cs5535 National Semiconductor Corporation, cs5535 Datasheet - Page 239

• Manufacturer Part Number: cs5535
• Description: Geode Cs5535 Companion Multi-function South Bridge
• Manufacturer: National Semiconductor Corporation

Revision 0.8
ACC Register Descriptions
5.3.2.4
ACC I/O Offset
Type
Reset Value
Note: Since this register could potentially be accessed by both an audio driver and a modem driver running at the same
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
30:24
23:22
15:0
Bit
Bit
17
16
31
time, it is expected that all writes occur as atomic read-modify-write accesses.
Codec Control Register (ACC_CODEC_CNTL)
CMD_ADD
Name
STS_NEW
RSVD
STS_DATA
Name
RW_CMD
CMD_ADD
COMM_SEL
0Ch
R/W
00000000h
ACC_CODEC_STATUS Bit Descriptions (Continued)
COMM
_SEL
Description
Codec Status New (Read to Clear). Indicates if the status data in bits [15:0] is new:
0: Not new.
1: New.
This bit is set by hardware after receiving valid codec status data in slot 2 of the input
stream. Upon issuing a read to the codec registers, software should wait for this flag to
indicate that the corresponding data has been returned.
Reserved. Reads return 0.
Codec Status Data (Read Only). This is the codec status data that is received from
the codec in slot 2, bits [19:4] of the serial input stream. This is used for reading the
contents of registers inside the AC97 codec.
Description
Codec Read/Write Command. This bit specifies a read or write operation targeting the
AC97 codec’s registers.
0: Write.
1: Read.
This bit determines whether slot 1, bit 19 of the serial output stream will be high or low.
Codec Command Address. Address of the codec control register for which the com-
mand is being sent. This address goes in slot 1, bits [18:12] of the serial output stream.
This is used for specifying the address of a register in the AC97 codec (for reading or
writing).
Audio Codec Communication. Selects which codec to communicate with (for register
reads/writes):
00: Codec 1 (Primary)
01: Codec 2 (Secondary)
10: Codec 3
11: Codec 4
These bits determine output slot 0, bits [1:0]. When these bits are non-zero, bits [14:13]
of output slot 0 must be set to zeros regardless of the validity of slot 1 and slot 2.
(Continued)
ACC_CODEC_CNTL Bit Descriptions
ACC_CODEC_CNTL Register Map
239
9
CMD_DATA
8
7
6
5
4
3
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2
1
0