Other Parts Discussed in Thread: TAS5782M
Hi,
I am using TAS5766M and PPC3 for Mono Speaker System.
My customer wants to control EQ in their program, so I have to provide TA5766M EQ API.
So I need EQ control information.
For example, when EQ4 is enabled, I2C Monitor shows as follows.
// EQ4 on: volume -12dB
w 98 00 00
r 98 76 01
w 98 00 00
r 98 76 01
w 98 00 00
r 98 76 01
w 98 00 32
w 98 8c 7f ff ff 00 d9 29 1c 00 4a fc 10 00 2b 50 50 00 9d a1 af 00 // BQ coefficients
w 98 00 33
w 98 d0 23 c3 59 00 // Gain Scaling?
w 98 00 2c
w 98 88 10 1d 3f 00 // Volume?
w 98 00 2c
w 98 01 05
w 98 00 32
w 98 8c 7f ff ff 00 d9 29 1c 00 4a fc 10 00 2b 50 50 00 9d a1 af 00
w 98 00 33
w 98 d0 23 c3 59 00
w 98 00 2c
w 98 88 10 1d 3f 00
EQ4 coefficients address seems to start at (Page 0x32/Register 0x8c).
Gain scaling and Volume(?) seems to be at (Page 0x33/Register 0xd0) and (Page 0x2c/Register 0x88).
BQ coefficients seems as follows (from TAS5782M Process Flows document).
H(z) = (b0 + b1*z^-1 + b2*z^-2) / (1 + a1*z^-1 + a2*z^-2) // (a0=1)
{ b0, b1/2, b2, -a1/2, -a2 } // 24b_coeff + 8b_zero
Any BQ with coefficients greater than 1 undergoes gain scaling
EQ coefficients addresses may be inferred from I2C Monitor.
All BQ gain scalings are combined to one register? (Page 0x33/Register 0xd0)
Please, let me know Gain/Volume calculation [(Page 0x33/Register 0xd0) and (Page 0x2c/Register 0x88)]
and other EQ control information which I should know.
Best regards,
Kee