ALC883 datasheet(21/78 Pages) REALTEK

21 / 78 page

ALC883 Series

Datasheet

7.1+2 Channel High Definition Audio Codec

Track ID: JATR-1076-21

Rev. 1.3

7.2.2.

Outbound Frame – Multiple SDOs

The HDA controller allows two SDO signals to be used to strip outbound data, completing transmission

in less time to get more bandwidth. If software determines the target codec supports multiple SDO

capability, it enables the ‘Strip Control’ bit in the controller’s Output Stream Control Register to initiate a

specific stream (Stream ‘A’ in Figure 9) to be transmitted on multiple SDOs. In this case, the MSB of

stream data is always carried on SDO0, the second bit on SDO1 and so forth.

SDO1 is for transmitting a stripped stream. The codec does not support multiple SDOs connected to

SDO0.

To guarantee all codecs can determine their corresponding stream, the command stream is not stripped. It

is always transmitted on SDO0, and copied on SDO1.

Command Stream

SDO

SYNC

Stream 'X' to Codec X

Stream 'A' Tag

Stream 'X' Tag

Frame SYNC

SDO

. . .

n-1

Dn-2

n-3

. . .

Stream 'Y' to Codec Y

Stream 'Y' Tag

Stream 'A' to Codec A

Stream A is "bit-stripped" on SDO0 and SDO1

Command Stream

Command Stream is unchanged, not stripped

Figure 9.

Stripped Stream on Multiple SDOs

ALC883 Datasheet(PDF) 21 Page - Realtek Semiconductor Corp.