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You will implement a multirate system that includes three fininte impulse response filters. The sample-rate compression and expansion factors can be controlled in real time using a MATLAB graphical user interface.


Before implementing the entire system shown in Multirate Processing: Introduction , we recommend you design a system that consists of a cascade of filters FIR 1 and FIR 2 without thesample-rate compressor or expander. After verifying that the response of your two-filter system is correct, proceed toimplement the complete multirate system and verify its total response. At first, use fixed compression and expansionfactors of D U 4 . After you have verified that the multirate system works at a fixed rate, you should modify your code so that therate can be changed easily. Later, you have the option of controlling this factor in real-time using a MATLAB interface. Regardless of whether you choose to use the MATLAB interface, you must be able to quickly change the compression and expansionfactors when you demo your code .

Compressed-rate processing

In order to perform the processing at the lower sample rate, implement a counter in your code. Your counter willdetermine when the compressed-rate processing is to occur, and it can also be used to determine when to insert zerosinto FIR 3 to implement the sample-rate expander.

Some instructions that may be useful for implementing your multirate structure are the addm (add to memory) and bc (branch conditional) instructions. You may also find the banz (branch on auxiliary register not zero) and the b (branch) instruction useful.

Real-time rate change and matlab interface (optional)

A simple graphical user interface (GUI) is available (as mrategui.m , which requires ser_snd.m ) that sends a number between 1 and 10 to the DSP via the serial port. This canbe used to change the compression and expansion factor in real time.

Run the GUI by typing mrategui at the MATLAB prompt. A figure should automatically open up with a slideron it; adjusting the slider changes the compression and expansion factor sent to the DSP.

The assembly code for interacting with the serial port, provided in the handout Core File: Serial Port Communication Between MATLAB and TI TMS320C54x , stores the last number that the DSP has received from the computer in thememory location labeled hold . Therefore, unless you have changed the serial portion of the givencode, you can find the last compression and expansion factor set by the GUI in this location. You need to modify yourcode so that each time a new number is received on the serial port, the compression and expansion factor ischanged. If a "1" is received on the serial port, the entire system should run at the full rate; if a "10" isreceived, the system should discard nine samples between each sample processed at the lower rate.

Note that the READSER and WRITSER macros, which are used to read data from and send data to the serial port, overwrite AR0 , AR1 , AR2 , and AR3 registers, as well as BK and the condition flag TC . You must therefore ensure that these registers are not used by your code, or that you save andrestore their values in memory before you call the READSER and WRITSER macros. This can be done using the mvdm and mvmd instructions. The serial macros set up the AR1 and AR3 each time they are called, so there is no need to change these registers beforethe macros are called.

More detail about the READSER and WRITSER macros can be found in Core File: Serial Port Communication Between MATLAB and TI TMS320C54x .

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
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.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
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
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
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Source:  OpenStax, Ece 320 spring 2004. OpenStax CNX. Aug 24, 2004 Download for free at http://cnx.org/content/col10225/1.12
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