Microchips and remote control devices comprising same

• US 5,517,187 A
• Filed: 02/18/1993
• Issued: 05/14/1996
• Est. Priority Date: 05/29/1990
• Status: Expired due to Term

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Nanoteq (Proprietary) Limited
• Inventors: Bruwer, Frederick J., Kuhn, Gideon J., Smit, Willem
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): Holloway, III, Edwin C.
• Application Number:
  US08/019,821
• Time in Patent Office: 1,181 Days
• Field of Search: 340/825.3, 340/825.31, 340/825.34, 340/825.2, 340/825.21, 340/825.56, 340/825.69, 340/825.72, 235/382.5, 307/10.2, 307/10.5, 361/172, 70/256, 380/23
• US Class Current: 340/5.26
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/4097 using mutual authentication between devices and transaction partners
• CPC Class Codes: G07C 2009/0023 with encription of the transmittted data signal
• CPC Class Codes: G07C 2009/00769 with data transmission performed by wireless means
• CPC Class Codes: G07C 2009/00928 for garage doors
• CPC Class Codes: G07C 2209/06 Involving synchronization or resynchronization between transmitter and receiver; reordering of codes
• CPC Class Codes: G07C 9/00182 operated with unidirectional data transmission between data carrier and locks
• CPC Class Codes: G07F 17/0014 for vending, access and use of specific services not covered anywhere else in G07F17/00 meter-controlled dispensing of liquid, gas or electricity G07F15/00
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: G07F 7/1016 Devices or methods for securing the PIN and other transaction-data, e.g. by encryption arrangements for secret communication, see H04L9/00

Abstract

Encoder and decoder microchips suitable for use in remote control devices, are disclosed. The encoder microchip comprises means for performing an encoding function on an identification number embedded in the said microchip and a combination of a unit number and a stepping counter value, so as to generate a transmission value which is only decodable by a related decoding function having access to the same identification number. The decoder microchip comprises means for decoding the transmission value into a decoded unit number and a decoded counter value and means for comparing the decoded counter value with a decoder counter value range. The encoder and decoder microchips are also provided with means for synchronizing the decoder microchip with a particular encoder microchip which has generated a synchronization command.

Claims

1. A system which includes an encoder microchip and a decoder microchip, wherein:

said encoder microchip comprises;

means for storing an identification number,

means for storing a counter value,

means for changing the value of said counter value each time the encoder microchip is operated, and

encoding means for performing a nonlinear encoding function on said counter value using said identification number, so as to generate a transmission value;

said decoder microchip comprises;

means for storing a second identification number,

means for receiving said transmission value from said encoder microchip,

means for performing a decoding function on said transmission value using said second identification number, so as to generate from said transmission value a decoded counter value,

means for storing a second decoded counter value obtained from the decoding of a transmission value of a previous transmission by said means for performing a decoding function; and

means for performing a format scan on signals so as to identify signals conforming to a specific format.

2. An encoder microchip comprising:

means for storing an identification number;

means for storing a counter value;

means for changing the value of said counter value only when the encoder microchip is operated; and

encoding means for performing an encoding function on at least said counter value using said identification number, so as to generate a transmission value.

3. An encoder microchip as claimed in claim 2, further comprising:

means for indicating a low power supply voltage condition.

4. An encoder microchip as claimed in claim 2, wherein said encoding means generates said transmission value decodable to provide said counter value.

5. A transmitter remote control device, comprising:

an encoder microchip as claimed in claim 2;

means for modulating the transmission value; and

means for transmitting the modulated transmission value to a matched receiver remote control device.

6. An encoder microchip as claimed in claim 2, further comprising:

means for forming a unit number selected from the group consisting of information representing a command, information representing an input value, information representing a transmitter number and a constant value;

wherein said encoding means performs an encoding function on said counter value and on the unit number using said identification number, so as to generate said transmission value.

7. An encoder microchip as claimed in claim 6, further comprising:

synchronization means for generating, when required, a synchronization counter value and a synchronization unit number;

means for combining said synchronization counter value and said synchronization unit number to produce a combined value, said combined value being encoded by said encoding means performing said encoding function thereon, using said identification number, so as to generate a synchronization transmission value.

8. An encoder microchip according to claim 6, comprising:

means for storing information selected from the group consisting of information representing a command, information representing a transmitter number and information representing a constant.

9. An encoder microchip as claimed in claim 6 wherein said unit number also contains information on a technology used in the encoder.

10. An encoder microchip as claimed in claim 6, wherein said encoding means generates said transmission value decodable to provide said counter value and said unit number.

11. A system which includes an encoder microchip according to claim 2 and a decoder microchip which comprises:

means for storing a second identification number;

means for receiving said transmission value from said encoder microchip;

means for performing a decoding function on said transmission value using said second identification number, so as to generate from said transmission value at least a decoded counter value; and

means for storing a second decoded counter value obtained from the decoding of a transmission value of a previous transmission by said means for performing a decoding function.

12. A system as claimed in claim 11, said decoder microchip comprising distinguisher means for distinguishing between a decoded unit number for normal operation, a decoded unit number for synchronization purposes, and a decoded unit number for other command purposes.

13. A system as claimed in claim 11 further including receiving means for receiving a transmission value from a matched transmitter remote device.

14. A system as claimed in claim 11, further comprising:

means for comparing the decoded counter value with the second decoded counter value stored in the means for storing a decoded counter value obtained from the decoding of a transmission value of the previous transmission, and for accepting or rejecting the transmission value as respectively valid or invalid according to whether or not the decoded counter value falls within a predetermined range of said second decoded counter value;

wherein said means for performing said encoding function performs said encoding function on said counter value and a unit number using said identification number, and said means for performing a decoding function generates from said transmission value said decoded counter value and a decoded unit number.

15. A system as claimed in claim 14, said decoder microchip comprising:

means for comparing the decoded counter value and the decoded unit number with a predetermined format and, upon a valid format having been received by the decoder microchip, for synchronizing the decoder counter value of the said decoder microchip with the counter value of the encoder microchip.

16. A system as claimed in claim 14, wherein said decoder microchip comprises means for providing at least one output indicative of information contained in an accepted decoded transmission value.

17. A system as recited in claim 14, wherein said means for comparing accepts or rejects said transmission value as respectively valid or invalid when said decoded counter value is within only a forward range of a previously decoded counter value.

18. A system as claimed in claim 14, wherein said decoder microchip comprises means for storing a plurality of counter values, each being related to a different encoder microchip.

19. A system as claimed in claim 18, wherein said decoder microchip comprises means for selecting a counter value from the plurality of counter values, based upon information derived from the decoded unit number.

20. A transmitter remote control device, comprising:

encoder means for performing an encoding function on an identification number embedded in the encoder means and a combination of a unit number and a variable counter value so as to generate a transmission value, said counter value depending on a number of times the encoding function is performed; and

a transmitter for modulating and transmitting said transmission value.

21. A transmitter remote control device as claimed in claim 20, wherein said unit number is derived from information selected from the group consisting of information representing a command, information representing an input value, information representing a transmitter number, a constant value, and information representing a technology used in the encoder.

22. An encoder microchip as claimed in claim 20, wherein said encoding means comprises a non-linear encoder.

23. A decoder microchip comprising:

first means for storing an identification number;

second means for storing at least a first counter value;

output means;

input means for data;

means for performing a decoding function on the received data using said identification number so as to generate a second counter value;

third means for comparing the second counter value with the first counter value;

activating means for activating, if a comparison carried out by said third means shows that the second counter value is within a defined range of the first counter value the output means; and

storage means for storing information relating to said second counter value in the second means if said output is activated.

24. A decoder microchip according to claim 23, comprising:

receiver means for receiving signals; and

means for performing a format scan on received signals so as to identify and act on values of valid format.

25. A system as recited in claim 23, wherein said means for activating activates said output means when said second counter value is within only a forward range of said first counter value.

26. A decoder microchip according to claim 23, wherein the output means, when activated, provides an indication of information contained in an accepted decoded transmission value.

27. A decoder microchip according to claim 23, wherein the output means provides an indication of at least one of predetermined different transmitter modes contained in an accepted decoded transmission value.

28. A decoder microchip according to claim 23, wherein the second storage means stores a plurality of counter values, each being related to a different encoder microchip.

29. A decoder microchip according to claim 28, comprising:

means for selecting a counter value from the plurality of counter values based upon information derived from the unit number.

30. A decoder microchip as claimed in claim 23, comprising:

activating means for activating, if a comparison carried out by said third means shows that the second counter value is within a defined range of the first counter value, the output means.

31. A decoder microchip as claimed in claim 30, comprising:

fourth means for storing reference information selected from the group consisting of information representing at least one command, and information representing a constant value;

wherein said means for performing a decoding function performs a decoding function on the received data using said identification number so as to generate said second counter value and a second unit number containing information selected from the group consisting of information representing a command, information representing an input value, information representing a transmitter number, a constant value, and information representing a technology type; and

fifth means for comparing at least part of the unit number with at least part of the reference information.

32. A decoder microchip according to claim 31, comprising:

means for distinguishing between different commands in said command information contained in the unit number.

33. A remote control system which comprises a transmitter and a receiver, the transmitter comprising:

first means for storing a first identification number;

second means for storing a counter value which is related to a number of times the transmitter is activated;

means for performing an encoding function on the first identification number and on the counter value so as to generate a transmission value; and

means for transmitting the transmission value to the receiver and indicating an activation of the transmitter to a user;

the receiver comprising;

third means for storing a second identification number which is the same as the first identification number;

means for receiving said transmission value; and

means for performing a decoding function, using the second identification number, on the received transmission value, so as to generate a decoded counter value.

34. A remote control system as claimed in claim 33, comprising:

fourth means for storing a unit number comprising information selected from a group consisting of information representing a command, information representing an input value, information representing a transmitter number, a constant value and information representing a technology used in the encoder;

wherein;

said means for performing an encoding function performs an encoding function on the first identification number and on a combination of the counter value and the unit number so as to generate said transmission value; and

said means for performing a decoding function performs a decoding function, using the second identification number, on the received transmission value, so as to generate at least said decoded counter value and a decoded unit number.

35. A remote control system which comprises a transmitter and a receiver, the transmitter comprising:

first means for storing a first identification number;

second means for storing an encoder counter value;

means for performing an encoding function on at least the first identification number and the encoder counter value so as to generate a transmission value, the encoder counter value being dependent on a number of times the encoding function is performed; and

means for transmitting the transmission value to the receiver and indicating an activation of the transmitter to a user;

the receiver including;

third means for storing a second identification number which is the same as the first identification number;

means for receiving said transmission value;

means for performing a decoding function, using the second identification number, on the received transmission value, so as to generate at least a decoded counter value that is the same as the encoder counter value;

fourth means for storing the decoded counter value;

means for comparing the decoded counter value to the decoder counter value which is stored in the fourth means and which was generated from a preceding received transmission value;

means for determining whether the decoded counter value falls within a particular range with regard to the decoded counter value; and

means for causing a value related to the decoded counter value to be stored in the fourth means if the comparison shows that the decoder counter value is within a said particular range.

36. A system as recited in claim 35, wherein said means for determining determines whether said decoded counter value if said decoded counter value is within only a forward range of said decoded counter value stored in said fourth means.

37. An encoder microchip, comprising:

means for storing an identification number,

means for storing a counter value,

means for forming a unit number selected from the group consisting of information representing a command, information representing an input value, information representing a transmitter number and a constant value,

means for changing the Value of said counter value each time the encoder microchip is operated, and

encoding means for performing an encoding function on said counter value and on said unit number using said identification number, so as to generate a transmission value;

wherein said unit number is modified related to a length of time that the encoder is operated.

38. An encoder microchip comprising:

a counter having a counter value;

a memory connected to said counter;

an encoder connected to said counter and said memory for incrementing said counter, for performing an encoding function on said counter value using an identification number stored in said memory and for generating a transmission value.

39. A decoder microchip comprising:

a memory having a stored counter value from a previous transmission;

a input data port;

a decoder, connected to said memory and said input data port, for performing a decoding function on data received by said input data port using an identification number stored in said memory and for generating a decoded counter value;

a comparator connected to said decoder and said memory;

an output circuit; and

an output activation circuit, connected to said comparator and said output circuit, for activating said output circuit, for comparing said decoded counter value to the stored counter value, and for storing said decoded counter value in said memory, if said decoded counter value is within a defined range of said stored counter value.

40. A decoder microchip as recited in claim 39, wherein said output activation circuit activates said output circuit when said decoded counter value is within only a forward range of said stored counter value.