VS1011E Datasheet, PDF (28/49 Pages) List of Unclassifed Manufacturers – MPEG AUDIO CODEC

VLSI
Solution ^y
VS1011e
VS1011E
8. FUNCTIONAL DESCRIPTION
8.3 Data Flow of VS1011e
SDI
Bitstream
FIFO
MP1 / MP2 /
MP3 / WAV /
ADPCM
decode
AIADDR = 0
User
Application
AIADDR != 0
SB_AMPLITUDE=0 ST_AMPLITUDE=0
Bass
enhancer
SB_AMPLITUDE!=0
Treble
enhancer
ST_AMPLITUDE!=0
Volume
control
SCI_VOL
Audio
FIFO
512 stereo
samples
L
S.rate.conv.
and DAC
R
Figure 13: Data Flow of VS1011e.
First, depending on the audio data, MPEG or WAV audio is received and decoded from the SDI bus.
After decoding, if SCI AIADDR is non-zero, application code is executed from the address pointed to
by that register. For more details, see VS10XX Application Note: User Applications.
Then data may be sent to the Bass and Treble Enhancer depending on SCI BASS.
After that the signal is fed to the volume control unit, which also copies the data to the Audio FIFO.
The Audio FIFO holds the data, which is read by the Audio interrupt (Chapter 10.9.1) and fed to the
sample rate converter and DACs. The size of the audio FIFO is 512 stereo (2×16-bit) samples, or 2 KiB.
The sample rate converter converts all different sample rates to CLKI/512 and feeds the data to the DAC,
which in order creates a stereo in-phase analog signal. This signal is then forwarded to the earphone
amplifier.
8.4 Serial Data Interface (SDI)
The serial data interface is meant for transferring compressed MP3 audio data as well as WAV data.
Also several different tests may be activated through SDI as described in Chapter 9.
Version 1.04, 2007-10-08
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