Digital Voice Interface Application Note r0

LE866 DIGITAL VOICE INTERFACE APPLICATION NOTE 80471NT11521A Rev.0 • 2017-01-16 11 of 22
Reproduction forbidden without Telit Communications S.p.A. written authorization – All Rights Reserved
4 DVI BUS
DVI PIN LIST
The physical DVI interface provided by the Telit’s modules is based on the standard I2S Bus.
An overview of the standard I2S Bus is described in chapter 6.1.
The following Table summarizes the DVI signals and a short description for each one of them; refer to
Telit Hardware User Guide, in accordance with the used module, to have information on electrical
characteristics and signals pin-out.
The figures below show the two configurations of the DVI interface relating to the Word Alignment and
Clock signals. When the module is Master the Clock and Word Alignment signals (also called Word
Alignment Output WAO) are generated by the module itself, otherwise, when it is Slave, both signals
are generated by the connected Audio Device Codec.
In general, before establishing a voice call it is possible to select one of the two configurations and in
accordance with the selected setting, configure the module and the codec via the AT commands
described in At User Guide.
The next pages describe the use of these AT commands.
fig. 2: Master and Slave Configurations
Signal
Function
Description
DVI_CLK
Clock
Data Clock
DVI_WAO
Word Alignment
Frame Synchronism
DVI_RX
Serial audio data input
Received Data
DVI_TX
Serial audio data output
Transmitted Data