Motorola DSP96002 User Manual page 632

move
_firststage
nop
nop
move
move
move
move
move
move
move
do
move
do
move
do
move
move
faddsub.s d0,d1
faddsub.s d4,d5
faddsub.s d2,d3
faddsub.s d6,d7
move
move
_bfly
move
_grps
move
lsr
move
move
lsl
move
lea
MOTOROLA
d2.s,y:(r0)+
#data,r0
#n/2-1,m0
#n/4,n0
#data+n/4,r4
#n/4,n4
#1,d8.l
#n/8,d9.l
#iord-2,_mid
d8.l,d7.l
d7.l,_grps
d9.l,d7.l
d7.l,_bfly
x:(r0)+,d0.s
x:(r4)+,d1.s
x:(r0)-,d2.s
x:(r4)-,d3.s
d1.s,x:(r0)+
d0.s,x:(r4)+
d3.s,x:(r0)+
d2.s,x:(r4)+
x:(r0)+n0,d0.s y:(r4)+n4,d1.s
d9.l,d7.l
d7 d7.l,n0 ;divide # bflys by 2, divide offset by 2
d7.l,d9.l
d8.l,d6.l
d6 n0,n4
d6.l,d8.l
(r0)+n0,r4
DSP96002 USER'S MANUAL
;save dif 2
;point to data
;mod n/2
;offset to next group
;point to lower leg of half
;offset to next group
;number of groups/stage
;number of bflys/group
;do middle part of transform
;get group count
;do groups
;get bfly count
;do bflys
y:,d4.s ;upper x,y #1
y:,d5.s ;lower x,y #1
y:,d6.s ;upper x,y #2
y:,d7.s ;lower x,y #2
d5.s,y: ;save sum x,y #1
d4.s,y: ;save dif x,y #1
d7.s,y: ;save sum x,y #2
d6.s,y: ;save dif x,y #2
;adj r0,r4
;get # bflys/stage
;save # bflys/stage
;get # of groups/stage
;multiply # groups by 2,copy offset
;save new # groups/stage
;update other pointer
B-113