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Rockbox mail archiveSubject: Re: Use SLEEP instruction for longer (?) runtimeRe: Use SLEEP instruction for longer (?) runtime
From: Andrew Jamieson <andrew.jamieson_at_projectlab.net>
Date: Wed, 22 Jan 2003 09:29:50 +1100 If you can get me a compiled AJB version, I can create an extended data table of current consumption over an arbitary period of time (~ 3 samples per second), or graph it really acurately over a shorter period of time (with a DSO). Andrew Jamieson ----- Original Message ----- From: "Simon Elén" <simel346_at_student.liu.se> To: <rockbox_at_cool.haxx.se> Sent: Wednesday, January 22, 2003 8:40 AM Subject: Re: Use SLEEP instruction for longer (?) runtime > Björn Stenberg wrote: > > Yeah, I was curious about your choice of method. We have discussed > > this method previously, but rejected it since so very little time (a > > fraction of a tick) is actually spent sleeping. > > True, but not very much is done before it goes to sleep again. Also, when > playing it still needs to wake up every 1ms to poll the MAS, right? > > > We didn't think it > > would make any noticeable difference on power use. Have you made any > > measurements? > > Since I've just made the patch, I haven't been able to check the runtime > yet. I was hoping someone would have a more exact way of checking it, since > runtime varies by at least an hour depending on the bitrate of the MP3:s I > play. > > Try compiling with USE_LED_FOR_CPU_BUSY #defined. This is probably a grossly > inaccurate way of checking, but it was the best debugging aid I could come > up with. I just tried inverting it to make it light up when sleeping instead > of when busy, and it is generally brighter this way. This should at least > indicate that the CPU is sleeping more than half of the time, which should > already have some impact on the power consumption. I welcome any better > ideas for checking this without opening the Archos. > > > The more efficient, but also more difficult, solution is to rewrite > > the scheduler to use a sorted sleep queue with a timeout for each > > thread and a wakeup timer interrupt. That way we can sleep for farily > > long periods of time. (At least on Recorder.) > > And at least while not playing, unless we can successfully guess when the > MAS will want more data sent to it. > > -- > Simon Elén > > Received on 2003-01-21 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |