alc861 Realtek Semiconductor Corporation, alc861 Datasheet - Page 17

• Manufacturer Part Number: alc861
• Description: 7.1 Channel High Definition Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

7.2. Frame Composition
7.2.1.
An outbound frame is composed of one 32-bit command stream and multiple data streams. There are one
or multiple sample blocks in a data stream. Only one sample block exists in a stream if the HDA
controller delivers a 48kHz rate of samples to the codec. Multiple sample blocks in a stream means the
sample rate is a multiple of 48kHz. This means there should be 2 blocks in the same stream to carry
96kHz samples (Figure 6).
For outbound frames, the stream tag is not in SDO, but in the SYNC signal. A new data stream is started
at the end of the stream tag. The stream tag includes a 4-bit preamble and 4-bit stream ID (Figure 7).
To keep the cadence of converters bound to the same stream, samples for these converters must be placed
in the same block.
7.1 Channel High Definition Audio Codec
Controller
HDA
Outbound Frame – Single SDO
SDI14
SDI13
SDO1
SDO0
SYNC
BCLK
RST#
SDI2
SDI1
SDI0
.
.
.
Single SDO
Single SDI
Codec 0
Figure 5.
Two SDOs
Single SDI
Codec 1
Signaling Topology
9
.
.
.
Single SDO
Two SDIs
Codec 2
Track ID: JATR-1076-21
. . .
Multiple SDIs
Codec N
Two SDOs
Datasheet
ALC861
Rev. 1.3