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Motorola DSP96002 User Manual

Page 545

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B-26

DSP96002 USER’S MANUAL

MOTOROLA

On the delayed LMS algorithm, the coefficients are updated with the error from the previous iteration while

the FIR filter is being computed for the current iteration. In the following implementation, two coefficients

are updated with each pass of the loop.

Delayed LMS Algorithm

iter equ 50 ;Number of LMS iterations

conv_fact equ 0.01 ;Convergence factor

org x:$0

state ds 11 ;State of lms fir

org y:$0

coef ds 10 ;LMS coefficients

e dc 0.0 ;Signal error

xin ds 1 ;Input to system

dsig ds 1 ;Desired signal

org p:$100

lmstest

move #state,r0 ;Set up address generators

move #10,m0

move #xstate,r1

move #9,m1

move #coef,r4

move #9,m4

move #coef,r5

move #9,m5

move #xcoef,r6

move #9,m6

move #iter,d0.l

do d0.l,lms

; LMS algorithm setup

move y:e,d0.s

move #conv_fact,d1.s

fmpy.s d0,d1,d0 y:xin,d6.s

move d0.s,d9.s

move d6.s,x:(r0)

; LMS algorithm loop