[Noisebridge-discuss] Long-lived, battery-powered AVRs

[Casey Callendrello]

What about using the gate latch to trigger a Polou switch?
(http://www.sparkfun.com/products/8903). This was used by the famous
Reverse Geocache to save battery life. It's a clever little switch that
can be used to let a microcontroller turn itself off. When off, it draws
(according to spec) .01ua.

--Casey

On 01/30/2012 12:47 AM, Jonathan Lassoff wrote:
> I'm interested in helping someone I know with a project to build a
> remote AVR-based sensor (arduino parts) that will use an Xbee to
> detect a gate latch opening and closing. Since it's in a bit of a
> remote spot, it has to be battery powered.
>
> As we're brainstorming ways of saving power, we thought of a couple of
> ways of not keeping things powered all the time:
>
>  - Use CPU sleep on the AVR so as to only periodically wake up and
> poll the state of the gate sensor. I think the Xbee would still draw a
> bit of power still.
>  - Use a transistor that can trigger a flip flop with a transient
> amount of power from a coil in the sensor, and use that state to
> switch the AVR on, and have it turn itself back off, once done
> signaling.
>
> I'm sure there's been some past work on remote AVR sensors before, but
> I can't find anything that seems quite like what we're trying to do.
>
> Any advice on something like this?
>
> Cheers,
> jof
> _______________________________________________
> Noisebridge-discuss mailing list
> Noisebridge-discuss at lists.noisebridge.net
> https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss