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adding a servo

Since I don't have any lock that works based on a digital signal, it seemed appropriate to at least have something in place that would emulate the behavior of such a lock, and I thought that a servo would be a good substitute.

(note: a servo is a device with which one can control a specific rotational position)

Connecting a servo to the current circuit isn't too much of a challenge, as it just requires a single output connection along with the ground/power.


Making the servo also just requires an addition of a few lines of code, using the Servo library.

A simple video of the servo in action:



Now, at least with a locking behavior in place, the one visible functionality that needs to be addressed is the device's ability to distinguish between a "standby" state (no alcohol/no breathing in: should be in "lock" mode) and a "open" state (no alcohol/breathing in: should be in "open" mode).
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