alc268 Realtek Semiconductor Corporation, alc268 Datasheet - Page 24

• Manufacturer Part Number: alc268
• Description: 2+2 Channel High Definition Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

7.2.3.
An Inbound Frame – A single SDI is composed of one 36-bit response stream and multiple data streams.
Except for the initialization sequence (turnaround and address frame), SDI is driven by the codec at each
rising edge of BCLK. The controller also samples data at the rising edge of BCLK (Figure 11).
The SDI stream tag is not carried by SYNC, but included in the SDI. A complete SDI data stream
includes one 4-bit stream tag, one 6-bit data length, and n-bit sample blocks. Zeros will be padded if the
total length of the contiguous sample blocks within a given stream is not of integral byte
length (Figure 12).
2+2 Channel High Definition Audio Codec
Previous Frame
BCLK
SYNC
SDI
SDI
Block 1
Frame SYNC
Sample 1 Sample 2
Inbound Frame – Single SDI
B
Stream Tag
9
Response Stream
Stream Tag
msb
B
Block 2
A 48kHz Frame is Composed of a Response Stream and Multiple Data streams
8
...
B
7
lsb
B
Sample Block(s)
6
...
...
B
msb first in a sample
5
Data Length in Bytes
Figure 12. SDI Stream Tag and Data
Block Y
B
Figure 11. SDI Inbound Stream
Sample Z
4
B
Stream 'A'
3
A Complete Stream
Null Pad
B
Z channels of PCM Sample
2
B
1
16
For 48kHz rate, only Block1 is included
For 96kHz rate, Block{1, 2} includes {(N)
B
0
D
n-Bit Sample Block
n-1
(Data Length in Bytes *8)-Bit
D
n-2
Stream 'X'
D
0
Null Field
Track ID: JATR-1076-21
0
Null Pad
0
0s
Padded at the end of Frame
th
0
(N+1)
Next Frame
ALC268 Series
0
th
} time of samples
Datasheet
Next Stream
Rev. 1.3