Sorry, this post won’t contain awesome pictures of Pokeballs like PLUME! This afternoon was more hardware searching than 3D printing for Drops N’ Roses. We spent a long time talking with Alexis, Sam and Tarik about our memory needs and their cost. FRAM seemed quite interesting, but it is very expensive compared to our needs. We computed life expectancies based on consumption in standby mode and concluded that we would probably use an extern flash memory of 16 or 64 Mb (ensuring a 13 year autonomy with a button cell… if nobody reads nor writes anything, of course!), for a very low price: around $3!
Another very fun idea came to us this afternoon: considering that some drops will be in the outside or behind a window and considering the pins we wanted to add for connecting any external device… why couldn’t we connect a pocket calculator solar panel? With that, a (rechargeable) button cell could really last several years! Sadly, it won’t work for the underground. But it isn’t a bad idea either, and we will think about it.