On Fri, 10 Oct 2008 01:01:14 +0100, Rui Miguel Silva Seabra <[EMAIL PROTECTED]> wrote: > Hi, > > Big question: > Are the accelerometers constantly draining battery life? > > or... > > The rate at which they feed me data only starts up when the file > handle is opened, and stops when it's closed? > > If it's the first case, then the init scripts should shut both > accelerometers down as soon as possible, and software that uses them > should turn them on as needed.
AFAIK by default they're always powered up. Certainly apart from the times I hit 'dead accelerometers' that took a few reflashes to get going again, I've never had to power them up unless I'd previously powered down. According to the datasheet at http://wiki.openmoko.org/wiki/ST_LIS302DL: Symbol Parameter Test conditions Min.Max.Unit Idd Supply current T = 25°C, ODR=100Hz 0.3 0.4 mA IddPdn Current consumption in T = 25°C 1 5 μA power-down mode So the power draw is pretty low, both together being less than one milliamp. I suspect that frameworkd will be able to shut them down automatically if nothing needs them, once accel support is incorporated. (IIRC it does that now for other subsystems, like gps) j _______________________________________________ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community