Data Sheet

PRELIMINARY
VS1063a Datasheet
9 FUNCTIONAL DESCRIPTION
9.8.10 SCI_AIADDR (RW)
SCI_AIADDR defines the start address of the application/plugin code that has been uploaded
earlier with SCI_WRAMADDR and SCI_WRAM registers. If no application code is used, this
register should not be written to, or it should be written zero.
Note: Reading SCI_AIADDR is not recommended.
For more details on how to write user applications and plugins, see VS1063 Programmer’s
Guide.
9.8.11 SCI_VOL (RW)
SCI_VOL is a volume control for the player hardware. The most significant byte of the volume
register controls the left channel volume, the low part controls the right channel volume. The
channel volume sets the attenuation from the maximum volume level in 0.5 dB steps. Thus,
maximum volume is 0x0000 and total silence is 0xFEFE.
Setting SCI_VOL to 0xFFFF will activate analog powerdown mode.
Example: for a volume of -2.0 dB for the left channel and -3.5 dB for the right channel: (2.0/0.5)
= 4, 3.5/0.5 = 7 → SCI_VOL = 0x0407.
Example: SCI_VOL = 0x2424 → both left and right volumes are 0x24 * -0.5 = -18.0 dB
In VS1063a bass and treble initialization and volume change is delayed until the next batch
of samples are sent to the audio FIFO. This delays the volume setting slightly. The hardware
volume control has zero-cross detection, which almost completely removes all audible noise
that occurs when volume is changed.
Note: After hardware reset the volume is set to full volume. Resetting the software does not
reset the volume setting.
9.8.12 SCI_AICTRL[x] (RW)
SCI_AICTRL[x] registers ( x=[0. . . 3] ) can be used to access the user’s application/plugin pro-
gram.
The SCI_AICTRL registers are also used as parameter registers when encoding audio. See
Chapter 10.7 for details.
For more details on how to write user applications, see VS1063 Programmer’s Guide.
Version: 0.42, 2011-11-24 49