ONKEY interrupt is trapped in PMU occasionally on resuming

[Werner Almesberger]

Harald Welte wrote:
> I am not surprised.  At the time where we didn't yet have GTA01
> batteries and were powering with a 4.2V linear regulator on the battery
> terminals, the system was quite ustable, too.

One difference between using a battery and a regulator (be it that
external one we used to use such a long time ago, or just a bench
supply), is the response to rapid load changes.

The battery should basically go straight from one steady state to
the next, while a regulated supply will drop a bit if the load
suddenly increases, and overshoot if the load drops.

So much about the theory. I've actually tried to measure the
load transient response of my various power sources, and they all
look suspiciously similar. Needs some more looking into at some
point in time ...

- Werner