How can I talk I2s with a GSM modem using BBB? [ +linphone]

Hello I am using Linphone in my BBB and it works fine using the Audio cape, I can talk with my notebook just fine.

I can also use a GSM Modem sending AT commands via RS232 Cape, I can hear and talk in the GSM modem analog input/output just fine, calling my cellphone and etc.

Now I want to take the audio cape out of the way and talk I2S directly with the GSM Modem.

Can someone help me? I am really having a hard time with this task, a north would be great.

Btw I am using Debian Linux arm 3.8.13-bone49 #1 SMP Fri May 2 06:36:13 UTC 2014 armv7l GNU/Linux

Hey André,

Is I2S = Inter-IC Sound?

I saw some info about this a long time ago and idk much about this
subject, but i'll tell you what i know / i think i remember.

U will need to make some DSP stuff, but I don't know which filter u
have to do... I'm not that much into with DSP yet...

But ur modem should have some type of Clock pin as I2C, sampling size
set pin (to set the size of ur readings for DSP) and two pins for
audio in and out.

Audio out should be connected to some ADC... (And Audio in to DAC)

I hope this help you :slight_smile:

Take a look at this http://www.tjaekel.com/T-DAC/ !

Thank you Glauber! Going to take a look at your link