ad1881a Analog Devices, Inc., ad1881a Datasheet - Page 19

• Manufacturer Part Number: ad1881a
• Description: Ac?97 Soundmax Codec
• Manufacturer: Analog Devices, Inc.

Miscellaneous Control Bits (Index 76h)
ARSR
DRSR
SRX8D7
SRX10D7
MODEN
ALSR
DLSR
DMS
DAM
LPMIX
DACZ
Sample Rate 0 (Index 78h)
Note: 32h is an alias for 78h. The VRA bit in register 2Ah must be set for the alias to work; if a zero is written to VRA then both
sample rates are reset to 48k.
SR0[15:0]
R g
R g
R g
R g
R
N m
N m
N m
N m
N
8 7 h
8 7 h
8 7 h
8 7 h
8 7
R g
R g
R g
N m
N m
N m
6 7 h
6 7 h
6 7 h
R g
R
N m
N
6 7 h
6 7
e
e
e
e
e
u
u
u
u
u
e
e
e
e
e
u
u
u
u
u
h
h
g
g
m
m
N
N
N
N
N
S
S
S
S
S
N
N
N
N
N
M
M
M
M
M
a
a
a
a
a
a
a
a
a
a
a
a
a
a
a
m
m
m
m
m
i
i
i
i
i
m
m
m
m
m
m
m
m
m
m
c s
c s
c s
c s
c s
p
p
p
p
p
e
e
e
e
e
e
e
e
e
e
C
C
C
e l
e l
e l
e l
e l
C
C
o
o
o
o
o
R
R
R
R
R
n
n
n
n
n
a
a
a
r t
r t
r t
r t
r t
a
a
e t
e t
e t
e t
e t
l o
l o
l o
l o
l o
0
0
0
ADC right sample generator select
DAC right sample generator select
Multiply SR1 rate by 8/7.
Multiply SR1 rate by 10/7. SRX10D7 and SRX8D7 are mutually exclusive; SRX10D7 has priority if both are set.
Modem filter enable (left channel only). Change only when DACs are powered down.
ADC left sample generator select
DAC left sample generator select
Digital Mono Select.
Digital Audio Mode. DAC Outputs bypass analog mixer and sent directly to the codec output.
Low Power Mixer. Keeps CD to LINE_OUT alive for notebook applications.
Zero fill (vs. repeat) if DAC is starved for data.
0
0
in 1 Hertz increments. Programming a value greater than 48 kHz or less than 7 kHz may cause unpredictable results.
Writing to this register allows the user to program the sampling frequency from 7 kHz (1B58h) to 48 kHz (BB80h)
B
B
B
B
B
i
i
i
i
i
0 = SR0 Selected (32h)
1 = SR1 Selected (2Ch).
0 = SR0 Selected (32h)
1 = SR1 Selected (2Ch).
0 = SR0 Selected (32h)
1 = SR1 Selected (2Ch).
0 = SR0 Selected (32h)
1 = SR1 Selected (2Ch).
0 = Mixer
1 = Left DAC and Right DAC.
s t
s t
s t
s t
s t
D 5 1
D 5 1
D 5 1
D 5 1
D
S
S
S
S
S
R
R
R
R
R
5 1
0
0
0
0
0
5 1
5 1
5 1
5 1
5 1
D 5 1
D 5 1
D 5 1
D 5 1
D
D C
D C
D C
D C
D
Z Z Z Z Z
5 1
A
A
A
A
A
C
D 4 1
D 4 1
D 4 1
D 4 1
D
S
S
S
S
S
R
R
R
R
R
4 1
0
0
0
0
0
D 4 1
D 4 1
D 4 1
D 4 1
D
L
L
L
L
L
X X X X X
4 1
4 1
4 1
4 1
4 1
P
P
P
P
P
4 1
M
M
M
M
M
D 3 1
D 3 1
D 3 1
D 3 1
D
S
S
S
S
S
I
I
I
I
I
R
R
R
R
R
3 1
0
0
0
0
0
D 3 1
D 3 1
D 3 1
D 3 1
D
X X X X X
3 1
3 1
3 1
3 1
3 1
3 1
D 2 1
D 2 1
D 2 1
D 2 1
D
S
S
S
S
S
D 2 1
D 2 1
D 2 1
D M
D M
D M
D 2 1
D
D M
D
R
R
R
R
R
2 1
A
A
A
2 1
A
A
0
0
0
0
0
2 1
2 1
2 1
2 1
2 1
M
D 1 1
D 1 1
D 1 1
D 1 1
D
S
S
S
S
S
D 1 1
D 1 1
D 1 1
D 1 1
D
D S
D S
D S
D S
D
R
R
R
R
R
M
M
M
1 1
1 1
M
M
0
0
0
0
0
S
1 1
1 1
1 1
1 1
1 1
D 0 1
D 0 1
D 0 1
D 0 1
D
D
D
D
D
D
D 0 1
D 0 1
D 0 1
D 0 1
D
S
S
S
S
S
0 1
L
L
L
L
L
R
R
R
R
R
0 1
S
S
S
S
S
0
0
0
0
0
R
R
R
R
R
0 1
0 1
0 1
0 1
0 1
D9
D9
D9
D9
D
X X X X X
D9
D9
D9
D9
D
S
S
S
S
S
9
R
R
R
R
R
9
9 0
9 0
9 0
9 0
9 0
D8
D8
D8
A
A
A
D8
D
A
A
L
L
L
L
L
8
D8
D8
D8
S
S
S
D8
D
S
S
S
S
S
S
S
R
R
R
R
R
R
R
R
R
R
8
8 0
8 0
8 0
8 0
8 0
D7
D7
D7
D7
D
M D
M D
M D
M D
M
EN
EN
EN
E
EN
N
7
D7
D7
D7
D7
D
S
S
S
S
S
O
O
O
O
O
R
R
R
R
R
7
D
7 0
7 0
7 0
7 0
7 0
D6
D6
D6
D6
D
S
S
S
S
S
D7
D7
D7
D
D7
D6
D6
D6
D6
D
S
S
S
S
S
R
R
R
R
R
6
7
R
R
R
R
R
X
X
X
X
X
6
6 0
6 0
6 0
6 0
6 0
0 1
0 1
0 1
0 1
0 1
D5
D5
D5
S
S
S
D5
D
S
S
D5
D5
D5
D5
D
S
S
S
S
S
D7
D7
D7
D
D7
R
R
R
R
R
R
R
R
R
R
5
5
7
5 0
5 0
5 0
5 0
5 0
X
X
X
X
X
8
8
8
8
8
D4
D4
D4
D4
D
S
S
S
S
S
R
R
R
D4
D4
D4
D4
D
X X X X X
R
R
4
4 0
4 0
4 0
4 0
4 0
4
D3
D3
D3
D3
D
X X X X X
D
S
3
R
3
3 0
D2
D2
D2
D2
D
D
D
D
D
D
2
R
R
R
R
R
D2
D2
D2
D2
D
S
S
S
S
S
S
S
S
S
S
R
R
R
R
R
2
R
R
R
R
R
2 0
2 0
2 0
2 0
2 0
D1
D1
D1
D1
D
X X X X X
D1
D1
D1
S
S
S
D1
D
S
S
1
R
R
R
R
R
AD1881A
1
1 0
1 0
1 0
1 0
1 0
D0
D0
D0
D0
D
A
A
A
A
A
R
R
R
R
R
0
D0
D0
D0
D0
D
S
S
S
S
S
S
S
S
S
S
R
R
R
R
R
R
R
R
R
R
0
0 0
0 0
0 0
0 0
0 0
D
D
D
4 0 h
4 0 h
4 0
D
D
4 0 h
4 0
D
D
D
D
D
B
B
B
B
B
e
e
e
e
e
4 0
4 0
4 0
4 0
4 0
a f
a f
a f
a f
a f
B
B
B
e
e
e
B
B
e
e
h
h
u
u
u
a f
a f
a f
a f
a f
u
u
0 8
0 8
0 8
0 8
0 8
t l
t l
t l
t l
t l
u
u
u
u
u
H
H
H
H
H
t l
t l
t l
t l
t l