alc885-gr Realtek Semiconductor Corporation, alc885-gr Datasheet - Page 18

• Manufacturer Part Number: alc885-gr
• Description: 7.1+2 Channel High-performance Hda Codec With Content Protection
• Manufacturer: Realtek Semiconductor Corporation

7.1.1.
7.1+2 Channel High-Performance HDA Codec
With Content Protection
Item
BCLK
SYNC
SDO
SDI
RST#
Signal Name
BCLK
SYNC
SDO
SDI
RST#
BCLK
SYNC
SDO
SDI
Signal Definitions
Description
24.0MHz bit clock sourced from the HDA controller and connecting to all codecs
48kHz signal used to synchronize input and output streams on the link. It is sourced from the HDA
controller and connects to all codecs
Serial data output signal driven by the HDA controller to all codecs. Commands and data streams are carried
on SDO. The data rate is double pumped; the controller drives data onto the SDO, the codec samples data
present on SDO with respect to each edge of BCLK. The HDA controller must support at least one SDO. To
extend outbound bandwidth, multiple SDOs may be supported
Serial data input signal driven by the codec. This is point-to-point serial data from the codec to the HDA
controller. The controller must support at least one SDI, and up to a maximum of 15 SDI’s can be supported.
SDI is driven by the codec at each rising edge of BCLK, and sampled by the controller at each rising edge of
BCLK. SDI can be driven by the controller to initialize the codec’s ID
Active low reset signal. Asserted to reset the codec to default power on state. RST# is sourced from the
HDA controller and connects to all codecs
Codec/Controller
Controller
Controller
Controller
Controller
Source
Controller samples SDI at rising edge of BCLK
Type for Controller Description
Input/Output
Codec samples SDO at both rising and falling edge of BCLK
Table 6.
Table 5.
Output
Output
Output
Output
8-Bit Frame SYNC
7
3
6
Figure 5.
5
2
4
HDA Signal Definitions
Link Signal Definitions
3
1
2
Global 24.0MHz bit clock
Global 48kHz Frame Sync and outbound tag signal
Serial data output from the controller
Serial data input from codec. Weakly pulled down by the
controller
Global active low reset signal
10
1
0
Bit Timing
0
999 998 997 996 995 994 993 992 991 990
499
Start of Frame
498
497
496
495
494
ALC885 Series
Datasheet
Rev. 1.1