alc658 Realtek Semiconductor Corporation, alc658 Datasheet - Page 45

• Manufacturer Part Number: alc658
• Description: Six-channel Ac?97 2.3 Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

9.
9.1. Clocking
The clock source is decided by XTLSEL latched from pin-46 after power-on reset. The clock source of different
configurations is listed below:
de-asserted, the ALC658 is a consumer of BITCLK. The ALC658 uses external 12.288MHz BITCLK as its clock source.
9.2. AC-Link
When the ALC658 receives serial data from the AC97 controller, it samples SDATA_OUT on the falling edge of BIT_CLK.
When the ALC658 sends serial data to the AC97 controller, it starts to drive SDATA_IN on the rising edge of BIT_CLK.
The ALC658 will return any uninstalled bits or registers with 0 for read operations. The ALC658 also stuffs the
unimplemented slot or bit with 0’s in SDATA_IN. Note that AC-LINK is MSB-justified.
Refer to “Audio CODEC ’97 Component Specification Revision 2.3.” for details.
Default ALC658 Slot Arrangement – CODEC ID = 00 (the ALC658 supports primary mode only)
Six-Channel AC’97 2.3 Audio Codec
***According to AC’97 ver 2.3, in Primary Mode, if a clock is present at BIT-CLK pin for at least 5 cycles before RESET# is
**Low: Pulled low by a 0 ohm resistor. NC: Not Connected or pulled high.
SYNC
SDATA-
OUT
SDATA-IN
*Pin-46 is internally pulled high by a weak resistor.
Pin-46 (XTLSEL)*
NC
Low**
NC
Slot#
Configuration
Design and Layout Guide
TAG
TAG
0
ADD
CMD
1
0 (Primary)
0 (Primary)
0 (Primary)
DATA
DATA
ID0
2
PCM
PCM
L
L
3
Output 12.288MHz
Output 12.288MHz
PCM
PCM
R
R
BIT-CLK
Table 64. Clocking
4
Table 65. AC-Link
Input
5
41
Operation & ID0
CEN
6
Clock Source
Crystal or ext. 24.576MHz is attached at XTL-IN
Crystal or ext. 14.318MHz is attached at XTL-IN
12.288M input at BIT-CLK***
SURR
L
7
SURR
R
8
LFE
9
S/PDIF
10
L
S/PDIF
Datasheet
11
L
ALC658
Rev. 1.3
12