| CPC H04L 15/24 (2013.01) [H04L 9/3234 (2013.01); H04L 12/12 (2013.01)] | 20 Claims |

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1. A device capable of external activation comprising:
a light detection circuit adapted to receive a light signal from a light source;
a high pass filter coupled to the light detection circuit that when receiving light of at least a given intensity produces a spike;
a power manager chip coupled to the light detection circuit that upon receipt of the spike enables power to a microcontroller;
a component capable of inhabiting: a detection state in which:
a spike is detected; and when a spike is found, a spike counter is incremented;
a timer that measures a time between spikes;
wherein when the time between spikes exceeds an END OF WORD length, the spike counter is cleared;
wherein when the spike counter reaches a wakeup threshold then subsequent spikes and delay lengths are interpreted as a transmitted message; and
wherein the wakeup threshold is of sufficient length to allow the microcontroller to boot.
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