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The following lines of code were borrowed from the C FFT to serve as an example of arithmetic operations in C. Savethis code in a file called mathex.c and compile this file by typing c_asm mathex.c at a command prompt. Look at the resulting assembly file and investigate the differences betweeneach block. Be sure to reference page 6-10 of the compiler user's guide to findout what the state of the FRCT and OVM bits are. Run this program on the DSP, halt the program, and compare theoutput values in a memory window. Does each block work properly for all possible values?

int s1, s2; int t1, t2; int i1, i2; int n1 = 16383, n2 = 16382, n3 = 16381, n4 = 16380; void main(void) { /* Code for standard 32-bit hardware, */ /* with x,y limited to 16 bits */ s1 = (n1*n2 + n3*n4) >> 15; s2 = (n1 + n2) >> 1; /* Code for TI TMS320C54X series */ t1 = ((long int)(n1*n2) + (long int)(n3*n4)) >> 15; t2 = ((long int)n1 + (long int)n2) >> 1; /* Intrinsic code for TMS320C54X series */ i1 = _sadd(_smpy(n1,n2), _smpy(n3,n4)); i2 = _sshl(_sadd(n1, n2),-1); while(1); }

Compiling and linking

A working program can be produced by compiling the C code and linking assembly modules and the core module. The compilertranslates C code to a relocatable assembly form. The linker assigns physical addresses on the DSP to the relocatable dataand code segments, resolves .global references and links runtime libraries.

The procedure for compiling C code and linking assembly modules has been automated for you in the batch file v:\ece420\54x\dsptools\c_asm.bat . The name of the first file becomes the name of the executable. Once you havecompleted lab4main.c and c_fft_given.asm , type c_asm lab4main.c c_fft_given.asm to produce a lab4main.out file to be loaded onto the DSP. For the C FFT type c_asm lab4main.c lab4fft.c to produce lab4main.out . Load the output file onto the DSP as usual and confirmthat valid FFTs are calculated. Once valid output is obtained, measure howmany clock cycles it takes to compute both the assembly and C FFT.

Reference implementation of a psd estimator

We provide for you in Appendix D and E a complete C implementation of a PSD estimator. The input is an IIR-filtered pseudo-noise (PN)sequence generator and the PSD estimate is based on windowing the autocorrelation with a rectangular window.The code consists of the files lab4bmain.c , lab4b.h , intrinsics.h , pn.c , iirfilt.c , autocorr.c , c_fft_given_iirc.asm , and the previously-given TI FFT routine. The assembly file c_fft_given_iirc.asm differs from c_fft_given.asm in that the window array has been removed and variables and arrays associated with IIR filtering havebeen added. Note that the multiply functions in the functions are actually compiler directives contained in intrinsics.h . Make sure you know which ones are used and why; note that VPO is not defined by the TI compiler, therefore the corresponding section of the #ifdef statement is not used. Compile and link these files by issuing c_asm lab4bmain.c pn.c iirfilt.c autocorr.c c_fft_given_iirc.asm at the command line. Load lab4bmain.out onto the DSP and run the code. Make sure that anIIR-filtered PN sequence appears on channel 1 and its PSD estimate appears on channel 2.

Questions & Answers

difference between microeconomics and macroeconomic
Ugyen Reply
what is monopoli power
Adzaho Reply
the situation that prevails when economic forces balance so that economic variables neither increase nor decrease
Bombey
what is equilibrium
Kabir
what are the important of economic to accounting students with references
salihu Reply
Economics is important because it helps people understand how a variety of factors work with and against each other to control how resources such as labor and capital get used, and how inflation, supply, demand, interest rates and other factors determine how much you pay for goods and services.
Muhammad
explain the steps taken by the government in developing rural market?
Azeem Reply
contribution of Adam smith in economics
abel Reply
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Dexter
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Patrick
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Amir
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AS
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Umarou
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Amir
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AS
I love this book and i need extra Economic book
Amir
what is the meaning of function in economics
Effah Reply
Pls, I need more explanation on price Elasticity of Supply
Isaac Reply
Is the degree to the degree of responsiveness of a change in quantity supplied of goods to a change in price
Afran
what is production
Humaira
Okay what is land mobile and land unmobile
scor
And what are the resources in land
scor
what is production
Humaira
the proces of using the services of labor and equipmnt together with other in puts to make goods and services availble
Bombey
Okay what is land mobile and land unmobile
scor
Discuss the short-term and long-term balance positions of the firm in the monopoly market?
Rabindranath Reply
hey
Soumya
hi
Mitiku
how are you?
Mitiku
can you tell how can i economics honurs(BSC) in reputed college?
Soumya
through hard study and performing well than expected from you
Mitiku
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Soumya
prepare first, in psychologically as well as potentially to sacrifice what's expected from you, when I say this I mean that you have to be ready, for every thing and to accept failure as a good and you need to change them to potential for achievement of ur goals
Mitiku
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Soumya
Hallo
Rabindranath
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Mitiku
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Momoh
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Isaac
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Isaac
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Afran
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Afran
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OLANIYI
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OLANIYI
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OLANIYI
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OLANIYI
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akinwale
am from Ghana
Jacob
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Charles
Pls economic A level exam tomorrow pls help me
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OLANIYI
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JOSEPH
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Lerato
okay
Umarou
okay
Umarou
hi
Humaira
hi
Liaqat
what is firms
Anteyi Reply
A firm is a business entity which engages in the production of goods and aimed at making profit.
Avuwada
What is autarky in Economics.
Avuwada
what is choice
Tia Reply
So how is the perfect competition different from others
Rev Reply
what is choice
Tia
please what type of commodity is 1.Beaf 2.Suagr 3.Bread
Alfred Reply
1
Naziru
what is the difference between short run and long run?
Ukpen Reply
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Anna
meaning? You guys need not to be playing here; if you don't know a question, leave it for he that knows.
Ukpen
pls is question from which subject or which course
Ada
Is this not economics?
Ukpen
This place is meant to be for serious educational matters n not playing ground so pls let's make it a serious place.
Docky
Is there an economics expert here?
Docky
Okay and I was being serous
Anna
The short run is a period of time in which the quantity of at least one inputs is fixed...
Anna
that is the answer that I found online and in my text book
Anna
Elacisity
salihu
Meaning of economics
Suraj Reply
It will creates rooms for an effective demands.
Chinedum Reply
different between production and supply
babsnof
Hii
Suraj
hlo
eshita
What is the economic?
Suraj
Economics is a science which study human behavior as a relationship between ends and scarce means which has an alternative use.
Mr
what is supply
babsnof
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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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