Digital Audio Interface Dai; Table 10: Overview Of Dai Pin Functions; Figure 23: Pcm Interface Application - Siemens TC65 Hardware Interface Description

TC65 Hardware Interface Description
Strictly confidential / Draft
3.13.4

Digital Audio Interface DAI

The DAI can be used to connect audio devices capable of PCM (Pulse Code Modulation), for
example a codec.

Table 10: Overview of DAI pin functions

Signal name on
B2B connector
DAI0
DAI1
DAI2
DAI3
DAI4
DAI5
DAI6
To clock input and output PCM samples the PCM interface delivers a bit clock (BITCLK)
which is synchronous to the GSM system clock. The frequency of the bit clock is 128±1kHz.
The frame sync signal (FS) has a frequency of 8kHz and is high for one BITCLK period. The
PCM interface is master for the bit clock and the frame sync signals.
PCM interface of
the GSM module
BITCLK
TXDAI
RXDAI
TC65_HD_V00.521
Function for PCM Interface
TXDAI
RXDAI
FS (Frame sync)
BITCLK
nc
nc
nc
FS

Figure 23: PCM interface application

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s
Input/Output
O
I
O
O
I
I
I
Codec
bitclk
frame sync
RX_data
TX_data
24.05.2005