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/* Preparation of SD card and conversion of audio files */
The audio library uses a very trimmed SD library that uses the FAT only to find the start sector of the files. Therefore the file must be completely non-fragmented on the SD card. The best way to ensure this is to do a fresh and full format of the card (don't use quick format!). After formating the SD card, only copy new files on it. Don't delete files and avoid rename operations that creates file names that doesn't fit into 8.3 format (see http://en.wikipedia.org/wiki/8.3_filename ). All files must placed in root directory as folders are not supported by the audio library.
To convert audio filesI suggest the use of SoX from http://sox.sourceforge.net .
=== Windows users ===
Windows users should download from there the ZIP distribution and unzip it to the libraries/SimpleSDAudio/tools folder. Afterwards they can drag and drop .wav files to the appropriate batch files to start the conversion. The converted files will end up in folder "converted".
=== Linux users ===
Linux users should compile SoX from source or use their favorite package manager to install SoX. Afterwards they should use the following line for conversions:
<pre>
sox inputfile.wav --norm=-1 -e unsigned-integer -b 8 -r 31250 -c 1 -t raw outputfile.raw
</pre>
Change the following according to your needs:
* For stereo change -c 1 to -c 2
* For full rate use -r 62500 @ 16MHz, -r 31250 @ 8 MHz
* For half rate use -r 31250 @ 16MHz, -r 15625 @ 8 MHz
The option --norm=-1 is used to avoid bad sounding clipping effects.
== Hardware setup ==
