Gaming machine having truly random results

• US 5,873,781 A
• Filed: 11/14/1996
• Issued: 02/23/1999
• Est. Priority Date: 11/14/1996
• Status: Expired due to Fees

• Current Assignee: Sg Gaming, Inc. (Scientific Games Corporation)
• Original Assignee: Bally Gaming International Incorporated (Scientific Games Corporation)
• Inventors: Keane, Martin A.
• Primary Examiner(s): Manuel, George
• Application Number:
  US08/749,292
• Time in Patent Office: 831 Days
• Field of Search: 463/20, 463/21, 463/22, 273/274, 364/717.01, 364/717.02, 364/717.06
• US Class Current: 463/22
• CPC Class Codes: G07C 15/006 electronically
• CPC Class Codes: G07F 17/32 for games, toys, sports, or amusements
• CPC Class Codes: G07F 17/3202 Hardware aspects of a gaming system, e.g. components, construction, architecture thereof

Abstract

A gaming machine produces truly random results using a noisy oscillator to randomly vary the frequency of a clock signal used to cycle a counter through its states. Multiple random numbers can be generated during the same game using the same circuitry, yet still achieve truly random results.

Claims

1. A gaming machine, comprising:

a circuit for generating a random game result, said circuit comprising means for generating truly random events and means for producing, in accordance with at least one prespecified probability distribution, independent game results based upon said truly random events; and

means for displaying the game result.

2. A gaming machine comprising:

a circuit for generating a random game result, said circuit comprising means for generating truly random events and means for producing, in accordance with at least one prespecified probability distribution, independent game results based upon said truly random events; and

means for displaying the game result;

wherein said generating means comprises a noise diode.

3. A gaming machine, comprising:

a circuit for generating a random value, said circuit having a clock input;

noisy oscillator means for generating a clock input signal having a random frequency to be provided to said clock input;

means for selecting a state of said circuit as the random value;

means for translating the random value into a game result; and

means for displaying the game result.

4. The gaming machine of claim 3 wherein said noisy oscillator means comprises a digital noise source.

5. The gaming machine of claim 4 wherein said noisy oscillator means comprises a shift register.

6. The gaming machine of claim 3 wherein said noisy oscillator means comprises means for generating noise from an independent physical process.

7. The gaming machine of claim 6 wherein said generating means comprises a noise diode.

8. The gaming machine of claim 7 wherein said generating means further comprises at least one op amp for amplifying noise generated by said noise diode.

9. A gaming machine, comprising:

a circuit for generating a random game result, at least a portion of said circuit forming a finite state machine wherein each state corresponds to a potential game result and wherein said circuit has a clock input;

noisy oscillator means for generating a clock input signal having a random frequency on a noisy oscillator output to be provided to said clock input, the clock input signal clocking the finite state machine through its states;

means for selecting a state of the finite state machine;

means for translating the selected state of the finite state machine into a game result; and

means for displaying the game result.

10. The gaming machine of claim 9 wherein said circuit generates at least two random game results per game.

11. The gaming machine of claim 9 wherein said circuit includes a counter.

12. The gaming machine of claim 9 wherein said circuit generates a random game result in accordance with a uniform probability distribution.

13. The gaming machine of claim 9 wherein said circuit generates a random game result in accordance with a nonuniform probability distribution.

14. A gaming machine requiring generation of at least two random numbers per game, comprising:

means for generating a random number within a first predetermined range of numbers, said generating means including a clock input and said generating means cycling through a plurality of states, each state corresponding to one of the numbers within the first predetermined range of numbers;

means for sequentially querying said generating means to select the existing state of said generating means as a random number;

noisy oscillator means for producing a signal having a random frequency within a second predetermined range of values, wherein said signal is input to said clock input;

means for translating the sequentially selected random numbers into at least one game outcome; and

means for displaying the at least one game outcome.

15. The gaming machine of claim 14 wherein said generating means includes a counter.

16. The gaming machine of claim 14 wherein the random numbers are uniformly distributed over the first predetermined range of numbers.

17. The gaming machine of claim 14 wherein the random numbers are nonuniformly distributed over the first predetermined range of numbers.

18. The gaming machine of claim 14 wherein each number in the first predetermined range of numbers corresponds to only a single state of said generating means.

19. A nonuniform probability distribution gaming machine having a number of possible game results, comprising:

means for generating a first random number uniformly distributed on a first predetermined range of numbers;

means for generating a second random number uniformly distributed on a second predetermined range of numbers;

a memory for storing a main array having an entry for each number in the first predetermined range of numbers and an alias array having an entry for each number in the first predetermined range of numbers wherein each main array entry is a number within the second predetermined range of numbers and wherein each alias array entry is a number in the first predetermined range of numbers;

a processor electronically connected to said memory, said means for generating a first random number and said means for generating a second random number, for determining a game result based upon said first random number, said second random number, said main array and said alias array; and

means for displaying the game result.

20. The gaming machine of claim 19 wherein said means for generating a first random number comprises a first counter.

21. The gaming machine of claim 20 wherein said means for generating a second random number comprises a second counter.

22. The gaming machine of claim 19 wherein the game result is the first random number when the second random number is less than or equal to the main array entry corresponding to the first random number and wherein the game result is the alias array entry corresponding to the first random number when the second random number is greater than the main array entry corresponding to the first random number.

23. The gaming machine of claim 19 wherein the gaming machine is a slot machine.

24. A nonuniform probability distribution gaming machine having at least two stages, each stage of which has a corresponding number of possible game results, comprising:

first means for generating a first random number uniformly distributed on a first predetermined range of numbers corresponding to the set of possible game results for each stage, said first generating means including a first clock input and said first generating means cycling through a plurality of states, each state corresponding to one of the numbers within the first predetermined range of numbers;

second means for generating a second random number uniformly distributed on a second predetermined range of numbers for each stage, said second generating means including a second clock input and said second generating means cycling through a plurality of states, each state corresponding to one of the numbers within the second predetermined range of numbers;

means for sequentially querying said first generating means to select the existing state of said first generating means as a first random number for each stage;

means for sequentially querying said second generating means to select the existing state of said second generating means as a second random number for each stage;

first noisy oscillator means for producing a first signal having a random frequency within a first predetermined range of values, wherein said first signal is input to said first clock input;

second noisy oscillator means for producing a second signal having a random frequency within a second predetermined range of values, wherein said second signal is input to said second clock input;

a memory for storing a main array and an alias array for each stage, each said main array having an entry for each possible game result for that stage and each said alias array having an entry for each possible game result for that stage, wherein each main array entry is a number within the second predetermined range of numbers for that stage and wherein each alias array entry is one of the possible game results for that stage;

a processor electronically connected to said memory, said first generating means and said second generating means, said processor determining a game result for each stage based upon said first random number, said second random number, said main array and said alias array for that stage; and

means for displaying the game results.

25. A gaming machine, comprising:

means for generating a random game result, said means comprising means for generating truly random events and means for producing, in accordance with at least one probability distribution, independent game results based upon said truly random events; and

means for displaying the game result.