From 18ca2123b6c3464f33801f182d1be780fcc0cca4 Mon Sep 17 00:00:00 2001 From: Buschel Date: Mon, 29 Mar 2010 17:58:17 +0000 Subject: [PATCH] Add new section 'Optimising battery runtime' to the manual (FS#11148). git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25382 a1c6a512-1295-4272-9138-f99709370657 --- manual/advanced_topics/main.tex | 95 +++++++++++++++++++++++++++ manual/configure_rockbox/display_options.tex | 4 +- manual/configure_rockbox/playback_options.tex | 4 +- manual/configure_rockbox/system_options.tex | 4 +- 4 files changed, 101 insertions(+), 6 deletions(-) diff --git a/manual/advanced_topics/main.tex b/manual/advanced_topics/main.tex index 47d4305f7..b13a76712 100644 --- a/manual/advanced_topics/main.tex +++ b/manual/advanced_topics/main.tex @@ -580,3 +580,98 @@ current version. \opt{archos}{\input{advanced_topics/archos-flashing.tex}} +\section{Optimising battery runtime} + Rockbox offers a lot of settings that have high impact on the battery runtime + of your \dap{}. The largest power savings can be achieved through disabling + unneeded hardware components -- for some of those there are settings + available. +\opt{swcodec}{ + Another area of savings is avoiding or reducing CPU boosting + through disabling computing intense features (e.g. sound processing) or + using effective audio codecs. +} The following provides a short overview of the most relevant settings and + rules of thumb. + +\nopt{ondio}{ +\subsection{Display backlight} + The active backlight consumes a lot of power. Therefore choose a setting that + disables the backlight after timeout (for setting \setting{Backlight} see + \reference{ref:Displayoptions}). Avoid to have the backlight enabled all the + time. +} + +\opt{lcd_sleep}{ +\subsection{Display power-off} + Shutting down the display and the display controller saves a reasonable amount + of power. Choose a setting that will put the display to sleep after timeout + (for setting \setting{Sleep} see \reference{ref:Displayoptions}). Avoid to + have the display enabled all the time -- even, if the display is transflective + and is readable without backlight. Depending on your \dap{} it might be + significantly more efficient to re-enable the display and its backlight for a + glimpse a few times per hour than to keep the display enabled. +} + +\opt{accessory_supply}{ +\subsection{Accessory power supply} + As default your \dap{}'s accessory power supply is always enabled to ensure + proper function of connected accessory devices. Disable this power supply, if + -- or as long as -- you do not use any accessory device with your \dap{} while + running Rockbox (see \reference{ref:AccessoryPowerSupply}). +} + +\opt{lineout_poweroff}{ +\subsection{Line Out} + Rockbox allows to switch off the line-out on your \dap{}. If you do not need + the line-out, switch it off (see \reference{ref:LineoutOnOff}). +} + +\opt{spdif_power}{ +\subsection{Optical Output} + Rockbox allows to switch off the S/PDIF output on your \dap{}. If you do not + need this output, switch it off (see \reference{ref:SPDIF_OnOff}). +} + +\opt{disk_storage}{ +\subsection{Anti-Skip Buffer} + Having a large anti-skip buffer tends to use more power, and may reduce your + battery life. It is recommended to always use the lowest possible setting + that allows correct and continuous playback (see \reference{ref:AntiSkipBuf}). +} + +\opt{swcodec,disk_storage,flash_storage}{ +\subsection{Audio format and bitrate} +\opt{swcodec}{ + In general the fastest decoding audio format will be the best in terms of + battery runtime on your \dap{}. An overview of different codec's performance + on different \dap{}s can be found at \wikilink{CodecPerformanceComparison}. +} + +\opt{flash_storage}{ + Your target uses flash that consumes a certain amount of power during access. + The less often the flash needs to be switched on for buffering and the shorter + the buffering duration is, the lower is the overall power consumption. + Therefore the bitrate of the audio files does have an impact on the battery + runtime as well. Lower bitrate audio files will result in longer battery + runtime. +} +\opt{disk_storage}{ + Your target uses a hard disk which consumes a large amount of power while + spinning -- up to several hundred mA. The less often the hard disk needs to + spin up for buffering and the shorter the buffering duration is, the lower is + the power consumption. Therefore the bitrate of the audio files does have an + impact on the battery runtime as well. Lower bitrate audio files will result + in longer battery runtime. +} + + Please do not re-encode any existing audio files from one lossy format to + another based upon the above mentioned. This will reduce the audio quality. + If you have the choice, select the best suiting codec when encoding the + original source material. +} + +\opt{swcodec}{ +\subsection{Sound settings} + In general all kinds of sound processing will need more CPU time and therefore + consume more power. The less sound processing you use, the better it is for + the battery runtime (for options see \reference{ref:configure_rockbox_sound}). +} diff --git a/manual/configure_rockbox/display_options.tex b/manual/configure_rockbox/display_options.tex index f416e8418..23673e248 100644 --- a/manual/configure_rockbox/display_options.tex +++ b/manual/configure_rockbox/display_options.tex @@ -60,8 +60,8 @@ \item[Sleep (After Backlight Off).] This setting controls how long rockbox will wait before turning off the display after the backlight is turned off. Turning off the display - saves a little bit of battery power but turning on the display takes - noticeably longer than just turning on the backlight. + saves battery power but turning on the display takes noticeably longer + than just turning on the backlight. } \opt{backlight_brightness}{ diff --git a/manual/configure_rockbox/playback_options.tex b/manual/configure_rockbox/playback_options.tex index 8ac9548ea..5f61b0b0e 100644 --- a/manual/configure_rockbox/playback_options.tex +++ b/manual/configure_rockbox/playback_options.tex @@ -62,7 +62,7 @@ you to configure settings related to audio playback. The setting \setting{FF/RW Min Step} controls the initial speed and \setting{FF/RW Accel} controls the acceleration. \opt{disk_storage}{ - \section{Anti-Skip Buffer} + \section{\label{ref:AntiSkipBuf}Anti-Skip Buffer} This setting controls how early Rockbox starts refilling the music buffer from the hard drive when playing. A longer Anti-Skip Buffer helps prevent skips in music playback if Rockbox has trouble reading from the disk. @@ -204,7 +204,7 @@ you to configure settings related to audio playback. }%\opt{swcodec} \opt{spdif_power}{ - \section{Optical Output} + \section{\label{ref:SPDIF_OnOff}Optical Output} Enables or disables the optical S/PDIF output to allow a digital connection to a suitable external decoder. To enable optical output, set to \setting{Yes} diff --git a/manual/configure_rockbox/system_options.tex b/manual/configure_rockbox/system_options.tex index d2eb992b8..af7695ed4 100644 --- a/manual/configure_rockbox/system_options.tex +++ b/manual/configure_rockbox/system_options.tex @@ -152,7 +152,7 @@ This sub menu relates to limits in the Rockbox operating system. } \opt{accessory_supply}{ -\subsection{Accessory Power Supply} +\subsection{\label{ref:AccessoryPowerSupply}Accessory Power Supply} This option turns the accessory power supply \setting{On} and \setting{Off}. The Apple accessory protocol has been partially implemented in Rockbox, and thus there is a reasonable chance that your favourite accessory will work. @@ -162,7 +162,7 @@ this option \setting{On}. If it is not required, then turning this setting } \opt{lineout_poweroff}{ -\subsection{Line Out} +\subsection{\label{ref:LineoutOnOff}Line Out} This option turns the \dap{}'s line-out \setting{On} and \setting{Off}. On some devices an enabled line-out will consume some power even if not used. If it is not required, then turning this setting \setting{Off} will save battery and -- 2.11.4.GIT