摘要 |
A security system comprises a card containing access information, a reader for reading the card, a power source, a locking mechanism, and a first circuit for operating the locking mechanism. The power source is coupled to the first circuit to provide power to the first circuit. The power source is also coupled to a wake-up circuit to provide power to the wake-up circuit. The wake-up circuit detects the presence of an object and enables the reader to ascertain whether the object is the card. A method for operating the security system comprises first determining that electromagnetic energy is not being detected by the wake-up circuit, then determining that electromagnetic energy is being detected by the wake-up circuit, then determining that electromagnetic energy is not being detected by the wake-up circuit, and then ascertaining whether the object is the card.
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