Figure B-2 Lms Adaptive Filter Graphic Representation - Motorola DSP56800 Manual

move
move
move
; save r1, update r1 to point last bi/yi
move
do #n,end_bfly
push x0
mac y0,x0,b
macr -y1,x0,b
move
move
asl a
sub b,a
move
mac y0,x0,b
pop x0
macr y1,x0,b
asl a
sub b,a
end_bfly
move
move
; save r1,
; update r1 to point twiddle factors
;
B.1.7 LMS Adaptive Filter
Figure B-2 gives a graphical representation of this implementation of the LMS adaptive filter.
x(n)
T
c(0)
Figure B-2. LMS Adaptive Filter Graphic Representation
x:(r1)+,y0 x:(r3)+,x0
x:(r0),b
x:(r1)+n,y1
#0,n
x:(r3)+,x0
a,x:(r1)+
x:(r0)+,a
b,x:(r2)+
x:(r0)+n,b
a,x:(r1)+
x:(r0)+,a
x:(r3)+,x0
b,x:(r2)+
x:(r0)+n,b
#xx,n
b,x:(r1)+n
Total:
x(n-1) x(n-K)
T
c(1) c(k)
d(n)
DSP Benchmarks
; y0=wr ; x0=br
;b=ar
; y1=wi
; emulate X:(Rn) adr mode
;2 3
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
;1 1
________
17 13N+9
T
y(n)
e(n)
push br
b=ar+wrbr
b=xr
a=ar
a=2ar-xr=yr
b=ai
b=ai+wrbi
pop br
b=xi ;a=ai
a=2ai-xi=yi
b=ar
save last yi
x(n-N+1)
T
c(N-1)
AA0080
B-7