Motorola DSP96002 User Manual page 716

tst
rts
mszero move
tst
jne
tst
rts
;
; END OF DPLIB
;
end
;
;
; "data" and "coef" are assumed to be in DPLIB format.
; Other variables are assumed to be in IEEE DP format.
;
org
ntaps equ
data ds
coef ds
p ds
a ds
ieee_in ds
ieee_out ds
;
org
start
move
move
move
move
move
move
move
move
_loop
move
move
jsr
do
move
move
jsr
move
move
jsr
move
move
_dpfir
move
jsr
MOTOROLA
d0
x:(r0+ls),d0.l
d0 #0,d2.l
sgntst
d2
Double precision FIR example
x:0
8
4*ntaps
4*ntaps
1
1
1
1
p:$100
#data,r2 ;point to data
#coef,r3 ;point to coefficients
#p,r4 ;temp product
#a,r5 ;product accumulator
#4,n2 ;dp size
n2,n3
#4*ntaps-1,m2 ;mod buffer size
m2,m3
l:ieee_in,d0.d ;get ieee number
r2,r0 ;point r0 to data buffer
ieee2dplib ;convert register to dp and save
#ntaps,_dpfir
r4,r0 ;point to product variable
r3,r1 ;point to coefficients
dp_mpy ;multiply, result in p
r5,r0 ;point to accumulations
r4,r1 ;point to product variable
dp_add ;add them together
(r2)+n2 ;shift to next dp data value
(r3)+n3 ;move to next dp coefficient
r5,r0 ;point to result
dplib2ieee ;convert to a value in d0
DSP96002 USER'S MANUAL
;set the correct flags
;get ls
;check if ls = 0
;if not, check sign
;set the correct flags
B-197