Motorola DSP56156 Manual page 172

If a unity gain is expected from the A/D section, the gain of that filter has to be multiplied
by 1/1.0137 in order to compensate the attenuation of the comb filter at the given decima-
tion ratio (refer to Table 6-20).
Table 6-21 Coefficient of the Filter Shown in Figure 6-35
; Source filter file: "compad81.IIR.Filter"
_filter_type
_NSTAGES
Figure 6-36 shows the overall response of the A/D section cascaded with the DSP IIR filter
described above.
MOTOROLA
APPLICATION EXAMPLES
equ BIQUAD_FILTER_TYPE
equ 5
dc $000d
; Biquad stage no. 1
dc $d344
dc $5c11
dc $0032
dc $1ca7
; Biquad stage no. 2
dc $cc88
dc $531c
dc $fe28
dc $191c
; Biquad stage no. 3
dc $d248
dc $691f
dc $f9a7
dc $12b0
; Biquad stage no. 4
dc $c704
dc $4c31
dc $e31d
dc $de6a
; Biquad stage no. 5
dc $c3c1
dc $7bed
dc $d103
dc $ef0b
DSP56156 ON-CHIP SIGMA/DELTA CODEC
; number of biquadratic stages
; g = 0.0007686455615/2
; -d2_1 = -0.6989950203/2
; -d1_1 = 1.438546964/2
; n2_1 = 0.003056686097/2
; n1_1 = 0.4476798556/2
; -d2_2 = -0.8042193348/2
; -d1_2 = 1.298599572/2
; n2_2 = -0.02879117954/2
; n1_2 = 0.3923349351/2
; -d2_3 = -0.7143639147/2
; -d1_3 = 1.64250833/2
; n2_3 = -0.09919829751/2
; n1_3 = 0.2920120584/2
; -d2_4 = -0.8904019637/2
; -d1_4 = 1.190507817/2
; n2_4 = -0.4513353886/2
; n1_4 = -0.5247662529/2
; -d2_5 = -0.9413669532/2
; -d1_5 = 1.936312495/2
; n2_5 = -0.7341826041/2
; n1_5 = -0.2649274056/2
6 - 57