Moment of panic yesterday when I thought it might not be possible to power up this baby parasitically as I hoped. That's an important feature of this project because of the environment it needs to be deployed in - no direct power source can be made available in an elegant fashion.
I was really glad to find that there's enough to drive the basic behaviour I need.
Ideally I'd be able to drive a flashing LED too. Wondering at this stage if I can drop the microcontroller as it's hard to build the right kind of circuit for minimal energy use, and the final behaviour I'm thinking of doesn't really justify the complexity of programming it.
I found this discussion provided some useful pointers how to create an analog circuit which will probably do what I need.
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