Test firmware

Richard A. Smith richard at laptop.org
Sat Oct 24 00:00:45 EDT 2009


> When this happens to me I unplug it, remove the battery  then hold the power 
> button about 10secs.  Put the battery back in and all is good

The button press is unnecessary.

The EC reads the power button and with no battery and no power you got no EC.  Even if you did have some brief amount of EC while a cap discharged the power button signal is a one shot and holding it longer than about 200 ms will not do anything more until  4 seconds.  At 4 seconds the EC turns off the voltage regulators to the host and waits for you to release the button before restarting the state machine that runs the button logic.

Waiting 10 seconds is still a good idea to make sure all the caps have discharged but holding the power button will have no effect on how long that takes.

-- 
Richard A. Smith  <richard at laptop.org>
One Laptop per Child


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