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Running the example

Connect an audio source to J14, a speaker / headphone to J4 and check Path #1.

Connect an audio source to J13, a speaker / headphone to J5 and check Path #2.

Principle of operation

The main idea is to create a Simulink environment that reads samples form 4 channels, process them and send them to 4 output channels. The example model is shown in Figure 14.

Simulink Environment for Multichannel Processing

The Simulink driver block is based on the driver described in the previous chapters. Both drivers read and write samples using a double-buffering mechanism, but they differ in the way they activate the processing algorithm.

The algorithm code, in the Simulink environment, runs as a separate free-running task. At the start of the function it checks the semaphore to see if data is ready to read from the buffer – if not then it stays in a wait state until the semaphore is posted by the callback routine (Please refer to section ). Once this has been posted, it reads the data elements from the addresses supplied by the appropriate pointers. Once the algorithm has then processed the data, it writes the data elements from the addresses supplied by the appropriate pointers. After process is concluded, it will wait for the next frame of samples. This process then repeats until halted.

The callback function, in the Simulink environment, needs to set the appropriate pointers each time an EDMA interrupt occur, and post a semaphore for the “Algorithm” task afterwards.

Driver structure

The driver consists of 4 files:

  1. ”aic24_defs.h” – This file contains the definitions of the various registers of the TLV320AIC24.
  2. ”aic24.h” – Needed for the DSP configuration.
  3. ”aic24.c” – Contains the various initialization routines.
  4. “aic24link.c”

The first three files are the same files used for the CCS driver. The ai24link.c file is similar to the user defined file (test.c for example) described in ,

This file contains the following functions and definitions:

Buffers definitions:

Int16 r_data1[DATANUM*NUM_CODECS*BUFS_PER_CHANNEL]; // data buffer for readInt16 w_data1[DATANUM*NUM_CODECS*BUFS_PER_CHANNEL]; // data buffer for readInt16 r_data2[DATANUM*NUM_CODECS*BUFS_PER_CHANNEL]; // data buffer for writeInt16 w_data2[DATANUM*NUM_CODECS*BUFS_PER_CHANNEL]; // data buffer for write

Pointers to each channel buffers (read and write).

Those pointers are used by the Algorithm block in the Simulink model. Int16 *InSig1; Int16 *InSig2;Int16 *InSig3; Int16 *InSig4;Int16 *OutSig1; Int16 *OutSig2;Int16 *OutSig3; Int16 *OutSig4;

An aic24 handle and a semaphore handle

As explained the semaphore will be used to wait for the data to arrive. AIC24_Handle hAIC24; SEM_Obj AIC24_ready_sem;

It calls the AIC24_Init function and also initializes the semaphore. void AIC24LINK_init() {// setting up the AIC24 handle AIC24_InitDefaults(⩓hAIC24, NUM_CODECS, DATANUM, r_data1, r_data2, w_data1, w_data2, AIC24LINK_process);SEM_new(⩓AIC24_ready_sem,0); }

The callback function.

The callback function AIC24LINK_process simply sets the channel buffer pointers (the pointers the model uses) to the correct places and posts on the semaphore. void AIC24LINK_process(Int16 *r_data, Int16 *w_data) {InSig1 = r_data; InSig2 = r_data + DATANUM;InSig3 = r_data + DATANUM*2; InSig4 = r_data + DATANUM*3;OutSig1 = w_data; OutSig2 = w_data + DATANUM;OutSig3 = w_data + DATANUM*2; OutSig4 = w_data + DATANUM*3;SEM_post(⩓AIC24_ready_sem); }void AIC24LINK_wait() {SEM_pend(⩓AIC24_ready_sem, SYS_FOREVER); }

Questions & Answers

how can chip be made from sand
Eke Reply
are nano particles real
Missy Reply
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
Lohitha
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
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..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
has a lot of application modern world
Kamaluddeen
yes
narayan
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
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
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
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
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
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
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Source:  OpenStax, From matlab and simulink to real-time with ti dsp's. OpenStax CNX. Jun 08, 2009 Download for free at http://cnx.org/content/col10713/1.1
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