6. Evaluation Mode Operation
18
Seiko Epson Corporation
S1V30000 Series Graphical User Interface
Application (Rev 3.01)
6.1.2.2 Sample
Rate
The Sample Rate Drop-box
is used to configure the output sample rate of the
DAC. Most applications choose their own sample rate, so the default “Set by
Application” option should be used. The “Set by Application” option cannot be
used with the
”I
2
S In to DAC” routing, since a defined sample rate is required for the
incoming I
2
S data.
Note that in some cases, the sample rate may be incompatible with the ADC
sample rate and an error will be reported in the System Message Window.
6.1.2.3 Clock
Source
The Clock Source Drop-box
is used to select the clock source for S1V30xxx.
The default is to use an internally generated clock source. For synchronising
with external clock sources (mainly applicable to I
2
S data transfer), the External
Option can be used. Refer to the Evaluation Board User Guide supplied with
the Evaluation Kit for details on connecting an external clock.
6.1.2.4 Amplifier
The Amplifier drop-box is used to select the path over which output audio is
routed on the target. On the evaluation boards, both the “LINE OUT” and
“Headphones” options are multiplexed and routed to a single 3.5mm jack on the
board. The default selection is Headphones.
6.1.2.5 Gain
The Gain buttons and drop-box can be used to change the gain of the
headphone amplifier independently of other DAC configuration. Gain
modifications take effect immediately and do not require the sending of an
audio configuration message. Changing the gain causes an
ISC_AUDIO_VOLUME_REQ message to be sent to the target.
The following sequence of messages should be displayed to signal successful
alteration of volume:
‘ISC_AUDIO_VOLUME_REQ: sending’
‘ISC_AUDIO_VOLUME_RESP: success’
The selectable range of values is –18dB to 12dB and the default selection is
0dB. The user interface ignores any commands that would result in the gain
either being decremented beyond its minimum or incremented beyond its
maximum.
