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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

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
I rally confuse this number And equations too I need exactly help
But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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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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