Motorola DSP96002 - Manual (Page 629)

B-110 DSP96002 USER’S MANUAL MOTOROLA
dc 0.0000000E+00
dc 2.000000
dc 3.000000
dc 8.000000
dc 9.000000
dc 12.00000
dc 15.00000
dc 19.00000
dc 20.00000
dc 22.00000
dc 23.00000
dc 24.00000
dc 25.00000
dc 26.00000
dc 27.00000
dc 28.00000
org p:$100
start
move #1,d7.l ;number of groups
move #n/4,d6.l ;number of butterflies/group
move #data,r0 ;upper leg pointer
move #n/2,n0 ;offset between groups
move #n-1,m0 ;mod N
move #data+n/2,r4 ;lower leg pointer
move #n/2,n4 ;offset between groups
do #iord-1,_stage ;do stages
do d7.l,_grp ;do groups
do d6.l,_bfly ;do butterflies
move x:(r0)+,d0.s ;upper leg 1
move x:(r4)+,d1.s ;lower leg 1
faddsub.s d0,d1 x:(r0)-,d2.s ;upper leg 2, point back to 1
move x:(r4)-,d3.s ;lower leg 2, point back to 1
faddsub.s d2,d3 d1.s,x:(r0)+ ;save upper 1, point to 2
move d0.s,x:(r4)+ ;save lower 1, point to 2
move d3.s,x:(r0)+ ;save upper 2, point to next