Selective call receiver theft protection device

• US 5,073,767 A
• Filed: 12/05/1989
• Issued: 12/17/1991
• Est. Priority Date: 12/05/1989
• Status: Expired due to Term

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Lenhart, Brian P. Jr., Johnson, Rick, Holmes, Thomas F.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US07/446,368
• Time in Patent Office: 742 Days
• Field of Search: 340/311.1, 340/542, 340/543, 340/568, 340/571, 340/572, 340/825.22, 340/825.32, 340/825.5, 340/825.44, 340/825.31, 307/9.1, 307/10.3, 307/10.4, 307/10.5, 235/382.5
• US Class Current: 340/7.4
• CPC Class Codes: G08B 3/1066 with other provisions not elsewhere provided for, e.g. turn-off protection

Abstract

A selective call receiver allows reprogramming of the options stored within a code plug only after entry of a correct password. After a predetermined number of unsuccessful attempts to enter a correct password, the selective call receiver is user disabled such that the user may not reenable the selective call receiver without returning the receiver to the manufacturer or without replacing expensive components thereof.

Claims

1. An electronic device comprising:

programmable memory means for storing password information and a predetermined encryption algorithm;

interface means for transmitting information to and receiving data from an external programming device;

data conversion means for translating said data received according to said predetermined encryption algorithm to obtain password data and reprogramming data;

reprogramming means for reprogramming said programmable memory means with said reprogramming data if said password data is substantially equivalent to said password information; and

disabling means for user disabling said electronic device if said password data is not substantially equivalent to said password information on each of a predetermined number of inputs.

2. The electronic device of claim 1 further comprising counter means for initializing a lockout counter if said password data is substantially equivalent to said password information and for counting each input of said password data where said password data is not substantially equivalent to said password information, wherein said disabling means user disables said electronic device in response to said lockout counter counting to said predetermined number.

3. The electronic device of claim 1 wherein said electronic device comprises at least one output device and wherein said disabling means user disables said at least one output device if said password data is not substantially equivalent to said password information on each of said predetermined number of inputs.

4. The electronic device of claim 1 further comprising lockout means for user disabling said input means if said password data is not substantially equivalent to said password information on each of said predetermined number of inputs.

5. A selective call receiver comprising:

a reprogrammable memory;

an input/output interface for allowing communication between said reprogrammable memory and an external programming device; and

device disabling means for user disabling said selective call receiver in response to a predetermined number of unauthorized attempts by said external programming device to reprogram at least a portion of said reprogrammable memory.

6. The selective call receiver of claim 5 further comprising output means for presenting information to a user, and wherein said device disabling means comprises:

a lockout counter for counting each of said unauthorized attempts to reprogram said reprogrammable memory; and

output disabling means for user disabling said output means in response to said lockout counter counting to said predetermined number.

7. The selective call receiver of claim 5 wherein said device disabling means further comprises:

lockout means for preventing any further attempts to reprogram said reprogrammable memory in response to said predetermined number of unauthorized attempts to reprogram at least said portion of said reprogrammable memory.

8. The selective call receiver of claim 6 further comprising:

authorization means for generating a first signal if password data received from said external programming device via said input/output interface is substantially equivalent to password information stored within said reprogrammable memory and for generating a second signal if said password data is not substantially equivalent to said password information;

reprogramming means for reprogramming in response to said first signal at least a portion of said reprogrammable memory with reprogramming data received from said external programming device via said input/output interface; and

counter adjusting means for initializing said lockout counter for each occurrence of said first signal and for incrementing said lockout counter for each occurrence of said second signal.

9. The selective call receiver of claim 6 wherein said output means comprises a display device.

10. The selective call receiver of claim 6 wherein said output means comprises an audio alert device.

11. The selective call receiver of claim 6 further comprising interface disabling means for user disabling said input/output interface in response to said lockout counter counting to said predetermined number.

12. The selective call receiver of claim 9 wherein said display device comprises an alphanumeric display device.

13. The selective call receiver of claim 9 wherein said output means further comprises an audio alert device.

14. The selective call receiver of claim 10 wherein said output disabling means comprises alert means for activating said audio alert device in a predetermined manner.

15. The selective call receiver of claim 12 wherein said output disabling means comprises stored message display means for providing stored message information to said display device for presentation thereon.

16. The selective call receiver of claim 13 wherein said output disabling means comprises continuous alert means for continuously activating said audio alert device in response to said lockout counter counting to said predetermined number.

17. The selective call receiver of claim 13 wherein said output disabling means comprises intermittent alert means for intermittently activating said audio alert device in response to said lockout counter counting to said predetermined number.

18. The selective call receiver of claim 14 wherein said alert means intermittently activates said audio alert device.

19. The selective call receiver of claim 14 wherein said alert means continuously activates said audio alert device.

20. The selective call receiver of claim 15 wherein said stored message display means provides said stored message information to said display device for continuously presenting thereon.

21. The selective call receiver of claim 15 wherein said stored message display means provides said stored message information to said display device for intermittently presenting thereon.

22. The selective call receiver of claim 15 wherein said stored message display means provides said stored message information to said display device for presentation thereon upon each activation of said display device.

23. The selective call receiver of claim 8 further comprising data conversion means for de-encrypting a password received from said external programming device according to a predetermined algorithm stored within said reprogrammable memory to obtain said password data for providing to said authorization means.

24. The selective call receiver of claim 23 wherein said data conversion means de-encrypts data received from said external programming device according to said predetermined algorithm to obtain said reprogramming data for providing to said reprogramming means.

25. In an electronic device having a reprogrammable memory, an input/output port for communication with an external device, and at least one output device, said at least one output device capable of being user disabled such that a user of the electronic device may not reenable the at least one output device, a method for reprogramming the reprogrammable memory comprising the steps of:

(a) establishing communications via the input/output port with an external programming device;

(b) receiving a password from the external programming device;

(c) determining whether said password received from the external programming device is equivalent to a predetermined password stored in said reprogrammable memory;

(d) repeating steps (b) and (c) if said password received is not equivalent to the predetermined password and if a predetermined number of said passwords have not been received, said predetermined number greater than one;

(e) user disabling said at least one output device after said predetermined number of said passwords so received are determined to be not equivalent to the predetermined password;

(f) receiving reprogramming information from said external programming device if said password is equivalent to the predetermined password; and

(g) reprogramming said reprogrammable memory in response to said reprogramming information.

26. The method according to claim 25 wherein said at least one output device comprises a display and a control means for activating said display, and said step (e) of user disabling said at least one output device of said electronic device includes the step of displaying a predetermined message in response to all subsequent activations of said display by said control means.

27. The method according to claim 25 wherein said at least one output device comprises an audible alert, and said step (e) of user disabling said at least one output device includes the step of activating said audible alert in a predetermined manner in response to said predetermined number of said passwords so received not equivalent to said predetermined password.

28. The method according to claim 25 further comprising the step of

(h) preventing further reception of said reprogramming information after said predetermined number of said passwords are received without receiving said predetermined password.

29. The method according to claim 25 wherein said step (b) of receiving said password comprises the steps of:

(i) receiving an encrypted password from said external programming device; and

(j) converting said encrypted password to said password according to a predetermined de-encrypting algorithm stored in said reprogrammable memory.