AD1986A_15 Datasheet, PDF (37/56 Pages) Analog Devices – AC 97 and HD Audio SoundMAX Codec

AD1986A
EQ CONTROL REGISTER (REGISTER 0x60)
Register 0x60 is a read/write register that controls equalizer function and data setup. The register also contains the biquad and coefficient
address pointer, which is used in conjunction with the EQ data register (0x78) to set up the equalizer coefficients. The reset default
disables the equalizer function until the coefficients can be properly set up by the software and sets the symmetry bit to allow equal
coefficients for left and right channels.
Reg Name D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Default
0x60 EQ
EQM x x x x x x x SYM CHS BCA5 BCA4 BCA3 BCA2 BCA1 BCA0 0x8080
Control
Table 99. Biquad and Coefficient Address Pointer
BCA [5,0] Biquad 0 Coef a0 BCA [5,0] = 011011
Biquad 0 Coef a1 BCA [5,0] = 011010
Biquad 0 Coef a2 BCA [5,0] = 011001
Biquad 0 Coef b1 BCA [5,0] = 011101
Biquad 0 Coef b2 BCA [5,0] = 011100
Biquad 1
Biquad 1
Biquad 1
Biquad 1
Biquad 1
Coef a0
Coef a1
Coef a2
Coef b1
Coef b2
BCA [5,0] = 100000
BCA [5,0] = 011111
BCA [5,0] = 011110
BCA [5,0] = 100010
BCA [5,0] = 100001
Biquad 2
Biquad 2
Biquad 2
Biquad 2
Biquad 2
Coef a0
Coef a1
Coef a2
Coef b1
Coef b2
BCA [5,0] = 100101
BCA [5,0] = 100100
BCA [5,0] = 100011
BCA [5,0] = 100111
BCA [5,0] = 100110
Biquad 3
Biquad 3
Biquad 3
Coef a0
Coef a1
Coef a2
BCA [5,0] = 101010
BCA [5,0] = 101001
BCA [5,0] = 101000
Biquad 3
Biquad 3
Biquad 4
Biquad 4
Biquad 4
Biquad 4
Biquad 4
Biquad 5
Biquad 5
Biquad 5
Biquad 5
Biquad 5
Biquad 6
Biquad 6
Biquad 6
Biquad 6
Biquad 6
Coef b1
Coef b2
Coef a0
Coef a1
Coef a2
Coef b1
Coef b2
Coef a0
Coef a1
Coef a2
Coef b1
Coef b2
Coef a0
Coef a1
Coef a2
Coef b1
Coef b2
BCA [5,0] = 101100
BCA [5,0] = 101011
BCA [5,0] = 101111
BCA [5,0] = 101110
BCA [5,0] = 101101
BCA [5,0] = 110001
BCA [5,0] = 110000
BCA [5,0] = 110100
BCA [5,0] = 110011
BCA [5,0] = 110010
BCA [5,0] = 110110
BCA [5,0] = 110101
BCA [5,0] = 111001
BCA [5,0] = 111000
BCA [5,0] = 110111
BCA [5,0] = 111011
BCA [5,0] = 111010
Table 100.
Register
CHS
(Channel
Select)
SYM
(Symmetry)
EQM
(Equalizer
Mute)
x
Function
Swaps the blocks that are used for symmetry coefficients. Only valid when the SYM bit is set.
CHS
Function
Default
0
Selects left channel coefficients’ data block
Default
1
Selects right channel coefficients’ data block
When set to 1 this bit indicates that the left and right channel coefficients are equal.
This shortens the coefficients setup sequence since only the left channel coefficients need to be addressed and set up. The
right channel coefficients are simultaneously copied into memory.
SYM
Function
0
Left and right channels can use different coefficients
1
Indicates that the left and right channel coefficients are equal
Default
When set to 1, this bit disables the equalizer function (allows all data to pass through). The reset default sets this bit to 1,
disabling the equalizer function until the biquad coefficients can be properly set.
EQM
Function
0
EQ is enabled.
1
EQ is disabled. Data will pass-through without change.
Default
Reserved.
Default: 0
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