Motorola DSP96002 - Manual (Page 641)

B-122 DSP96002 USER’S MANUAL MOTOROLA
move #coef,r4
nop
fclr d1 x:(r0)+,d4.s y:(r4)+,d6.s 1 1
do #nsec,loop 2 3
fmpy d4,d6,d0 fadd.s d1,d2 x:(r0)-,d5.s y:(r4)+,d6.s 1 1
fmpy d5,d6,d1 fadd.s d2,d0 d5.s,x:(r0)+ y:(r4)+,d6.s 1 1
fmpy d6,d4,d1 fadd.s d1,d0 y:(r4)+,d6.s 1 1
fmpy.s d6,d5,d2 d0.s,x:(r0)+ y:(r4)+,d4.s 1 1
fmpy d4,d0,d1 fadd.s d1,d2 x:(r0)+,d4.s y:(r4)+,d6.s 1 1
loop
move d2.s,y:output
--- ---
Totals: 8 5N+4
B.1.51 Four Quadrant Trigonometric SINE (CORDIC Algorithm)
page 132,60,1,1
opt mex,cex
tabsize equ 16
org x:0
scale set 1.0
tantab
tanarg set 45.0*3.14159/180.0
dup tabsize
scale set scale*@cos(tanarg)
dc @tan(tanarg)
tanarg set tanarg/2.0
endm
org p:$100
;
; Do argument reduction, input in d6 in degrees
;
move #-180.0,d7.s ;get range min
fadd.x d7,d6 #1.0/360.0,d5.s ;adjust to min, get range
fmpy.x d5,d6,d6 ;reduce range
floor d6,d5 ;get int part
fsub.x d5,d6 #360.0,d5.s ;get frac part, spread
fmpy.x d5,d6,d6 ;spread fraction part to range
fadd.x d7,d6 ;adjust to min
;
; Input angle in d6 in degrees, -180 < d6 < 180
;
fabs.x d6 d6.s,d3.s ;make positive, save sign