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hellwig |
% the bit-reversal portion of a 256-point Fast Fourier Transform
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t IS $255
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n IS 256
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pi GREG
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pj GREG
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tx GREG
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i GREG
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j GREG
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LOC Data_Segment
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Data GREG @
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% Here follows 256 octabyte pairs for (real,imag) parts of complex data
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% I'm faking it with small integer numbers just for easy testing
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% But it uses long lines, so assemble with "mmixal -b 80"
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OCTA 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
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OCTA 16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31
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OCTA 32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47
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OCTA 48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63
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OCTA 64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79
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OCTA 80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95
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OCTA 96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111
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OCTA 112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127
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OCTA 128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143
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OCTA 144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159
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OCTA 160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175
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OCTA 176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191
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OCTA 192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207
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OCTA 208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223
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OCTA 224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239
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OCTA 240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255
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OCTA 256,257,258,259,260,261,262,263,264,265,266,267,268,269,270,271
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OCTA 272,273,274,275,276,277,278,279,280,281,282,283,284,285,286,287
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OCTA 288,289,290,291,292,293,294,295,296,297,298,299,300,301,302,303
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OCTA 304,305,306,307,308,309,310,311,312,313,314,315,316,317,318,319
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OCTA 320,321,322,323,324,325,326,327,328,329,330,331,332,333,334,335
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OCTA 336,337,338,339,340,341,342,343,344,345,346,347,348,349,350,351
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OCTA 352,353,354,355,356,357,358,359,360,361,362,363,364,365,366,367
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OCTA 368,369,370,371,372,373,374,375,376,377,378,379,380,381,382,383
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OCTA 384,385,386,387,388,389,390,391,392,393,394,395,396,397,398,399
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OCTA 400,401,402,403,404,405,406,407,408,409,410,411,412,413,414,415
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OCTA 416,417,418,419,420,421,422,423,424,425,426,427,428,429,430,431
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OCTA 432,433,434,435,436,437,438,439,440,441,442,443,444,445,446,447
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OCTA 448,449,450,451,452,453,454,455,456,457,458,459,460,461,462,463
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OCTA 464,465,466,467,468,469,470,471,472,473,474,475,476,477,478,479
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OCTA 480,481,482,483,484,485,486,487,488,489,490,491,492,493,494,495
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OCTA 496,497,498,499,500,501,502,503,504,505,506,507,508,509,510,511
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LOC #100
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Main SET i,n-1
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0H GREG #0102040810204080
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1H MOR j,0B,i
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CMP t,i,j
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PBNN t,2F jump if i<=j
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16ADDU pi,i,Data pi=&Data[i]
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16ADDU pj,j,Data pj=&Data[j]
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LDO t,pi,0
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LDO tx,pj,0
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STO t,pj,0 swap Data[i].real with Data[j].real
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STO tx,pi,0
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LDO t,pi,8
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LDO tx,pj,8
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STO t,pj,8 swap Data[i].imag with Data[j].imag
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STO tx,pi,8
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2H SUB i,i,1 i--
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PBP i,1B repeat until i==0
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TRAP 0,Halt,0
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