Streamit Lisa Compact, Руководство пользователя

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Lisa Compact 38
This fallback implementation for both playlist presets and fallback to card is depicted in the figure below.
Suppose the Lisa was playing preset 2, an internet audio stream (say dance music, not a playlist).
When the internet connection is experiencing problems the device will enter the fallback mode. Preset 2
was the last preset that was being played before entering fallback, hence the name Last Played Station
(LPS).
As a first step, the Lisa will check if the matching fallback playlist (2.pls) is valid on the card.
Especially for bad connection the device can enter fallback many times per day. You also want to make
sure that not the same entries are being played over and over again when in fallback. The Lisa solves
this issue by playing the fallback playlist starting with a random entry.
If the fallback playlist (the playlist with the ID same as the LPS, in our case 2.pls) is not OK is not valid
on the card, the Lisa will start to play as default playlist 1.pls at random.
Note that for proper operation of the fallback to card, the preset URL must point directly to an audio
stream. If the preset URL actually points to a playlist that contains several audio stream URLs, the Lisa
will try the next URL in the playlist in case of problems with the stream. However, if the internet
connection itself is failing, this will not help.
8.2 Set up the Lisa for fallback
This section describes in detail a minimal setup to make the Lisa fallback and play from the SD card in
case of network or streaming failure. It is assumed that the Lisa has a preset 1 configured to play an
audio stream.