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Appendix b:

c_fft_given.asm

1 ; v:\ece420\54x\dspclib\c_fft_given.asm 2 ; dgs - 9/14/2001 3 .copy "v:\ece420\54x\dspclib\core.inc" 4 5 .global _bit_rev_data 6 .global _fft_data 7 .global _window 8 9 .global _bit_rev_fft 10 11 .sect ".data" 12 13 .align 4*N 14 _bit_rev_data .space 16*2*N ; Input to _bit_rev_fft 15 16 .align 4*N 17 _fft_data .space 16*2*N ; FFT output buffer 18 19 20 ; Copy in the Hamming window 21 _window ; The Hamming window 22 .copy "window.asm" 23 24 .sect ".text" 25 26 _bit_rev_fft 27 ENTER_ASM 28 29 call bit_rev ; Do the bit-reversal. 30 31 call fft ; Do the FFT 32 33 LEAVE_ASM 34 RET 35 36 bit_rev: 37 STM #_bit_rev_data,AR3 ; AR3 -> original input 38 STM #_fft_data,AR7 ; AR7 -> data processing buffer 39 MVMM AR7,AR2 ; AR2 -> bit-reversed data 40 STM #K_FFT_SIZE-1,BRC 41 RPTBD bit_rev_end-1 42 STM #K_FFT_SIZE,AR0 ; AR0 = 1/2 size of circ buffer 43 MVDD *AR3+,*AR2+ 44 MVDD *AR3-,*AR2+ 45 MAR *AR3+0B 46 bit_rev_end: 47 NOP 48 RET 49 50 ; Copy the actual FFT subroutine. 51 fft_data .set _fft_data ; FFT code needs this. 52 .copy "v:\ece420\54x\dsplib\fft.asm" 53 54 55 ; If you need any more assembly subroutines, make sure you name them 56 ; _name, and include a ".global _name" directive at the top. Also, 57 ; don't forget to use ENTER_ASM at the beginning, and LEAVE_ASM 58 ; and RET at the end!

Appendix c:

lab4.h

1 #define N 1024 /* Number of FFT points */ 2 #define logN 10

lab4fft.c

1 /*****************************************************************/ 2 /* lab4fft.c */ 3 /* Douglas L. Jones */ 4 /* University of Illinois at Urbana-Champaign */ 5 /* January 19, 1992 */ 6 /* Changed for use w/ short integers and lookup table for ECE420 */ 7 /* Matt Kleffner */ 8 /* February 10, 2004 */ 9 /* */ 10 /* fft: in-place radix-2 DIT DFT of a complex input */ 11 /* */ 12 /* Permission to copy and use this program is granted */ 13 /* as long as this header is included. */ 14 /* */ 15 /* WARNING: */ 16 /* This file is intended for educational use only, since most */ 17 /* manufacturers provide hand-tuned libraries which typically */ 18 /* include the fastest fft routine for their DSP/processor */ 19 /* architectures. High-quality, open-source fft routines */ 20 /* written in C (and included in MATLAB) can be found at */ 21 /* http://www.fftw.org */ 22 /* */ 23 /* #defines expected in lab4.h */ 24 /* N: length of FFT: must be a power of two */ 25 /* logN: N = 2**logN */ 26 /* */ 27 /* 16-bit-limited input/output (must be defined elsewhere) */ 28 /* real: integer array of length N with real part of data */ 29 /* imag: integer array of length N with imag part of data */ 30 /* */ 31 /* sinetables.h must */ 32 /* 1) #define Nt to an equal or greater power of two than N */ 33 /* 2) contain the following integer arrays with */ 34 /* element magnitudes bounded by M = 2**15-1: */ 35 /* costable: M*cos(-2*pi*n/Nt), n=0,1,...,Nt/2-1 */ 36 /* sintable: M*sin(-2*pi*n/Nt), n=0,1,...,Nt/2-1 */ 37 /* */ 38 /*****************************************************************/ 39 40 #include "lab4.h" 41 #include "sinetables.h" 42 43 extern int real[N]; 44 extern int imag[N]; 45 46 void fft(void) 47 { 48 int i,j,k,n1,n2,n3; 49 int c,s,a,t,Wr,Wi; 50 51 j = 0; /* bit-reverse */ 52 n2 = N >> 1; 53 for (i=1; i < N - 1; i++) 54 { 55 n1 = n2; 56 while ( j >= n1 ) 57 { 58 j = j - n1; 59 n1 = n1 >> 1; 60 } 61 j = j + n1; 62 63 if (i < j) 64 { 65 t = real[i]; 66 real[i] = real[j]; 67 real[j] = t; 68 t = imag[i]; 69 imag[i] = imag[j]; 70 imag[j] = t; 71 } 72 } 73 74 /* FFT */ 75 n2 = 1; n3 = Nt; 76 77 for (i=0; i < logN; i++) 78 { 79 n1 = n2; /* n1 = 2**i */ 80 n2 = n2 + n2; /* n2 = 2**(i+1) */ 81 n3 = n3 >> 1; /* cos/sin arg of -6.283185307179586/n2 */ 82 a = 0; 83 84 for (j=0; j < n1; j++) 85 { 86 c = costable[a]; 87 s = sintable[a]; 88 a = a + n3; 89 90 for (k=j; k < N; k=k+n2) 91 { 92 /* Code for standard 32-bit hardware, */ 93 /* with real,imag limited to 16 bits */ 94 /* 95 Wr = (c*real[k+n1] - s*imag[k+n1]) >> 15; 96 Wi = (s*real[k+n1] + c*imag[k+n1]) >> 15; 97 real[k+n1] = (real[k] - Wr) >> 1; 98 imag[k+n1] = (imag[k] - Wi) >> 1; 99 real[k] = (real[k] + Wr) >> 1; 100 imag[k] = (imag[k] + Wi) >> 1; 101 */ 102 /* End standard 32-bit code */ 103 104 /* Code for TI TMS320C54X series */ 105 106 Wr = ((long int)(c*real[k+n1]) - (long int)(s*imag[k+n1])) >> 15; 107 Wi = ((long int)(s*real[k+n1]) + (long int)(c*imag[k+n1])) >> 15; 108 real[k+n1] = ((long int)real[k] - (long int)Wr) >> 1; 109 imag[k+n1] = ((long int)imag[k] - (long int)Wi) >> 1; 110 real[k] = ((long int)real[k] + (long int)Wr) >> 1; 111 imag[k] = ((long int)imag[k] + (long int)Wi) >> 1; 112 113 /* End code for TMS320C54X series */ 114 115 /* Intrinsic code for TMS320C54X series */ 116 /* 117 Wr = _ssub(_smpy(c, real[k+n1]), _smpy(s, imag[k+n1])); 118 Wi = _sadd(_smpy(s, real[k+n1]), _smpy(c, imag[k+n1])); 119 real[k+n1] = _sshl(_ssub(real[k], Wr),-1); 120 imag[k+n1] = _sshl(_ssub(imag[k], Wi),-1); 121 real[k] = _sshl(_sadd(real[k], Wr),-1); 122 imag[k] = _sshl(_sadd(imag[k], Wi),-1); 123 */ 124 /* End intrinsic code for TMS320C54X series */ 125 } 126 } 127 } 128 return; 129 }

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Digital signal processing laboratory (ece 420). OpenStax CNX. Sep 27, 2006 Download for free at http://cnx.org/content/col10236/1.14
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