CPC H04R 29/00 (2013.01) | 18 Claims |
1. A system, comprising:
a sound sensor; and
re-programmable and/or reconfigurable analog circuitry configured to monitor an acoustic signal sensed by the sound sensor and selectively generate a tone detection signal in response to an analysis of the acoustic signal and presence of at least one pre-determined tone frequency, and
a digital Microcontroller Unit (“MCU”), coupled to the analog circuitry, that receives the tone detection signal as a digital tone detection signal interrupt that causes the MCU to awake from a low power state and create a digital timestamp at each rising and falling edge of the tone detection signal.
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