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section 7 - Index of

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;Latest Revision - September 30, 1986movemovemovemovemovemovemovemove#points/2,nO#1,n2#points/4,n6#-1,mOmO,m1mO,m4mO,m5#0,m6;initialize butterflies per group;initialize groups per pass;initialize C pointer <strong>of</strong>fset;initialize A and B address modifiers;for linear addressing;initialize C address modifier for;reverse carry (bit-reversed) addressing;Perform all FFT passes with triple nested DO loopdomovemoveluamoveluamovemovemove#@cvi (@log(points)/@log(2)+0.5),_end-pass#data,rO;initialize A input pointerrO,r4;initialize A output pointer(rO)+nO,r1;initialize B input pointer#coef,r6;initialize C input pointer(r1 )-,r5 ;initialize B output pointernO,n1;initialize pointer <strong>of</strong>fsetsnO,n4nO,n5domovemovemoven2,_end-9rpx:(r1 ),X1x:(r5),ax:(r6)+n6,xOy:(r6),yOy:(rO),b;Iookup -sine and; -cosine values;preload data;update C pointer-_end_bfydomacmacrsublmacmacrsublmovemove_end-9rpmoveIsrlsimove_end-passendmnO,_end_bfyx1,yO,b-xO,y1,bb,a-x1,xO,b-y1,yO,bb,aa,x:(r5)+n5x:(rO)+nO,x1nO,b1b n2,a1a b1,nOa1,n2y:(r1 )+,y1a,x:(r5)+x:(rO),bx:(rO)+,ax:(r1 ),x1b,x:(r4)+y:(rO),ab,y:(r4)a,y:(r5)y:(rO),by:(r1 )+n1 ,y1y:(r4)+n4,y1;Radx20lT;butterfly kernel;update A and B pointers;divide butterflies per group by two;multiply groups per pass by twoFigure B-2 Radix 2, In-Place, Decimatlon-In-Time FFT (Sheet 2 <strong>of</strong> 2)

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