I’m in a fit of over-design. Here I am on the sixth edition of Flavonoid, which is going rather well. It does pretty much everything I would like it to do, save a proper rest mode, some little bit of recoding to make it more fuel efficient, a pedometer (step-counting) mode per Dennis’ request and, well — mostly commissioning a proper enclosure of some sort for it.
And then I had a number of things that sort of bugged me. One was the relatively low level of oomph with which the device could charge over USB. So, I started thinking about a number of power-related things. One idea (that the seventh edition will have) is a low-battery circuit that’ll allow the device to go to sleep when the battery is so low that it should be charged. For that I’m trying out the MAX6439 to raise a flag when the battery starts to bottom-out. Then I started thinking about a non-fixed battery — one that could be replaced and recharged in a normal recharger. So, I added that. Then I started thinking about a non-fixed battery being put in wrong way ’round which would definitely blow out the LDO regulator I’m using which isn’t, like..so great — so I added a little circuit using the MAX4636 CMOS switch to quickly fix that situation. Then there was the kind of annoyance of the real-time clock loosing track of time when power is removed — so I added a coin cell to keep the real-time clock juiced even when the proper battery has gone flat. And I knuckled into my own weird design fetish about things that don’t turn off and added a switch..so Flavonoid can be turned off..but it’s a very very small switch so maybe I won’t turn it off except in weird situations, like getting on an airplane or whatever.
I took off the reset pushbutton because I realized I was never hitting reset, pretty much. I left two plated holes so I could put a little reset jig together if I needed to, which I won’t, cause I can now turn the thing off and then on, or reset it any number of other ways. Here is the layout for version 7, now somewhere in China coming to be.
Lately I’ve been walking around with one on my hip and one in my pocket to capture some data. I wrote a little Python script that connects to the Flavonoid over USB, grabs the data and then tosses it up to the Flavonoid mothership database. I’ve also started jotting down how many steps the pedometer says for the day. I’m comparing pedometer steps to Flavonoid “data points” just for grins and to check for any correlation or consistency. These days, I’m not particularly physically active — I move back and forth between the bench and the desk, spend a few days a week doing more or less the same at Nokia — and that’s pretty much it. But, hopefully when others get theirs or if I try and do anything other than “test” myself, some insights will develop.
I’d actually be more interested in seeing some cool offline gaming style games develop..