Digital Voice Interface Application Note r0
LE866 DIGITAL VOICE INTERFACE APPLICATION NOTE 80471NT11521A Rev.0 • 2017-01-16 16 of 22
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Normal (I2S) Mode
Module is Master
In this configuration the WAO and CLK signals are generated by the module. The WAO signal defines
the frame of the two audio channels: left and right, refer to fig. 5. The BitClockFrequency (CLK) is
provided by the following expression:
eRateAudioSamplberChannelNumtDataWor dBiequencyBitClockFr
The BitClockFrequency values are shown in Tab. 4.
Tab. 2: BitClockFrequency generated by the module in Master/Normal Mode
Here are the lists of AT commands used to set the module in Master/Normal (I2S) Mode, and
configure the codec in accordance with the module setting. The meanings of the used parameters
values are described after each command
Configure the module in Master/Normal (I2S) Mode (DVI Bus)
AT#DVI=1,2,1
OK
1 enable DVI interface
2 use DVI port 2
1 set the module as Master (factory setting)
Setting for BitClockFrequency = 512 KHz
AT#DVIEXT=1,1,1,0,0
OK
1 Normal Mode
1 sample rate 16 KHz
1 16 bits per sample
0 Mono
0 data is transmitted on the falling edge of clock and sampled on the rising edge
<samplewidth>
DataWordBit
Audio Channels
AudioSampleRate
8 KHz
16 KHz
BitClockFrequency in KHz
0
8
2
128
256
1
16
2
256
512