FORM2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention - SECURE COMMUNICATION OVER CAN FOR
FUEL DISPENSER

2. Applicant(s)
(a) NAME :
(b) NATIONALITY
(c) ADDRESS :

LARSEN & TOUBRO LIMITED
An Indian company
L & T House, Ballard Estate, Mumbai 400 001 State of Maharashtra, India

3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed :

FIELD OF THE INVENTION
The present invention relates to a fuel dispensing unit comprising of secure communication arrangement for connecting various sensing units and the main card of fuel dispenser More particularly the present invention is concerned about a secured communication arrangement in the fuel dispensing unit to provide long distance communication range with multi master functionality and data encryption thereby avoiding tampering.
BACKGROUND AND THE PRIOR ART
Conventional multi unit fuel dispenser systems comprise a main card connected to plural units of sensor means or modular cards. These modular cards did not have any intelligence and the entire logic was on the main card. Accordingly the connection between the slave card and the main card could be tampered. Further the design of the conventional fuel dispenser system was not modular.
US 6082618 discloses a system for identifying specific devices in the configuration wherein the multi product dispenser system includes a pump computer, a motor- valve drive board coupled to the pump computer, a sales display coupled to the pump computer, and a hardware identifier in each of the computer, motor-valve drive board and sales display for communicating with a software program in the pump computer. According the prior art, by providing hardware identification on each electronic assembly in the fuel dispenser, these intelligent devices can operate in harmony in the system without the need for manual step. This reduces errors and saves time when installing and repairing dispensers. However, it was not known in the prior art that by including a unique communication protocol/arrangement in the fuel dispenser pump


it is possible to provide modularity to the system along with security, long distance communication range and encryption of data to avoid tampering.
Thus there is a need to provide a fuel dispensing unit comprising secure communication arrangement for connecting various sensing units and main card of the fuel dispenser
The present inventors have found that an improved fuel dispenser unit can be achieved, comprising a processing unit having an automated communication protocol/arrangement providing long distance communication range with multi master functionality and data encryption to avoid tampering. It has been found that the disadvantages like tampering, limited distance communication range between the individual units and the main control unit of the dispensing unit and non modularity of the design of the unit can be avoided by the unique design of the fuel dispensing unit of the present invention.
OBJECTS OF THE INVENTION
Accordingly, one object of the present invention is to overcome the disadvantages of the prior art.
Another object of the present invention is to provide a fuel dispenser unit having processing unit connected to plural sensor means on a customized communication protocol.
It is yet another object of the present invention to provide a multi master-multi slave communication protocol.
SUMMARY OF THE INVENTION


Accordingly, one aspect of the present invention is to provide a fuel dispensing unit for providing secured communication between different sensing units and main card of the dispenser, said dispensing unit comprising :
sub-unit which includes
a processing unit for controlling fuel dispensing wherein said processing unit comprises an automated communication protocol/arrangement adapted to support a specific length of an identifier frame;
plural independent sensor unit in operative connection with said processing unit so as to receive and/or send signals from/to the processing unit
wherein said communication protocol/arrangement provides long distance communication range with multi master functionality and data encryption to avoid tampering.
The other objects and advantages of the present invention will be apparent from the description and the description provided hereinbelow with reference to the accompanying figures.
DESCRIPTION OF THE INVENTION
The fuel dispensing unit of the present invention comprises a sub unit which includes processing unit or main card and plural sensor means or slave cards. These independent cards are those of sensor for counting the dispenser pulses, relay card for switching on and off the motors of dispenser, keypad cum display card for human interface and combinations thereof. Each independent card has its own controller. The independent


cards communicate with the main card or the processing unit on a customized CAN protocol.
The CAN BUS facilitates modularity of the system as when a new concept has to be implemented, the CAN architecture provides an option of creating a new card and adding it on the CAN BUS.
The CAN BUS architecture as used in the present invention is CAN 2.0 B, with 29 bits identifier frame. The said 29 bits identifier frame is divided into the following parts:
1. Eight bit message ID: contains the message to be sent to different cards.
2. Three bit source device ID: containing the source device identification number for the generated CAN frame, Identification of device which is initiating the message.
3. Three bit source device type: containing the source type for the generated CAN frame.
4. Five bits for high DB ID: contains high database ID of the pump parameter
5. Three bits for low DB ID: contains low database ID of the pump parameter
6. Three bit destination device ID: contains the destination device identification number for the generated CAN frame, Identification of device which is receiving the message.
7. Three bit destination device type: containing the destination type for the generated CAN frame
8. One bit for read/ write: containing the CAN frame for read or write operation.
CAN is a multi master-multi slave protocol. It provides modularity to the system along with long distance communication and data encryption. Further to develop the system the identifier frame of the CAN protocol is customized so that the main card can send data as well as retrieve data

from the slave cards in secure manner. The slave cards are also capable of initiating communication with any of the cards.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
Figure 1 illustrates the architectural diagram of the fuel dispensing unit
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWING
Figure 1 shows the fuel dispensing unit comprising a processing unit or CCU main card in connection with various dispenser electronic units on a CAN BUS architecture. The various units are Electro Mechanical Totalizer (EMT), Human Machine Interface(HMI), Flow Quantizers, etc.. Flow quantizer cards for measuring the pulses, relay card for switching on and off the motors of dispenser, keypad cum display card for human interface. Signals from the sensor means are transmitted through CAN Bus architecture to the CCU main Card which controls the fuel dispensing rate. Flow quantizers (FQ1, FQ2, FQ3 and FQ4) are connected to the CAN bus.


WE CLAIM
1. A fuel dispensing unit for providing secured
communication between different sensing units and main
card of the dispenser, said dispensing unit comprising:
sub-unit which includes
a processing unit for controlling fuel dispensing wherein said processing unit comprises an automated communication protocol/arrangement adapted to support a specific length of an identifier frame;
plural independent sensor unit in operative connection with said processing unit so as to receive and/or send signals from/to the processing unit
wherein said communication protocol/arrangement provides long distance communication range with multi master functionality and data encryption to avoid tampering.
2. A fuel dispensing unit as claimed in claim 1, wherein the identifier frame comprises 29 bits.
3. A fuel dispensing unit as claimed in claims 1 and 2, wherein the identifier frame comprises selectively 8 bit message ID, 3 bit source device ID, 3 bit source device type, 5 bits for high DB ID: contains high database ID of the pump parameter, 3 bits low DB ID, 3 bit destination device ID, 3 bit destination device type, 1 bit read/write and combinations thereof.
4. A fuel dispensing unit as claimed in claims 1 to 3, wherein 8 bit message ID comprises different message for different cards.


5. A fuel dispensing unit as claimed in claims 1 to 3, wherein 3 bit source device ID comprises source ID for generated control area network (CAN) frame being identification number of device which is initiating the message.
6. A fuel dispensing unit as claimed in claims 1 to 3, wherein 3 bit destination device ID comprises destination ID for generated control area network (CAN) frame being identification number of device which is receiving the message.
7. A fuel dispensing unit as claimed in claim 1 wherein the plural independent sensor units comprises multiple cards connected to the processing unit.
8. A fuel dispensing unit as claimed in claim 7, wherein multiple cards are selectively sensor for counting pulses (flow quantizers), relay card for switching on and off motors of dispensing unit, keypad cum display card for human interface and combinations thereof.
9. A fuel dispensing unit as claimed in claim 1, wherein the automated communication protocol/arrangement is over a control area network (CAN) bus.
10. A fuel dispensing unit as claimed in claim 4, wherein CAN bus comprises multi master-multi slave architecture.




ABSTRACT
SECURE COMMUNICATION OVER CAN FOR FUEL DISPENSER
The present invention relates to a fuel dispensing unit for providing secured communication between different sensing units and main card of the dispenser. The dispensing unit comprises a processing unit having an automated communication protocol/arrangement adapted to support a specific length of an identifier frame, plural independent sensing units in operative connection with said processing unit so as to receive and/or send signals from/to the processing unit. The communication protocol/arrangement provides long distance communication range with multi master functionality and data encryption to avoid tampering.
Figure 1