GAME CARDS

FIELD OF INVENTION The invention relates generally to electronic gaming systems. More specifically, the present invention relates to a method and apparatus for generating electronic game cards.

BACKGROUND OF THE INVENTION

Traditionally, bingo games are played in person where players pay a fee to participate. For a single bingo game, each player purchases one or more bingo game cards where each bingo game card is comprised of five columns (labeled with the letters "B", "I," "N," "G," and "O") and five rows of numbers. There are 75 possible bingo numbers: Bl-B15, 116-130, N31-N45, G46-G60, and O61-O75. Each of these numbers is represented by a ball in a rotating bin where balls are randomly selected. The number of a selected ball is announced to the players and the players mark their game cards accordingly if the announced number appears on their game card. The first player to have five marks in a line (along a row, column, or diagonal direction) wins that particular bingo game. Each bingo game proceeds until someone wins.

For each bingo game, each game card must be unique (i.e., the arrangements of numbers on each game card must be unique) so that there are no duplicate game cards. Thus, there is a need for a quick and efficient method of generating game cards for a bingo game in a seemingly random or pseudo-random manner where each game card contains a unique number arrangement. SUMMARY OF THE INVENTION The invention is directed towards a method and apparatus for generating a series of game cards where each game card has a unique arrangement of numbers. The arrangement of numbers of each game card is comprised of columns of number patterns. At the start of the method, several number patterns that are possible for one column of the game card are determined. These number patterns compose a set of number patterns that are possible for the column. Also, each number pattern in the set is associated with and identified by a numeral identifier. A game card having a unique arrangement of numbers can then be generated using the set of number patterns and a received serial number. This is achieved by first receiving the serial number and applying an algorithm to the serial number to produce an output value. Portions of the output value are then used to identify number patterns in the set of number patterns (determined initially) by using the numeral identifiers associated with the number patterns. An identified number pattern comprises one column of the game card. In some embodiments, the number values of one or more identified number patterns are shifted in accordance with the allowed values for a particular column of the game card. The identified or shifted number patterns are then grouped to form an arrangement of numbers that composes a single game card. BRIEF DESCRIPTION OF THE DRAWINGS The novel features of the invention are set forth in the appended claims. However, for purpose of explanation, several embodiments of the invention are set forth in the following figures. Figure 1 illustrates an example of a possible number pattern of a bingo game card. Figure 2 illustrates an example of unique number patterns possible for the "B" column of the game card. Figure 3 illustrates a gaming environment in which the invention is practiced according to one embodiment. Figure 4 illustrates one embodiment of the portable gaming machine. Figure 5 is a conceptual diagram of processes of the present invention used to produce game cards. Figure 6 illustrates a method for generating a series of unique game cards. DETAILED DESCRIPTION OF THE INVENTION The disclosure of Patent Application No. 10/391,934, filed March 19, 2003, entitled "Methods and Apparatus for a Portable Gaming Machine," is hereby expressly incorporated herein by reference. In the following description, numerous details are set forth for purpose of explanation. However, one of ordinary skill in the art will realize that the invention may be practiced without the use of these specific details. In other instances, well-known structures and devices are shown in block diagram form in order not to obscure the description of the invention with unnecessary detail. Methods of the present invention produce output values, number patterns, and game cards in a seemingly random or pseudo-random manner. As used herein, seemingly random or pseudo-random output values, number patterns, or game cards refer to output values, number patterns, or game cards that have substantially different values, number patterns, or arrangement of numbers so that they appear random or pseudo-random in relation to each other. The invention is directed towards a method and apparatus for generating a series of unique game cards where each game card contains one or more columns of number patterns. Initially, to generate a series of unique game cards, a set of unique number patterns that are possible for a first column of the game card are determined where each unique number pattern is identified by a numeral identifier. A serial number is then received by an algorithm that produces an output value. The output value is then partitioned into sub-sections where each sub-section identifies a number pattern in the set of number patterns for a particular column of the game card. A number pattern is identified for each column of the game card. In some embodiments, the number values of one or more identified number patterns are shifted in accordance with the allowed values for a particular column of the game card. The identified or shifted number patterns are then grouped to form a collective of number patterns (i.e., an arrangement of numbers) that composes a single game card. A next serial number is then received by the algorithm. In some embodiments, the next serial number is sequential to the serial number received by the algorithm just prior. In some embodiments, when the algorithm receives a set of non-random input values (serial numbers), it produces a set of output values that are seemingly random or pseudo-random in relation to one another. In some embodiments, when the algorithm receives two sequential numbers (n and n+1), it produces two output values that are seemingly random or pseudo¬ random in relation to one another. As such, the output value identifies number patterns in the set of number patterns in a seemingly random or pseudo-random manner. Thus, in accordance with the present invention, non-random input values (e.g., sequential serial numbers) produce seemingly random or pseudo-random game cards. In addition, the use of sequential serial numbers allows for easy record keeping of game cards to ensure that duplicate game cards are not produced for the same game. Several embodiments are described below in reference to a bingo game and bingo game cards having five columns and five rows of numbers. One of ordinary skill in the art, however, will realize that the processes of the invention can relate to other games and other games cards having different arrangements and/or characters (e.g., letters or other symbols). Bingo games can be played using electronic gaming machines. These gaming machines are loaded and made ready for play by electronically transferring data representing a bingo game from a sales terminal to the electronic gaming machine. For each bingo game, there is a set of game cards that are electronically daubed when a player entered number matches a number on a bingo game card. Each game card in a set of game cards for a single bingo game must be unique (i.e., the arrangements of numbers on each game card must be unique) and can be one of approximately 10 to the 26th power of possible unique number arrangements. Thus, there is a need for a quick and efficient method of generating a set of game cards in a seemingly random or pseudo-random manner where each game card contains a unique number arrangement so that there are no duplicate game cards for the same game. Figure 1 illustrates an example of a possible number pattern of a bingo game card 100. As shown in Figure 1, a bingo game card 100 is a number arrangement having 5 rows and 5 columns of numbers. The first, second, third, fourth, and fifth columns are labeled with the letters "B", "I," "N," "G," and "O," respectively. Each space in the "B" column contains a range of permitted number values from 1 - 15, each space in the "I" column contains a range of permitted number values from 16 - 30, each space in the "N" column (except for the center "free" space) contains a range of permitted number values from 31 - 45, each space in the "G" column contains a range of permitted number values from 46 - 60, and each space in the "O" column contains a range of permitted number values from 61 - 75. Also, a particular number can appear only once on a single game card. Note that number values in a particular column can be used in another column if the number values are shifted according to the permitted values for the other column. For example, the number values of the "B" column can be used in the "I" column if 15 is added to each number value of the "B" column. Similarly, the number values of the "B" column can be used in the "N," "G," and "O," columns if 30, 45, and 60, respectively, is added to each number value of the "B" column. Also note that for each column (except for the "N" column which contains the "free" space) there are 360,360 (15x14x13x12x11) possible number patterns. This is due to the fact that each column (except for the "N" column) contains five spaces that each can contain one of fifteen possible values with no duplicate values. Figure 2 illustrates an example of unique number patterns 205 possible for the "B" column of the game card. As shown in Figure 2, each unique number pattern 205 for the "B" column can be identified by a numeral identifier 210 (e.g., 214, 215, 216, etc.). In some embodiments, a set of unique number patterns for the "B" column are determined and stored to a computing device (such as a portable gaming machine) where each number pattern in the set of number patterns is identified by a numeral identifier. In the example shown in Figure 2, the number values in the number patterns 205 and numeral identifiers 210 progress in a systematic manner (i.e., the number patterns 205 and numeral identifiers 210 are not randomly associated). In other embodiments, however, the number patterns 205 and numeral identifiers 210 determined for the "B" column are randomly associated. Figure 3 illustrates a gaming environment 300 in which the invention is practiced according to one embodiment. The gaming environment 300 includes a sales terminal 310 and several portable gaming machines 315-350. Each portable gaming machine 315-350 is a self contained portable computer unit in size and shape resembling a laptop computer. The portable gaming machine 315-350 is battery powered and may be recharged by electrically coupling to a recharging rack 355. The portable gaming machine 315-350 also includes a motherboard that may include a smart media memory device. The sales terminal 310 activates the portable gaming machines 315-350 and makes them ready for playing bingo games. The activation process includes activating a selected number of game cards associated with a bingo game. The selected number of game cards for a bingo game depends upon the transactions between the bingo player and the sales terminal operator. For example, a bingo player desiring 10 game cards for a particular bingo game would compensate the sales terminal operator for the 10 game cards. The sales terminal operator in return would activate 10 game cards for the portable gaming machine 315-350. Activation may include electrically coupling the sales terminal 310 to the portable gaming machine 315-350 and transmitting an activation signal. Electrical coupling may be through physical devices, such as connectors and cables, or through infrared means, such as RS 232 or a smart card port. In some embodiments, each portable gaming machine 315-350 stores a set of unique number patterns possible for a first column ("B" column) of the game card (so that the number values in the number patterns range from 1 through 15). In some embodiments, each portable gaming machine 315-350 stores up to 8,192 unique number patterns for the first column of the game card. During the activation process, a serial number is also transmitted from the sales terminal 310 to the portable gaming machine 315-350 for each game card desired by the bingo player. The portable gaming machine 315-350 then performs an algorithm (discussed below) on the received serial number (input value) to produce an output value. The output value is then partitioned into five sub-sections where each sub-section identifies a particular number pattern in the set of unique number patterns possible for the first column. For example, a first sub-section of the output value may be used to identify a number pattern in the stored set of possible number patterns that is to be used as the number pattern for the first column of the game card. Similarly, a second, third, fourth, and fifth sub-section of the output value, respectively, may be used to identify a number pattern in the stored set of possible number patterns for the second, third, fourth, and fifth columns, respectively, of the game card. The number values of a number pattern identified for a second, third, fourth, or fifth column are then shifted by a predetermined offset value according to the permitted values for that particular column. As such, an offset value of 15 is added to each number value in the number pattern identified for the second column. Similarly, an offset value of 30, 45, and 60 is added to each number value in the number pattern identified for the third, fourth, and fifth columns, respectively. Figure 4 illustrates one embodiment of the portable gaming machine 400. The portable gaming machine 400 includes a bus 410, user interface 420, a processor 430, a non¬ volatile memory 440, a random access memory (RAM) 450, input terminal 460, a display 470, and a program memory 475. Bus 410 is a standard system bus for communicating information and signals. It allows communication between all devices 420-475 of the portable gaming machine 280. The user interface 420 may include a keyboard (not shown) that allows a bingo player to enter commands. Alternatively, the bingo player may also use the display 470 as a touch screen for entering commands. When the portable gaming machine 400 is coupled to a sales terminal 310, the input terminal 460 receives an activation signal and one or more serial numbers from the sales terminal 310. The non-volatile memory 440 is a permanent memory that stores information or instructions that are used by the processor 430. In some embodiments, the non-volatile memory 440 contains a set of number patterns that are possible for a first column ("B" column) of a game card where each number pattern in the set of number patterns is identified by a numeral identifier. The non-volatile memory 440 may also store software instructions that can be executed by the processor 430 to perform methods of the present invention. Alternatively, the program memory 475 stores code or instructions that can be executed by the processor 430 to perform methods of the present invention. Such instructions may perform an algorithm (such as an encryption algorithm) that receives an input value (serial number) having a first maximum value and produces an output value having a second maximum value, the second maximum value being larger than the first maximum value. For example, the algorithm may receive a five digit decimal number (having a maximum value of 99,999) as the input value and produce a 64 bit binary number (having a maximum value of 18,446,744,073,709,551,616) as the output value. In some embodiments, when the algorithm receives a set of non-random input values, it produces a set of output values that are seemingly random or pseudo-random in relation to one another. In some embodiments, if two sequential input values are received, the algorithm produces two output values having substantially different values. In some embodiments, at least 1A or 1A of the digits of the two output values are different. The algorithm may comprise, for example, the Data Encryption Standard (DES) algorithm or other encryption algorithm. The program memory 475 also stores instructions that configure the processor 430 to perform other methods of the present invention, such as receiving the output value produced by the algorithm, partitioning the output value into sub-sections, and identifying stored number patterns based on the sub-sections to produce a game card. The game cards associated with each game are then displayed on the display 470. Only the game cards that have been activated by the sales terminal 110 are retrieved by the processor 430 and provided for bingo player selection. Figure 5 is a conceptual diagram of processes of the present invention used to produce game cards. As shown in Figure 5, an input value 500 is received by an algorithm 505 to produce an output value 510. The algorithm 500 may be an encryption algorithm (such as the DES algorithm) or another algorithm type. In some embodiments, the input value 505 is a five digit decimal number and the output value 510 is a 64 bit binary number. The output value 510 is sub-divided into two or more sub-sections. In some embodiments, the 64 bit output value 510 is sub-divided into first 515, second 520, third 525, fourth 530, and fifth 535 sub-sections each having 13 bits. Note that two sub-sections must share at least one bit for each sub-section to have 13 bits. In the example shown in Figure 5, the second 520 and third 525 sub-sections share 1 bit although, in other embodiments, other sub-sections share one or more bits. Each sub-section of the output value 510 identifies a particular number pattern 540 in a set of number patterns to comprise a particular column of the game card. For example, the second sub-section 520 of the output value may be used to identify a particular number pattern 540 in a set of number patterns that is to comprise the second column of the game card. The set of number patterns (stored, for example, in the non- volatile memory 440) are number patterns possible for a particular column of the game card where each number pattern in the set is identified by an associated numeral identifier. A number pattern in the set of number patterns is identified by a sub-section of the output value by matching the value of the sub-section to the value of the numeral identifier associated with the number pattern. In some embodiments, the set of number patterns is a set of number patterns possible for a first column ("B" column) of the game card so that the number values in the number patterns range from 1 through 15. If each sub-section of the output value is comprised of 13 binary bits, each sub¬ section can identify one of 8,192 (2 λ 13) possible number patterns in a set of number patterns. Thus, only a maximum of 8,192 number patterns would need to be determined to produce the set of number patterns. In some embodiments, a maximum of 8,192 number patterns for a particular column of the game card are stored to a portable gaming machine. This greatly reduces the amount of storage space needed by the portable gaming machine since only a maximum of 8,192 number patterns for a single column of the game card is stored rather than 40,960 (5 x 8,192) number patterns for five columns of the game card. Number values of one or more identified number patterns are then shifted to produce one or more shifted number patterns 545. In some embodiments, the method adjusts the number values of the numbers pattern identified for the second, third, fourth, and fifth columns by adding an offset value according to the permitted values for each column. In some embodiments, an offset value of 15, 30, 45, and 60 is added to all number values in the number patterns identified for the second, third, fourth, and fifth columns, respectively. This produces shifted number patterns 545 for the second, third, fourth, and fifth columns. The identified or shifted number patterns for each column are then grouped into a collective of number patterns (i.e., an arrangement of numbers) that composes a single game card 550. In addition, to produce a bingo game card, the center number value in the third column is then changed to a "free" value (as shown in Figure 1). Figure 6 illustrates a method 600 for generating a series of unique game cards where each game card contains five columns of number patterns. The method 600 begins by determining (at 605) a set of unique number patterns that are possible for the first column of the game card where each unique number pattern is identified by a numeral identifier (as shown, for example, in Figure 2). The numeral identifiers associated with the set of number patterns compose a set of numeral identifiers. The number patterns and numeral identifiers may be randomly associated or not randomly associated. In some embodiments, the set of number patterns and the associated set of numeral identifiers are stored to a computing device (such as a portable gaming machine). The method 600 then receives (at 610) a serial number having value n. In some embodiments, the serial number is a five digit decimal number. The method 600 applies (at 615) an algorithm to the received serial number (input value) to produce an output value. In some embodiments, the algorithm is such that when a set of non-random input values are received, the algorithm produces a set of output values where the output values are seemingly random or pseudo-random in relation to one another. In some embodiments, the algorithm is an encryption algorithm and the output value is a 64 bit binary number. The method then partitions (at 620) the output value into five sub-sections. In some embodiments, each sub-section contains 13 bits where two sub-sections share one bit (as shown in Figure 5). Using the five sub-sections, the method identifies (at 625) a number pattern in the set of number patterns (determined at 605) for each column of the game card. For example, a first sub-section of the output value may be used to identify a particular number pattern for the first column of the game card. Similarly, a second, third, fourth, and fifth sub-section of the output value, respectively, may be used to identify a number pattern in the stored set of possible number patterns for the second, third, fourth, and fifth columns, respectively, of the game card. A number pattern in the set of number patterns is identified by a sub-section of the output value by matching the value of the sub-section to the value of the numeral identifier associated with the number pattern. The method then adjusts (at 630) number values of one or more identified number patterns to produce one or more shifted number patterns. In some embodiments, the method adjusts the number values of the number patterns identified for the second, third, fourth, and fifth columns by adding an offset value according to the permitted values for each column. In some embodiments, an offset value of 15, 30, 45, and 60 is added to all number values in the number patterns identified for the second, third, fourth, and fifth columns, respectively. This produces shifted number patterns that comprise the second, third, fourth, and fifth columns of the game card. The method then groups (at 635) the identified or shifted number patterns to form a collective of number patterns (i.e., an arrangement of numbers) that composes a single game card. In some embodiments, the identified number pattern for the first column and the shifted number patterns for the second, third, fourth, and fifth columns are combined to form an arrangement of numbers that composes a single bingo game card. Note that for producing a bingo game card, the center number value in the third column is then changed to a "free" value (as shown in Figure 1). The method then continues at step 610 where another serial number is received. In some embodiments, the next serial number received is sequential to the serial number received just prior (i.e., the next serial number has a value n+1). The method 600 then applies (at 615) the algorithm to the received serial number (input value) to produce an output value. In some embodiments, the algorithm is such that when two sequential input value (e.g., n and n+1) are received, the algorithm produces two output values that are seemingly random or pseudo-random in relation to one another. In some embodiments, if two sequential input values are received, the algorithm produces two output values where at least 1A or Vi of the digits of the two output values are different. The method then partitions (at 620) the output value into sub-sections, each sub-section identifying a number pattern in the set of number patterns (determined at 605) for a particular column of the game card. Note that the method can use non-random input values (e.g., sequential serial numbers) to produce seemingly random or pseudo-random output values that are used to identify number patterns in the set of number patterns. As such, non-random input values can be used to identify number patterns in the set of number patterns in a seemingly random or pseudo-random manner. Thus, non-random input values (e.g., sequential serial numbers) are used to produce game cards (created by grouping the number patterns into a collective, at step 635) in a seemingly random or pseudo-random manner. For example, a game card produced by a serial number of n will appear randomly or pseudo-randomly related to a game card produced by a serial number of n + 1. The use of sequential serial numbers allows for easy record keeping of game cards that have already been produced to ensure that duplicate game cards are not produced for the same bingo game. Also, sequential serial numbers are easy to determine and assign at the point of sale when the sales terminal activates a portable gaming machine to make them ready for playing bingo games. Several embodiments have been described above in reference to a bingo game and bingo game cards having five columns and five rows of numbers. One of ordinary skill in the art, however, will realize that the processes of the invention can relate to other games and other games cards having different arrangements and/or characters (e.g., letters or other symbols). While the invention has been described with reference to numerous specific details, one of ordinary skill in the art will recognize that the invention can be embodied in other specific forms without departing from the spirit of the invention. Thus, one of ordinary skill in the art would understand that the invention is not to be limited by the foregoing illustrative details, but rather is to be defined by the appended claims.