CCS/TMDSLCDK138: MCASP Audio Example Project

Roberto del Pozo Gallardo

Part Number: TMDSLCDK138
Other Parts Discussed in Thread: OMAP-L138

Tool/software: Code Composer Studio

I tried to use this example to play audio from the line in to line out or play a sine to line out but I don't know how to do it.

Which registers do I have to use to receive and transmit audio?

What is the best way to figure out how it works?

over 7 years ago

0 Yordan Kovachev over 7 years ago

TI__Guru**** 161600 points

Hi Roberto,

You can check the McASP example project from Processor SDK RTOS. See the available documentation here:
software-dl.ti.com/.../Device_Drivers.html

You can also refer to the OMAP-L138 Technical reference manual for functional description of the McASP module inside the SoC.

Best Regards,
Yordan

0 Roberto del Pozo Gallardo over 7 years ago in reply to Yordan Kovachev

Intellectual 440 points

If I run the example I only hear some pops sometime.
What could be wrong?

0 Roberto del Pozo Gallardo over 7 years ago in reply to Roberto del Pozo Gallardo

Intellectual 440 points

Pops is not the right word it is more like cracking.

0 Yordan Kovachev over 7 years ago in reply to Roberto del Pozo Gallardo

TI__Guru**** 161600 points

The RTOS team is notified. They will post their feedback directly here.

Best Regards,
Yordan

0 Sahin Okur over 7 years ago in reply to Roberto del Pozo Gallardo

TI__Mastermind 27355 points

Hello Roberto,

Have you already referred to the test setup instructions?

software-dl.ti.com/.../Device_Drivers.html

0 Roberto del Pozo Gallardo over 7 years ago in reply to Sahin Okur

Intellectual 440 points

Yes i did.

0 Roberto del Pozo Gallardo over 7 years ago in reply to Sahin Okur

Intellectual 440 points

So what is wrong?

0 Sahin Okur over 7 years ago in reply to Roberto del Pozo Gallardo

TI__Mastermind 27355 points

Hi Roberto,

Let me see if I can reproduce what you're seeing with the board I have here. I'll reply back here once I have more info.

0 Roberto del Pozo Gallardo over 7 years ago in reply to Sahin Okur

Intellectual 440 points

Did you already find my problem?

0 Sahin Okur over 7 years ago in reply to Roberto del Pozo Gallardo

TI__Mastermind 27355 points

Hi Roberto,

I haven't been able to reproduce this on my board. Please make sure you have done the following:

1. Connect an audio cable from your PC's stereo audio output to the EVM's input (top port).
2. Connect speakers/headphones to the EVM's audio output (bottom port).
3. Load and run MCASP_Audio_lcdkOMAPL138_c674xExampleProject.
4. Play an audio file on your PC. You should be able to hear the audio playing through your speakers/headphones. The PC audio is looped back from the McASP example to the speakers.

Please let me know if you are still seeing the same issue after following these steps.

0 Roberto del Pozo Gallardo over 7 years ago in reply to Sahin Okur

Intellectual 440 points

I don't know why it is working now but it is working.

I uploaded the blink project again and after that I uploaded the MCASP_Audio_lcdkOMAPL138_c674xExampleProject and than It worked.

Now I don't know how to play a square or sine wave to the line out.

I don't know which registers and/or variables I have change.

Could you help me with this or send an example or something to help me?

0 Roberto del Pozo Gallardo over 7 years ago in reply to Roberto del Pozo Gallardo

Intellectual 440 points

Without help I cannot continue my school project. I hope you could help me soon.

Processors

Processors forum

CCS/TMDSLCDK138: MCASP Audio Example Project