Electronic access control device utilizing a single microcomputer intergrated circuit
An electronic lock utilizes two microprocessors remote from each other for enhanced security. The first microprocessor is disposed close to an input device such as a keypad, and the second microprocessor is disposed close to the lock mechanism and well protected from external access. The first microprocessor transmits a communication code to the second microprocessor when it receives via the input device an access code that matches a preset access code. The second microprocessor opens the lock if the transmitted communication code matches a preset communication code. The dual-microprocessor arrangement is advantageously used in a voice controlled access control system and in a motorcycle ignition control system. The present invention further provides an electronic access control system which has a master electronic key having a preset number of access, and an electronic alarm system for a bicycle that has a remote control mounted in the helmet of the rider.
1. A method comprising the steps of:
deactivating a circuit during a first time period;
enabling a portion of the circuit for a second time period;
sensing an electromagnetic signal during the second time period;
enabling the circuit for an extended time period that is greater than the second time period upon the sensing of the electromagnetic signal;
processing the electromagnetic signal during the extended time period to obtain an input code;
comparing the input code to an access code;
providing a signal to unlock a device if the input code matches the access code; and,
receiving another input code from a keyboard and comparing the other input code to the access code or another access code.
2. The method of claim 1 further comprising the step of receiving a signal in response to pressing a program key on the keyboard.
3. A method comprising the steps of:
deactivating a circuit during a first time period;
enabling a portion of the circuit for a second time period;
sensing an electromagnetic signal during the second time period;
enabling the circuit for an extended time period that is greater than the second time period upon the sensing of the electromagnetic signal;
processing the electromagnetic signal during the extended time period to obtain an input code;
comparing the input code to an access code;
providing a signal to unlock a device if the input code matches the access code; and,
enabling a low-battery detection circuit for measuring a battery voltage during a first time period, and disabling the low-battery detection circuit during a second time period.
4. A method comprising the steps of:
deactivating a circuit during a first time period;
enabling a portion of the circuit for a second time period;
sensing an electromagnetic signal during the second time period;
enabling the circuit for an extended time period that is greater than the second time period upon the sensing of the electromagnetic signal;
processing the electromagnetic signal during the extended time period to obtain an input code;
comparing the input code to an access code;
providing a signal to unlock a device if the input code matches the access code; and,
providing a non-zero power output to the device, providing a lower non-zero power output to the device, and transitioning from the non-zero power output to the lower non-zero power output.
5. A method comprising the steps of:
deactivating a circuit during a first time period;
enabling a portion of the circuit for a second time period;
sensing an electromagnetic signal during the second time period;
enabling the circuit for an extended time period that is greater than the second time period upon the sensing of the electromagnetic signal;
processing the electromagnetic signal during the extended time period to obtain an input code;
comparing the input code to an access code;
providing a signal to unlock a device if the input code matches the access code;
writing the access code into a memory in response to a write signal received through a communication port; and,
writing a serial number into the memory.
6. The method of claim 5 further comprising the step of transmitting the serial number through the communication port.
7. A method comprising the steps of:
periodically enabling and disabling a circuit during each of a plurality of duty cycles wherein the circuit is enabled for a time t 1 during each of the duty cycles;
receiving an input code transmitted via an electromagnetic signal;
comparing the input code to an access code;
enabling the circuit as the input code is being received for a time t 2 that is greater then said time t 1 ;
providing a signal to unlock a device if the input code matches the access code; and,
receiving another input code from a keyboard and comparing the other input code to the access code or another access code.
8. The method of claim 7 further comprising the step of receiving a signal in response to pressing a program key on the keyboard.
9. A method comprising the steps of:
periodically enabling and disabling a circuit during each of a plurality of duty cycles wherein the circuit is enabled for a time t 1 during each of the duty cycles;
receiving an input code transmitted via an electromagnetic signal;
comparing the input code to an access code;
enabling the circuit as the input code is being received for a time t 2 that is greater then said time t 1 ;
providing a signal to unlock a device if the input code matches the access code; and,
periodically enabling and disabling a low-battery detection circuit for measuring a battery voltage.
10. A method comprising the steps of:
periodically enabling and disabling a circuit during each of a plurality of duty cycles wherein the circuit is enabled for a time t 1 during each of the duty cycles;
receiving an input code transmitted via an electromagnetic signal;
comparing the input code to an access code;
enabling the circuit as the input code is being received for a time t 2 that is greater then said time t 1 ;
providing a signal to unlock a device if the input code matches the access code; and,
providing a non-zero power output to the device, providing a lower non-zero power output to the device, and transitioning from the non-zero power output to the lower non-zero power output.
11. A method comprising the steps of:
periodically enabling and disabling a circuit during each of a plurality of duty cycles wherein the circuit is enabled for a time t 1 during each of the duty cycles;
receiving an input code transmitted via an electromagnetic signal;
comparing the input code to an access code;
enabling the circuit as the input code is being received for a time t 2 that is greater then said time t 1 ;
providing a signal to unlock a device if the input code matches the access code;
writing the access code into a memory in response to a write signal received through a communication port; and,
writing a serial number into the memory.
12. The method of claim 11 further comprising the step of transmitting the serial number through the communication port.
13. A method for operating a circuit on current drained from a battery comprising the steps of:
generating a signal to indicate detection of a device capable of providing an electromagnetic signal;
receiving an input code transmitted by the electromagnetic signal;
increasing the current drained from the battery;
comparing the input code to an access code;
providing an output to an unlock device if the input code matches the access code;
decreasing the current drained from the battery after receiving the input code; and,
receiving another input code from a keyboard and comparing the other input code to the access code or another access code.
14. The method of claim 13 further comprising the step of receiving a signal in response to pressing a program key on the keyboard.
15. A method for operating a circuit on current drained from a battery comprising the steps of:
generating a signal to indicate detection of a device capable of providing an electromagnetic signal;
receiving an input code transmitted by the electromagnetic signal;
increasing the current drained from the battery;
comparing the input code to an access code;
providing an output to an unlock device if the input code matches the access code;
decreasing the current drained from the battery after receiving the input code; and,
further comprising the steps of periodically enabling and disabling a low-battery detection circuit for measuring a battery voltage.
16. A method for operating a circuit on current drained from a battery comprising the steps of:
generating a signal to indicate detection of a device capable of providing an electromagnetic signal;
receiving an input code transmitted by the electromagnetic signal;
increasing the current drained from the battery;
comparing the input code to an access code;
providing an output to an unlock device if the input code matches the access code;
decreasing the current drained from the battery after receiving the input code; and,
providing a non-zero power output to the unlock device, providing a lower non-zero power output to the unlock device, and transitioning from the non-zero power output to the lower non-zero power output.
17. A method for operating a circuit on current drained from a battery comprising the steps of:
generating a signal to indicate detection of a device capable of providing an electromagnetic signal;
receiving an input code transmitted by the electromagnetic signal;
increasing the current drained from the battery;
comparing the input code to an access code;
providing an output to an unlock device if the input code matches the access code;
decreasing the current drained from the battery after receiving the input code;
writing the access code into a memory in response to a write signal received through a communication port; and,
writing a serial number into the memory.
18. The method of claim 17 further comprising the step of transmitting the serial number through the communication port.