Controlled Access Systems

Abstract

A security system for use either as a means for establishing credit or for limiting access to restricted areas. The system operates with a card having a variable 20 by 20 row and column matrix as its internal configuration. The system may be programmed to read any number of digits in the matrix, in any combination and in any sequence. This feature allows the owner of the system to create unique card codes and to change these codes at any time. Programming is accomplished simply by closing a key switch and positioning the proper sequence of numbers on an input keyboard. The authorized holder of an identification card is assigned a unique keyboard number for his card depending on the owner's program. Each cardholder must then use his input number which is based on his card's internal configuration. In addition, further programming of this system provides eight levels of control. This feature allows a single installation to have up to eight increasing levels of security with no change in the card's unique configuration. Cards may be coded for entry to one area only, to all eight areas or to any intermediate number of areas. Similarly, credit ranges can be established in the same manner. Provision is also made to selectively lock out individual cardholders.

Description

BACKGROUND OF THE INVENTION

Due to the advent of a cashless society and increased necessity for security controls, plastic and metallic numbered cards are being used ever increasingly for purposes of identification. It is also an actively changing field of art in that owners of card systems are attempting to use more and more sophisticated type apparatus to prevent fraud or unauthorized entry while others, either through contests or for illegal purposes, are increasingly more active in attempts to break the codes or systems used on credit cards and the like.

Initially cards used only embossed numbers on the surface of the card which were mechanically reproduced on a document or were read with mechanical linkages. It is believed that the art then moved to magnetically sensitive strips of tape which, although they cannot be readily duplicated with the naked eye, were read and reproduced with suitable electronic equipment. Other efforts in the field have used apertures in the card or apertures hidden in the card, again sensitive and susceptible to reproduction with the use of X-ray or other suitable equipment. Most recent advances have combined numbers on the card with code numbers memorized by the user, said user numbers being directly related to the number on the card, related to a random combination of the numbers on the card or variably related to a random combination of the numbers on the card depending on a key number which repositions the digits in different combinations.

In these systems, however, each card uses one fixed card number and the card number is a limiting factor for security. For example, with a six digit number and a three digit secret number there are only eighteen three number groupings with six arrangements of each three number grouping or a total or maximum of 108 possibilities which may be utilized for each card number.

SUMMARY OF THE INVENTION

The invention disclosed herein represents the very latest in electronic security control. It has been designed to eliminate the shortcomings of existing systems, and provide maximum security at minimum cost. All components and circuitry are contained in the single wall mounted control unit, with a sturdy, tamper-proof chassis.

Access or credit is restricted to those persons with a properly encoded identification card and knowledge of a unique keyboard number for their card. Identification cards may be laminated plastic with an internal encoding pattern which is not vulnerable to heat, chemicals or electromagnetic force.

The invention is available with eight levels of control. This feature allows a single installation to have up to eight increasing levels of security with no change in the card's unique configuration. Cards may be coded for entry to one area only, to all eight areas, or to any intermediate number of areas. Should a user attempt to enter a secure area beyond his authorized level, a remote alarm is sounded, and the card is retained. Similarly, credit ranges can be established in the same manner.

The invention may be programmmed by the system owner to read any number of digits of a multiple row and column matrix, in any combination and in any sequence. This feature allows the owner to create unique codes for the users and to change these codes at any time. Programming is accomplished simply by closing a key switch and pushing a sequence of numbers on the input keyboard.

Each cardholder is then assigned and must use an input number which is based on his card's internal configuration. it is not possible to decipher the number by opening a card since the user never knows what all the digits are, which digits are being read, nor the order of reading. The encoding technique allows for a total of several thousand possible number combinations per card.

Provision is also made to selectively lock out individual cardholders. This feature provides a convenient means to locate and retain stolen credit cards or to deny access to discharged employees still holding a valid identification card. The employee's number is entered by the system owner into a location in the memory bank. This memory bank is scanned each timme a card is inserted. When a number entered by an unauthorized user of the system matches a number in memory, the card is retained, and a remote alarm is activated. Unauthorized members are entered into memory by a simple key-in procedure similar to the programming method. Turning the proper key enables the credit manager or personnel director or other authorized operator to enter the unauthorized number using the same input keyboard. That number remains in memory until it is removed or replaced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exemplary matrix showing a possible internal configuration of an identification card;

FIG. 2 is a simplified flow diagram of the operational steps of the invention; and

FIG. 3 consisting of FIGS. 3a - 3d, is a schematic diagram showing the logical techniques which are utilized to accomplish the purposes of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As explained in more detail below, operation of the invention is accomplished with three codes. The three codes utilized are: (1) a column code; (2) a row code; and (3) a user's code number.

As sketched in FIG. 1 a 20 by 20 matrix is provided which is read by the system to create a distinct number to be associated with a card. One embodiment which may be utilized employs an opaque insert implanted in the card which is cut or slotted to provide translucent areas which may be read with infrared readers. It should be understood that there is no limit in the size of the matrix, its extent being a choice of design. The infrared reader registers either the opaque or translucent portions of the interior of the card which can be converted into an on or off representation to be read in binary.

Which vertical rows on the card are to be read can be randomly selected and locked in with either a keyboard or by internal wiring (e.g., vertical rows 4, 5, 1 and 2). This is referred to as the "column program."

The horizontal rows are also selected by the system owner in any order or in any sequence on the keyboard and locked in (e.g., 2, 5, 7 and 3). Thereafter a programmed number must be punched in by the cardholder in the order selected before the machine will operate to accept the card.

In other words, suppose the column code is as indicated above, 4, 5, 1 and 2, and the system owner selects a row code of 2, 5, 7 and 3. Also assume that the binary representation cut into the interior of the card is as shown in FIG. 1. Each card utilized will be coded differently, thus providing distinct information. However, since each card will be coded for the entire matrix the information contained on the card will be nondiscrete without the use of the system. A user or cardholder would have to enter the number 2, 1, 1, 5 before the system would accept him as the cardholder. A sketch of the matrix as shown in FIG. 1 shows why.

The cardholder's program number is obtained as follows:

Row 2, Column 4 has a 0 Column 5 has a 0 Column 1 has a 1 Column 2 has a 0

Binary No. 0010 is decimal 2

Row 5, Column 4 has a 0 Column 5 has a 0 Column 1 has a 0 Column 2 has a 1

Binary No. 0001 is a decimal 1

Row 7, Column 4 has a 0 Column 5 has a 0 Column 1 has a 0 Column 2 has a 1

Binary No. 0001 is decimal 1

Row 3, Column 4 has a 0 Column 5 has a 1 Column 1 has a 0 Column 2 has a 1

Binary No. 0101 is decimal 5

Thus, the cardholder's number is 2115.

A variation can be made in either the column code or the row code, or the cardholder's code number or any combination thereof. Also, if the card is lost or stolen, it can't be used since whoever has it will not know the programmed number.

While an infrared reader is currently utilized to read an insert impregnated in a plastic card it should be obvious that the same type matrix can be impressed on a magnetic tape strip.

FIG. 2 is a simplified flow diagram of the operational steps of the invention. As the user approaches the control unit, an insert card light 13 is energized indicating the unit is in the ready condition. When a card is inserted properly at 14, the insert card light 13 is deenergized and the key code number lamp 15 is energized. Improper card insertion results in card rejection. As the card is being inserted optical readers 16 determine whether or not the card has been fully inserted and whether or not a specified number of digits have been read, for example, seven digits. In addition, logical programming 17 determines from other information obtained from the card a security or credit level to determine whether the cardholder is in the correct area.

If less than seven numbers were read, a card solenoid 18 is energized to enable the cardholder to remove the card 19 for reinsertion. If the cardholder is not in an authorized security area the card is rejected 20 and the reject lamp 21 is energized.

If the card has been properly utilized the cardholder may now insert data on an input keyboard 22. Logical gating and a comparator 23 initially match the cardholder's memorized key number with a programmed, unfixed and random number read from the card and then compares the number with unauthorized numbers in a random access memory 24. If the cardholders's memorized number and the programmed card number do not match or if the cardholder's key number is unauthorized, the card is rejected at 20 and the reject lamp 21 is energized.

It the cardholder enters the proper code and the code is not retained as an unauthorized code in the memory 24, all inputs to master AND gate 26 are enabled, the door 27 releases, the accept indicator 28 is energized and the card is ejected by the card solenoid 18. In the event an improper code is entered, the cardholder has two additional chances to key in the proper number. Should he fail, this is noted by a counter 25, the card is retained and a remote alarm is sounded. At this point, the card can only be removed by a security guard or other authorized persons holding a key to release the card with key switch 29.

The above operations are accomplished electronically in the following manner. As shown in FIG. 3, the system is programmed to read from a 20 by 20 matrix impregnated in a card, seven digits in four bit binary and one three bit digit for the security code. The column program 31 is shown as internally wired. It should be understood, however, that the column program 31 may be constructed in the same manner as the row code program described below and that variations can be made in the matrix configuration or the number of digits read and still be within the intention and scope of the invention as claimed.

Referring to the schematic diagram shown in FIG. 3, information in the interior of the card is read with the utilization of light sensitive transistors 43 through 51. On each of seven passes these transistors 43 through 49 are capable of detecting four binary bits which represent a decimal number plus three binary bits which represent a security code. In addition, transistors 50 and 51 detect insertion of the card and the bottom of the card.

When the card is inserted, top optical reader 50 is activated. The signal is amplified with amplifier 53 and is utilized to enable the card storage memory 54, the lock out memory 56, the keyboard storage memory 58, the third time counting circuit 60, to partially enable the door relay gate 26 and to serve as a master clear for other circuits as explained more fully below.

The card storage memory 54 is enabled through amplifier 53, lines 66, 67 and 68, which is the initial high signal on AND gate 72.. As explained below, as each additional four bit number is read the second input signal to AND gate 72 goes high activating the one shot 74 to load the data into the card storage memory 54.

The keyboard storage memory 58 is enabled through amplifier 53, lines 66, 76 through inverter 77 and OR gate 78, the output of which is fed by line 82 to counter 83. The normally low signal from amplifier 53 clears the counter 83. When the signal goes high it is inverted with inverter 77, disabling the OR gate 78 and this enabling the counter 83. As shown in FIG. 3 the output of counter 83 is decoded by decimal decoder 84 and controls the clock gating 86 and 88, respectively. The clock gating output is then in condition to receive either code numbers through the keyboard 22 or row codes to be stored in memory 91, respectively, depending on whether or not row code key switch 92 is in an open or closed position.

Similarly, the lock-out memory 56 is enabled through amplifier 53, lines 66, 76, 94, 95, OR gate 98, inverter 102, the output of which is fed through line 104 to clear counters 108 and 112. The output of counters 108 and 112 are utilized to sequentially step through the lock-out memory 56 so that if a number located in the random access memory 56 compares equally with a number entered on the keyboard 22, the forbiddden light 114 is energized and the number is rejected.

The third time counting circuit is enabled by clearing counter 25 through amplifier 53, lines 66, 76, 94, 120 to counter 25. This clear signal also clears flip-flop 122, the output of which is fed through an OR gate to both the reject light 21 and the third time light 123 through lines 124, 126 and 128, respectively. As shown, the door relay gate 27 is partially enabled through amplifier 53, lines 66, 76, 94, 120 and 134 which is one of the seven inputs to AND gate 26, the output of which, when the other conditions are met, energizes door relay 27.

As the card is inserted, optical readers 43 through 49 read seven columns. The columns read in the twenty by twenty matrix which makes up the interior of the card are determined by the column or Y matrix program 31 which is variable to read any seven of the twenty columns of the matrix. The output pulses from the seven columns are amplified with amplifiers 143 through 149 with the amplified signal being stored in latches 153 through 159. The output of the latches 153 through 156 are then gated into the scratch pad memory 54 as explained below.

When the card is between rows there are not bit signals, thus each of the inputs to OR gate 164 will be low. The low output of OR gate 164 is then inverted with inverter 168 creating the second high input signal to the AND gate 72. The output from AND gate 72 energizes one shot 74 which increments counter 171. The output of counter 171 is decoded by decimal decoder 174 and sets up output gates 176 so that the immediately preceding number is stored in the correct position in the card number storage memory 54. The output of one shot 74 is also fed to a second one shot 182 which serves as a delay to clock output gates 176. When the output of one shot 182 goes high the number is then stored in a correct location in the seven number memory 54. The output of one shot 182 is also fed to one shot 184, the output of which is ANDed with the output of the top optical reader which when it goes high, clears each of latches 153 through 159 to enable them to read the next number.

The bottom optical reader 51 turns off when the card is fully inserted. The output of bottom optical reader 51 is amplified by amplifier 191 and fed to AND gate 193 along line 196 and AND gate 194 along lines 196 and 197, respectively. If there were not seven card numbers read, a flip-flop 213 is set and the card release solenoid 18 is energized. This is accomplished as follows.

The output of the bottom optical reader is fed into an AND gate 193, the other input to which is the L-7 or last output from output gates 176 from counter 171. Thus, if the counter 171 has counted seven numbers and the bottom has been reached, the output of AND gate 193 will be high which sets flip-flop 199. The output of flip-flop 199 is connected to inverter 202 by lines 203, 204, 206 and 208 and the inverted or low input is fed into AND gate 194 along with the high input from the bottom optical reader. Thus, the output of the AND gate 194 remains low, flip-flop 213 is not set, and the card return solenoid 18 is not energized. If, however, seven numbers have not been counted, L-7 will remain low, thus the output of AND gate 193 will remain low and flip-flop 199 will not be set. Its output will therefore remain low. The output of inverter 202 will then be high and when it is combined with the output of the bottom optical reader at AND gate 194, it will set flip-flop 213, the output of which is fed to OR gate 216 by line 218. This will activate the card return solenoid 18 to return the card. It should be noted that the card return solenoid 18 is activated by each of the inputs to the OR gate 216 which comprise a key release switch 29, a remote release button 224, as well as the output of AND gate 26 which will return the card after the card has been accepted and the door relay 27 has been energized.

The accepted card signal 28 is connected to OR gate 216 from the output of AND gate 26 by lines 228 and 229. If seven numbers were read the security level comparator 232 is checked and if the security level is greater than the number assigned to the cardholder, an unauthorized light 240 is energized at the guard station, the door relay 27 is disabled and the reject light 21 is energized. This is accomplished in the following manner.

Optical readers 47 through 49 read bits corresponding to the security level of the cardholder. Only one row is read and by electrical connection this can be any row L-1 through L-7, that row being selected by connection of the one number memory 241 to one of the outputs L-1 through L-7 of output gates 176. The output of the security code memory 241 is compared with an assigned security level 243 having eight levels of security designated 0 through 7. The security level 243 and the number in memory 241 is compared with comparator 232 and the output of the comparator 232 is fed to an AND gate 234. The comparator 232 is set so that if the cardholder's security code entered into the memory 241 indicating the highest security level he can enter is less than the assigned security level setting 243 the output of the comparator 232 will go high. This output is fed to an AND gate 234 through line 236. The other input to the AND gate 234 is the output of the flip-flop 199 which is set when seven numbers have been read and the card has tripped the bottom optical reader 51. If both inputs are high the output of the AND gate 234 is fed through a driver 238 to a circuit which energizes an unauthorized light 240. In addition, the output of the AND gate 234 is fed through line 242 to an OR gate 244. The output of the OR gate is fed through a driver 246 to the reject lighting circuit and the reject light 21 is energized. The output of the AND gate 234 is also fed through lines 242 and 248 to an inverter 250 and the inverted signal, being a low signal, is then inputted to AND gate 26 which prevents all inputs signals from being high, thus disabling the output of AND gate 26, thereby preventing the door relay 27 from being energized.

In addition to the foregoing, if there is a positive indication that seven numbers were read, the clock circuit is partially enabled, the insert card light 13 is deenergized and the insert data light 15 is energized providing there was no reject or accept signal. The clock circuit is partially enabled from the output of flip-flop 199 through lines 203, 204, and 251 which is fed to AND gate 252, discussed below. The insert card light 13 is deenergized due to the signal fed from the output of flip-flop 199 through lines 203, 204, 206, 208 through inverter 202, the low output from inverter 202 being fed through line 254 through driver 258 to extinguish the insert card light 13. Finally, the insert data light 15 is energized due to the signal from flip-flop 199 being fed to AND gate 260 through lines 203, 204 and 206. The other two inputs to AND gate 260 are inverted signals from the reject light 21 and the reenergization circuit for the door relay 27 and accept light 28. From the reject light 21 the output of OR gate 244 is fed through lines 262, inverter 263 to the input of AND gate 260. Similarly, the accept light 28 energization circuit is connected by lines 228, 265, inverter 266 to the input of AND gate 260. Thus, when the output of both inverters are high it is an indication that neither the accept light 28 has been energized nor the reject light 21 and thus the third signal through line 206 indicating that the bottom has been reached and seven numbers were read, energizes the insert data light 15.

After the insert data light 15 has been lit, information can be fed into the circuit through the keyboard 22. The keyboard 22 is utilized for three purposes. By a cardholder, to enter the cardholder's memorized code number, and by the owner of the apparatus, to change the row code numbers and to enter forbidden numbers in the random access memory 56 which will prevent certain persons with a card from gaining access through the system. As noted above, modification of the circuit in the manner of the row code program may be made to enable the system owner to program the column matrix 31 as well. The keyboard 22 is keyed with a four digit decimal number which is decoded with a decimal to binary decoder 272 and stored in memory 58. It will be entered in either the code number memory 58, or the row code number memory 91. As indicated on the drawing and explained below, numbers may be keyed into the random access forbidden number memory 56 through the code number memory 58. If the row code key switch 92 is on, the row code memory 91 is enabled and the code number memory 58 is disabled. This is accomplished by feeding a positive signal through the row code key switch 92 into clock gating circuit 88 through lines 282, 283. The code number memory 58 is then disabled due to inverter 285 which disables the clock gating 86 through line 287. Conversely, if the row code switch 92 is off, the number memory 58 is enabled and the row code number memory 91 is disabled in the same manner.

At the end of the fourth number keyed into the keyboard 22, the keyboard 22 is disabled and the internal oscillator 288 is enabled. The keyboard 22 is disabled with the use of inhibit line 290. As each number is entered into the keyboard 22 the output of the decimal to binary decoder 272 is fed to OR gate 293 through lines 294 through 297. The output of the OR gate 293 fires a one shot 299, the output of which is fed to counter 83. The output of counter 83 is decoded by decimal decoder 84 and when the fourth digit has been entered, the signal on line 303 is fed back with line 290 to the one shot 299 to inhibit further counting. The internal oscillator 288 is enabled in a similar manner. As line 303 registers the entry of the fourth digit through keyboard 22, the signal is fed on line 306 to AND gate 252. Since all other inputs are now high, including the varying output of oscillator 288 which is fed to the AND gate 252 through line 310, the output of the AND gate 252 varies as the oscillator 288 varies. The output of the AND gate 252 is connected through line 312 to counter 316. The oscillator pulses are counted, decoded with decimal decoder 318 and used as clock signals, CK-1 through CK-4, to gate in the card number and keyboard number through output gating circuits 322 and 324. To assure that only four clock signals are received the fourth clock pulse is fed directly back to the AND gate along line 351 through inverter 353. The low output from the inverter disables the AND gate and thus no further oscillations are counted or decoded.

To obtain the random row code the numbers retained in the seven number memory 54 are not directly gated by the clock. Note also that each number of the user's secret number is compared individually with the number in the seven number memory 54 according to the four number program contained in the row code memory 91.

The first clock signal clocks output gating circuits 322 and 324 through lines 331, 332 and 333. The four bits which constitute the first of the user's four numbers from the code number memory 58 appear at the input of the comparator 336. The output of output gating 324 is dependent on the first number in the row code memory 91. That number determines which of row code one (RC-1) through row code seven (RC-7) will be enabled. The particular row code enable is then fed to the output gating 341 associated with the seven number memory 54. The four binary bits of that number are then gated to comparator 336. If the two numbers are not equal the output of comparator 336 goes high which sets a flip-flop 343, the output of which disables the door relay 27 and energizes the reject light 21. This is accomplished with line 345 which feeds the output of the flip-flop 343 to OR gate 244 to energize the reject light 21. In addition, the high output on line 345 is fed with line 347 to inverter 349 which creates a low input to AND gate 26, thereby disabling the AND gate 26 to prevent door relay 27 from being energized. Each of the four digits in the code number memory 58 are compared to the selected four numbers in the seven number memory 54 according to the row code contained in memory 91. If any of the four digits are unequal, the door relay 27 is disabled and the reject light 21 is energized in the manner described.

As explained above, the keyboard 22 may only be used three times. Each of the first two uses of the keyboard 22 are stored in the two place counter 25 by registering each of the first two occurences of the fourth clock pulse, the output of the counter being connected to AND gate 358. The fourth clock pulse is also fed directly over lines 350, 368 and 369 to partially enable AND gate 26 and is connected to AND gate 358 through lines 355 and 360. Therefore, the third time clock four occurs, the AND gate 358 is enabled and the high output then sets flip-flop 122 which is fed over lines 124, 126 to OR gate 244 to energize the reject light 21. In addition, the high output of flip-flop 122 is fed over lines 124, 128 to the third time light 123 and is fed over lines 124 and 334 to inverter 366 which disables AND gate 26 so that the door relay 27 cannot be energized.

Finally, a fourth clock pulse without a reject indicates that the two numbers are equal and enables the random access counting and gating circuit to begin the check for unauthorized numbers. This is accomplished through lines 368, 371 to AND gate 375. A second input to the AND gate 375 is from the zero detect circuit 377 which reads the counter 108, 112 outputs. Although the counters 108, 112 initially are cleared thus indicating a zero state, the zero detect circuit 377 is internally latched and is not enabled until a digit appears in the counters 108, 112. The low output of the zero detection circuit is inverted with line 379 and inverter 380 to enable AND 375.

The third input to the AND gate 375 is the oscillator 288 output which is fed to the AND gate 375 along lines 382 and 383. Since the output of the AND gate 375 will oscillate this output is fed along lines 386, 387, 388, 389, 390. Therefore, AND gate 375 gates in the internal oscillator 288 along line 386 to increment the counters 108, 112 with line 389. The oscillator pulses are also utilized to commmand the random access memory 56 to read with inputs along line 390. Thus each of the 64 sixteen bit words are clocked into the comparator 391. Since the contents of the four four bit code numbers are retained in memory 58 and are also inputted to the comparator along lines 392 through 399, the comparator 391 sequentially compares the user's code number with each of the forbidden numbers contained in the random access memory 56.

If the user's code number is contained in the random access memory 58, the comparator 391 output will go high and is fed with line 402 to AND gate 403 which sets a flip-flop 405. The output of the flip-flop 405 energizes the forbidden light 114 with driver 409. In addition, the reject light 21 is energized, the output of the flip-flop 405 being connected to OR gate 244 with line 412, and the door relay 27 is disabled with inverter 415, yielding a low signal and thus disabling AND gate 26.

If no equal condition is detected between the user's code number and the numbers contained in the random access memory 56, the address counters again read zero after the 64th word is read. When it reaches zero the zero detect 377 output goes high, this signal being inverted with inverter 380 which disables gate 375. This signal is also fed along lines 379, 417 to AND gate 26 which is the last enabling signal for the AND gate 26 and the door would now open if all other signals were true. The accept light 28 would be energized. In addition, the card return solenoid 18 would be energized. This is accomplished by the output of AND gate 26 being fed to OR gate 216 along lines 228 and 229, the output of OR gate 216 being utilized to energize card return solenoid 18 with driver 406.

To put a number into the random access memory 56, the memory key switch 424 is closed which enables the memory address counters 108, 112. The high output through memory key switch 424 is fed through lines 436, 437, 438 to clear two time counter 442. The counter initially has a low output which is inverted by inverter 444 and fed to the input of AND gates 446, 448 along lines 450 and 451, 454, respectively. The second enabling inputs to AND gates 446 and 448 from the memory key switch is fed along lines 436, 437, 456 to the input of AND gates 446, 448 along lines 458 and 460, respectively.

The desired address for random access memory 26 is then keyed into the keyboard 22.

The first address digit is entered into address counter 108 as follows. The decimal number is converted to four bit binary by decimal to binary decoder 272 and loaded into four number memory 58. At the time the entry of the first number is fed along line 297 to OR gate 293 which fires a one shot 299. The output of the one shot is counted by counter 83 and decoded by decimal decoder 84 which creates a clocking signal NL-1 from clock gating circuit 86. The clocking signal NL-1 causes the four binary digits contained in the first number location in memory 58 to be read on the four outputs N-1 through N-4 of output gating circuit 322. Since there are only 64 locations in random access memory 56, only the first three binary digits or N-1 through N-3 are fed to the input of counter 108. The NL-1 clock signal is also fed to the input of AND gate 446 which is the last enable for that AND gate. Consequently, the output of AND gate 446 is fed along lines 462 and 463 and used as the command signal to enter the three bit binary number into the counter 108. In addition, the output is fed along lines 462 and 465 to OR gate 467 to counter 442 indicating the first number has been entered.

In the same manner the second number entered into the keyboard 22 is clocked into counter 112 through AND gate 448 with the use of output NL-2 from clock gating circuit 86. The output of AND gate 448 is also fed to the counter 442 along lines 469 and 480 to OR gate 467 to the two bit counter 442. Since counter 442 is only a two bit counter with the entry of the second number, the output goes high, is inverted with inverter 444, and disables AND gates 446 and 448 through lines 450 and 451 and 454, respectively.

The keyboard 22 is then cleared with a clear button on the keyboard 22 and the desired four digit number is keyed in. The four bits are stored in four number memory 58, the contents of which is fed to the input of the random access memory 56, along lines 392 through 395, N-1 through N-4. At the completion of the fourth number, a one shot 478 is enabled from the decimal decoder 84 along lines 303, 306, 438 to AND gate 440, the second input to which is the closed memory key switch 424. The output of the one shot is fed along line 480 to command the random access memory 56 to write and retain the four digit sixteen bit word in the address location indicated by the address memory counters 108, 112 in the random access memory 56.

In general, while we have described a specific embodiment of our invention, it is to be understood that this is for purposes of illustration only and that various modifications can be made within the scope of the invention.

Claims

We claim as our invention:

1. A system for security control of a desired operation comprising:

a series of identification cards having individually distinct but nondiscrete information as a part of each card;

means for programming said system with a system program to read a random selection of information from the cards;

input means for entering the system program and for enabling a user to enter memorized information into the system;

information sensing means to read the random selection of information in accordance with the system program;

means for comparing the memorized information to the randomly selected information obtained from the cards to determine whether or not they are identical; and

means for implementing the desired operation if the memorized information and the randomly selected information are identical.

2. The system of claim 1 wherein the nondiscrete information associated with the identification cards is impregnated in the identification cards.

3. The system of claim 1 wherein the nondiscrete information associated with the identification cards is affixed to the surface of the identification cards.

4. The system of claim 1 wherein the nondiscrete information associated with the identification cards is arranged in a matrix configuration.

5. The system of claim 4 wherein the system can be programmed to read selected rows of the matrix in any order to establish a number to identify a user of the card.

6. The system of claim 4 wherein the system can be programmed to read selected columns of the matrix in any order to establish a number to identify a user of the card.

7. The system of claim 4 wherein the system can be programmed to read selected rows and columns of the matrix in any order to establish a number to identify a user of the card.

8. The system of claim 1 wherein the desired operation is to identify the user of the card for the purpose of providing credit thereto.

9. The system of claim 1 wherein the desired operation is to identify the user of the card for the purposes of controlling access to secured areas.

10. The system of claim 1 further comprising security level means for establishing various levels of security for the desired operation and wherein a portion of the nondiscrete information associated with the identification cards is related to the maximum level of security that the user may be permitted to obtain.

11. The system of claim 1 wherein the memorized information are numbers used to identify the user and further comprising storage means for storing numbers identifying users who will not be permitted to perform the desired operation;

means for comparing the memorized number with the stored numbers to determine whether or not they are identical; and

means for preventing the desired operation if the memorized number and the stored number are identical.

12. The system of claim 1 wherein the memorized information is a number and each digit of the user's memorized number is sequentially compared with each digit of a number selected by the system program from information associated with the identification card.

13. The system of claim 10 wherein the system may be programmed to obtain a multiple digit number having an identification component and a security level component from the nondiscrete information impregnated in each identification card.

14. The system of claim 10 wherein the desired operation can be accomplished at various levels of security and wherein the system may be programmed to obtain a multiple decimal digit number for identification of the user and a multiple octal digit number to determine at which security level the user may perform the desired operation.

15. The system of claim 14 wherein the system may be programmed to ignore all but one octal digit of the multiple octal digit number, the octal digit number being used to establish the maximum of eight levels of security that the user will be permitted to perform the desired operation.