Motorola DSP96002 User Manual page 529

B.1.14 N Cascaded Real Biquad IIR Filters
w(n) = x(n) - a1 * w(n-1) - a2 * w(n-2)
y(n) = w(n) + b1 * w(n-1) + b2 * w(n-2)
X Memory Organization
wN(n-1) Data + 2N-1
wN(n-2)
.
.
w1(n-1)
R1,R0 w1(n-2) Data
move
move
move
move
movep
move
do
mac
macr
mac
mac
end
rnd
movep
B-10
Y Memory Organization
DSP56000 IMPLEMENTATION
#$ffffffff,m0
m0,m4
#data,r0
#coef,r4
x:input,a
x:(r0)+,x0
#n,end
-x0,y0,a x:(r0)-,x1
-x1,y0,a x1,x:(r0)+
x0,y0,a a,x:(r0)+
x1,y0,a x:(r0)+,x0
a
a,x:output
DSP96002 USER'S MANUAL
b1N Coef. + 4N-1
b2N
a1N
a2N
.
.
b11
b21
a11
R4 a21 Coef.
y:(r4)+,y0
y:(r4)+,y0
y:(r4)+,y0
y:(r4)+,y0
y:(r4)+,y0
-------------------
Totals 17
Program ICycles
Words
2 2
1 1
2 2
2 2
1 2
1 1
2 3
1 1
1 1
1 1
1 1
1 1
1 2
4N+16
MOTOROLA