I'm evaluating COM options for a complex system where power efficiency
is crucial (existing Blackfin hardware wakes approximately 1 second in 30)
The Sakoman article on OMAP power management is an excellent exposition.
It suggests that an Overo Water plus Thumbo consumes about 35mw in
shutdown mode which makes it competitive with the Blackfin hardware.
Some questions arising are:
1. The Blackfin processors have a wake-up timer which will restore the
processor from deep sleep. Is there a similar ability in 3530? I cannot
make it out from the TI documentation.
2. What is the best off-the-shelf distribution for low power/power
adjustment facilities. At this stage I'd prefer something I can work
with rather than configure and build from scratch :)
3. If the system is powered down, does anyone know how quickly it can be
restored? I'm assuming state is maintained in SDRAM in self-refresh mode
 My mistake, you were referring to deep sleep [/edit]
Hi Jerry, I am not sure if I understand it correctly, but I think your first question is answered in the same Sakoman's article that you are referring to. Half way through the article:
If it is desired to bring the system back to life after a set time interval (say 5 seconds), you could do that with:
# mkdir /debug
# mount -t debugfs debugfs /debug
# echo 5 > /debug/pm_debug/wakeup_timer_seconds
# echo mem > /sys/power/state
On 23/05/2012 20:08, adam.yh.lee wrote:
> If it is desired to bring the system back to life after a set time interval
> (say 5 seconds), you could do that with:
> # mkdir /debug
> # mount -t debugfs debugfs /debug
> # echo 5> /debug/pm_debug/wakeup_timer_seconds
> # echo mem> /sys/power/state
Ah. I missed that. Do you know if this still works from deep-sleep?
(Waiting for hardware to arrive so cannot test this out!)