<< Chapter < Page Chapter >> Page >

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

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
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
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
Privacy Information Security Software Version 1.1a
Got questions? Join the online conversation and get instant answers!
QuizOver.com Reply

Get the best Algebra and trigonometry course in your pocket!

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
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'From matlab and simulink to real-time with ti dsp's' conversation and receive update notifications?