Patent ID: 7844837

Claim:
An electronic device comprising: a housing; a tamper sensor carried by said housing and configured to detect tampering with the electronic device and to generate a tamper event signal based thereon; and an electronic timer connected to said tamper sensor and comprising: a clock reference signal generator configured to generate a clock reference signal, a real time clock (RTC) circuit configured to generate real time data based upon the clock reference signal, said RTC circuit comprising: a plurality of registers configured to store respective bits of the real time data, each register comprising: a master latch configured to initially store a real time data bit, a slave latch configured to subsequently store the real time data bit, and a user latch configured to store the real time data bit from said slave latch, and a controller configured to cause at least some of said plurality of registers to increment based upon the clock reference signal, and a tamper circuit configured to receive the tamper event signal from said tamper circuit and to cause said user latches to hold current real time data bits based thereon until said tamper circuit is reset by a user; wherein said user latches thus providing user accessible real time data when the tamper event signal does not indicate tampering has occurred, and providing a user accessible time stamp when the tamper event signal does indicate tampering has occurred.