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Subject: Re: Odd button behaviour (new info)

Re: Odd button behaviour (new info)

From: Jerry Van Baren <>
Date: Wed, 07 Dec 2005 16:18:06 -0500

The buttons are read by an A/D converter and are encoded by using
different voltage levels (different resistances connected to the
buttons). What you are probably running into is that you are at one end
of the "acceptable" range so, when your batteries are low, the button
decoder logic decodes a button as the wrong one.

My suggestion is to check for changes to the button voltage conversion
levels in button.c:

It could have been a side effect of changes in adc.c as well:


Ronald Teune wrote:

> Well, I'll just keep replying to myself, getting closer to the issue...
> First, I'll start with earlier misassumptions:
> * CBR/VBR has got nothing to do with it
> * "on time" has not directly got anything to do with it, but battery
> state does.
> A few days ago, I flashed back to rombox-20051127. The problems were
> gone. Until I turned on the unit yesterday: it almost immediately
> stopped playing again - my battery was down to about 10%. I tried
> ROLO'ing into ajbrec.ajz: no problems at all.
> Then I tried flashing rockbox.ucl, rebooting, and (of course - it
> still runs out of ram) no problems.
> Flashing rombox, rebooting, it immediately turned off. Then I turned
> it on again, and with a quick press on F2 prevented it from turning
> off again. Another press on F2 returned me to the WPS. 2 presses on
> the "on" key got me to the tree view, then back to the wps again, and
> after that it showed "Press OFF to shut down" => the off key was
> triggered 2 times!
> Then flashing rockbox.ucl again: problems were gone.
> Summary:
> Somewhere between rombox-2.5 and rombox 20051127 and probably after
> October (I forgot what I ran before) there have been changes in
> rockbox, causing my unit to behave oddly, triggering the OFF button
> after another button, about 90% of the times. But only when ran
> directly out of flash, and only at low battery. Perhaps some timing
> issues?
> And now just hope this additional info is meaningful to someone...
> Kind regards,
> a somewhat less puzzled Ronald...
> On Sun, 04 Dec 2005 15:30:57 +0100, Ronald Teune <> wrote:
>> Hi,
>> It seems that no other user has this problem, or they just don't use
>> the daily builds or read the list. I did some additional testing.
>> * it seems that the button behaviour is quite right, just after the
>> unit is turned on. If the unit's been on for about an hour, maybe
>> two (when it's "warmed up"), the problems as described start: after
>> a short or long keypress on the left/right/up/down/on button, an
>> "off" event is somehow generated. When constantly pressing other
>> buttons (scroll through lists, etc), the off event doesn't seem to
>> come through. When turning the unit off at that point, and then
>> turning it on again, it triggers an off event just after resuming,
>> so music stops again. The only "solution" to keep the music playing
>> is to press F2 or F3 after resuming the music, because these are the
>> only places that don't exit at the off button.
>> * at a point like this, I loaded the 2.5 firmware: problems were
>> gone. Turning off and on, thus loading the newer firmware again,
>> made the problems return. So... was it perhaps because it was
>> flashed? No; I then flashed the 2.5 firmware, and still no problem.
>> All the time I made sure the same config file was being used, so no
>> different settings (perhaps apart from some new features). Now I'm
>> using a flashed 2.5 for some time, without problems.
>> * I searched through the commits-since-2.5 for "button", but
>> couldn't find anything pointing into this direction.
>> Am I really the only one with such an odd unit?
>> Ronald
Received on 2005-12-07

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