CD by the signal CL BSY clear busy The means for originating various status signals now having been described the primary status ignal namely the lifting of the handset off its hook switch can be considered Conventional telephone hook switch 100 in FIG 5 senses the lifting of handset 40 One terminal of the switch 100 is coupled to ground and the remain ing terminal is coupled to a debounce NAND gate latch generally denoted by reference numeral 102 The output of latch 102 is the status signal OFF LAT off latch which is also used as a clocking signal for clocked latch 106 The input D of latch 106 is coupled to the 5 volt power supply so that upon receipt of a clock pulse OFF LAT output O of latch 106 the sig nal OFF HK off hook goes high Latch 106
35. is cleared at its clear terminal CD by a signal CL OFF HK clear off hook Thus once the handset has been taken off hook the circuitry will be able to remember that this has occurred even if placed back on hook until latch 106 is cleared by program control through CL OFF HK This allows the program to recognize that a call was attempted and to enter a call ready status for a predeter mined time regardless of the actual hook condition Turn now to FIG 7 The various status signals de scribed in connection with FIGS 5 and 6 OFF HK DWN LO BAT BSY TRANS PWR and OFF LAT are each provided as inputs to an encoder 114 The output of encoder 114 is coupled to a data bus 116 as a parallel 8 bit word described in more detail in connec 10 15 20 25 45 50 55 60 65 10 tion with FIG 8 The remaining portions of the cir cuitry of FIG 7 will be described below Turning to FIG 8 the encoded word in data bus 116 which is diagrammatically shown throughout the cir cuitry as appropriate is coupled to inputs B0 B7 of microprocessor 118 which is the operational pro grammed microprocessor of controller 42 Micro processor 118 in the illustrated embodiment is a Motor ola 6805 CMOS device which is characterized by very low power consumption Microprocessor 118 is clocked by a conventional external crystal controlled clocking circuit generally denoted by reference nu meral 119 The program for microprocessor 118 is
36. l unit During a communication initiated by processor 166 processor 166 will hold the first data bit on the R DATA line until T DATA and C DATA lines enter a data state at which time another bit is sent At the occurrence of each idle state processor 166 will read the R DATA line through gate 176 and compare it with what is being sent If there is a conflict processor 166 will stop sending and vacate the bus Processor 166 20 25 30 45 50 55 60 65 14 will reguest service again when the bus returns to the idle state Consider now the remaining output terminals of mi croprocessor 166 The outputs PCO PC2 correspond to columns 3 through column 1 of the key pad respec tively outputs PAO PA4 corresponding to rows 1 5 of the key pad respectively and signals PB1 or SVC ser vice and PB7 or IN USE described above can be selec tively generated coupled to input output bus 138 PA7 is a GAIN ADJ signal described below in connection with FIG 11 used to adjust audio signal strengths in the voice channel PC3 is coupled to a push button switch which can be manually operated by the call box user to step up the audio strength of the received voice commu nication Turn now to FIG 11 wherein the circuitry illustra tive of audio processing is illustrated The microphone input of hand set 40 is coupled across terminals 180 The audio signal for the caller is thereby coupled through coupling capacitor 182 to an audio amplifier
37. ns for processing said status conditions de termined by said first means and responsive to at least said second means said third means for selec tively bidirectionally communicating cellular ra diotelephone compatible signals said third means being coupled to said first and second means and to said cellular radiotelephone said third means being remotely programmable to selectively process said status conditions and to selectively communicate said cellular radiotelephone compatible signals and selectively communicate said cellular radiotele phone compatible signals and selectively operate said apparatus in response thereto k k
38. nventional Motorola cellular transceiver sold under the trademark DYNA TAK 2000 The details of operation of the transceiver are only implicitly included in this description and will not be expressly discussed except to the extent necessary for a fully illustrated description Further details of the transceiver of the illustrated embodiment can be found in the published user s manual entitled DYNA T A C Cellular Mobile Telephone 800 MHz Transceiver available from Motorola Technical Writing Services at 1301 E Algonguin Rd Schaumburg Ill 60196 which is expressly incorporated herein by reference Although details of the transceiver are incidental to the invention a general description is provided here for completeness of explanation First consider the receive circuitry of the transceiver In the transceiver discussed in the illustrated embodiment radio signals in a prede termined range are selected by a 6 pole bandpass filter The modulated receive signal is then passed to a pream plifier A 3 pole filter which further bandpass filters the receive signal is coupled to the output of the preampli fier A first mixer is coupled to the 3 pole filter An 20 25 35 40 45 so 55 60 65 6 injection signal is generated by a receiver synthesizer and mixes with the receive signal to provide a first IF signal The IF signal is then coupled to an IF board The IF signal 45 Mhz is coupled to a buffer amplifier whose
39. output is coupled to a 2 pole crystal filter which passes the signal on to a second buffer amplifier The output of this buffer amplifier is coupled to a second 2 pole filter The output of the second 2 pole filter is coupled to a circuit which includes a second mixer an IF amplifier a receiver signal strength indicator and a FM detector A second conversion and detection is executed in this circuit and its output is an audio signal which is coupled to an audio logic board On the audi o logic board the audio receive signal is conditioned in a conventional manner An audio signal from the handset is coupled to the radio via a transmit audio hybrid on the audio logic board This hybrid comprises a buffer and a 300 Hz to 3 kHz bandpass filter The output from the bandpass filter of the transmit audio hybrid is fed to a 2 1 compressor comprised of by one half of a single IC compander located on the audio logic board The compander dy namically condenses the audio signal which is ex panded 1 2 by the cell site controller to the original dynamic range The output of the compressor is fed back into the transmit audio hybrid which contains circuitry for preemphasis limiting filtering audio mut ing and a summing amplifier to combine the transmit audio signal with data supervisory audio tones and other control signals before outputting the signal to the synthesizer digital board The transmit audio signal is coupled to the modulation input of
40. rises a controller coupled to a cellular transceiver The controller is also coupled to a solar array and bat tery which is recharged through the controller The call box communicates through a radio telephone link estab lished by the cellular transceiver to a cellular telecom munication system The cellular telecommunication system includes a call site controller and mobile tele phone switching terminal Each call box comprises a plurality of status subcircuits for monitoring conditions such as battery condition and transmitter status The call box communication and the status are processed by a micro processor which generates appropriate com mands reguired by the cellular transceiver Information can be transmitted bidirectionally between each of the call boxes and the communication applications proces sor An interactive flow of information is exchanged with the call box and the functional condition is moni tored 10 Claims 10 Drawing Sheets SYSTEM SCHEMATIC COMMUNICATION MASTER PROCESSOR n OPERATING ROUTINES O SERVICE MODULES 4 788 711 Sheet 1 of 10 Nov 29 1988 U S Patent SITAGOW IHAGIS A gt S7MANOS PNILVYTSO SYTAYVI FONVHIXI ATLNI WOd1 01 FF JAN Casa Cg VV YTIUA VI FONVHINT INOHFFTTFL 77907 5M410 AN eos S 320td ez HOSSTFT204d WOILVIS LYOGENS SYN NEL 7110 ave INI HALIMS Foran woLng ef LS1G 3WOHd 1121 J7 g0W
41. stored within an external EPROM memory 120 Mem ory 120 is accessed by microprocessor 118 through terminals BO B7 and A8 A12 which provide a thir teen bit access word Terminals BO B7 are used during the first half cycle of processor 118 as the lower eight bits of the address and during the second half cycle as a data input output Therefore during the memory fetch the lower eight bits of the address are coupled through data bus 116 to a bit latch 122 under the control of the address strobe signal from terminal AS of processor 118 Thereafter all thirteen bits of the address are cou pled to address bus 124 The address inputs A0 A10 of memory 120 are thus coupled to address bus 124 and memory 120 enabled by address bits All and A12 through NAND gate 126 and strobed by the output of NAND gate 128 Memory 120 is selectively strobed in a read or write cycle according to software control through the read write terminal inverted R W and data strobe terminal DS of microprocessor 118 which are provided as the inputs to NAND gate 128 Upon power up and reset the internal address register of microprocessor 118 is set at the highest address of 2K EPROM memory 120 The program is stored in two kilobytes of memory Thus A12 and All are provided as the inputs to NAND gate 126 whose output is cou pled to the inverted chip enable terminal CE Thus the two highest address bits serve as an address enable The control and timing of microprocessor 118 with
42. t depicted in FIG 5 Battery 46 is coupled to node 50 A conven tional voltage regulator generally denoted by reference numeral 52 converts the 13 volts D C to 5 volts for use throughout the logic circuitry as indicated The battery voltage at node 50 is monitored by a conventional zener diode 54 If the voltage is sufficient transistor 56 whose input is coupled to the anode of diode 54 will be biased on and its output coupled through two inverters collec tively denoted by reference numeral 58 to the set input terminal SD of a clocked latch 60 The output O of latch 60 is provided with the signal inverted LO BAT low battery which is utilized in subseguent circuitry as described below Whenever LO BAT is true a pre determined low battery voltage or state of battery dis charged is indicated The clock input CP of latch 60 is provided with a signal SET LO BAT set low battery Latch 60 is cleared by a signal CL LO BAT clear low battery coupled to the clear terminal CD of latch 60 Consider now the circuitry in FIG 5 which monitors the physical condition of call box 10 namely whether standard 30 is down on the ground A mercury tilt switch 62 is coupled between the five volt supply and ground and is normally closed However should the pole be struck or otherwise tilted switch 62 will open as shown in FIG 5 When switch 62 opens a high or true signal will be coupled to the set terminal SD of clocked latch 64 whose
43. te 148 The output of NAND gate 148 is logically combined in OR gate 150 with the output of NAND gate 128 the inverted signal DS R The output of OR gate 150 in turn is coupled to the inverted output enable terminal OE of encoder 114 Therefore the output word from encoder 114 is coupled to data bus 116 according to the logic provided by gates 144 This logic prevents the placement of a status word on data bus 116 at the same time that the program is being read from memory 120 5 15 20 25 35 40 45 60 65 12 Turn now to FIG 9 wherein signals A0 A4 gener ated on control bus 132 by microprocessor 118 are con verted into row and column key pad signals which can be understood by transceiver 44 The signal A4 on con trol bus 132 corresponding to the output from terminal PA4 of microprocessor 118 is an enable signal used to enable decoder 154 Decoder 154 is driven by the con trol signals A2 and A3 corresponding respectively to terminals PA2 3 of microprocessor 118 The output of decoder 154 are intermediate inverted decoding signals EA and EB These signals are output in parallel to a second stage of two decoders 156 which have as addi tional inputs control bus signals A0 and A1 correspond ing respectively to terminals PA0 1 of microprocessor 118 Ultimately the five control bits A0 A4 will be converted into twelve key pad signals corresponding to the twelve buttons on a telephone key pad correspond ing to d
44. th a reset state entered after the last data bit of the message Further details of the bus protocol are described in the Motorola User s manual referenced above Keypad data is communicated from the handset via column and row signals which are then used with an internal look up table to identify the keypad button which was pushed Handset 40 is diagrammatically depicted in FIG 2 No further detailed discussion of the transceiver will be undertaken except to such extent as such details affect the operation of the cellular call box controller also included in housing 28 The controller is a single board circuit which can be easily removed from a modular pin connector and a new board inserted for easy field ser vice The controller comprises the logic and circuitry necessary to control the entire operation of call box 10 Turning to FIG 4 a diagrammatic depiction of the elements within call box 10 is shown Cellular call box controller 42 serves as the central unit to which solar array 34 battery 46 and any additional call box switches or input output functions 48 are coupled Similarly cellular transceiver 44 is coupled to controller 42 and antenna 32 in turn is coupled to cellular transceiver 44 Before describing the circuitry of controller 42 con sider first the functions which controller 42 performs Included among but not limited to these functions are 1 controlling operation seguences for user friendly adaptation 2 autom
45. xchanges 3 An emergency roadside call box comprising a controller means for receiving remotely originated information a remotely programmable cellular transceiver cou pled to and controlled by said controller operation of said cellular transceiver being initiated at least in part by said remotely originated information re ceived by said controller a battery for powering said controller coupled to said controller and transceiver and means coupled to said controller for recharging said battery 4 The call box of claim 3 further comprising a subcir cuit for monitoring a user reguest for emergency trans mission 5 The call box of claim 3 comprising a subcircuit for monitoring presence of a communication transmitted to and from said call box 6 The call box of claim 3 further comprising means for selectively communicating a plurality of parameters of said call box to an off site recipient 7 The call box of claim 3 wherein said controller comprises means of conserving power from said battery when an emergency communication is not desired 8 A method in an emergency roadside call box said call box being battery powered and coupled through a radio telecommunication link to a cellular telecommu nication system and communication applications pro cessor said method comprising the steps of reading a plurality of call box status parameters at a plurality of call boxes sending information from said communication appli
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