Does cirrus logic audio card support real time processing?

http://wiki.linuxaudio.org/wiki/raspberrypi for some background information on audio processing. This sounds like a great project to do. Please let us know what you discover.

Thanks,

Clem

HI Clem Martins

Thank you for the valuable information; in fact, i'm still know to raspberry pi, linux, and cirrus logic audio card, i'll try if the steps in the link would works with me since they are for USB cards and hopefully i'll get some where.

i appreciate your help.

Mohammed

"I'm trying to read an input signal from two microphones then add the two signals and output them to the output line in real time."

It is possible to mix the 2 microphone inputs together and then route them internally in the WM5102 to the line outputs. You need to create a specific setup script file to match the configuration you need. The WM5102 datasheet and alsa mixer will help. There are examples of this within the forum, see the following as an example

http://www.element14.com/community/thread/32524/l/is-it-possible-to-send-audio-from-spdif-in-to-the-lineout-using-the-mixer

Hi Scott Hendry

thank you for the helpful informations. i think you direct me to the right direction. i looked to the link and in particular to

2. Re: Re: Is it possible to send audio from "SPDIF In" to the Lineout using the mixer?

Ragnar Jensen

post. He attached script to run equalizer. i tried to run the same script as starting point but when i run the script i got three lines of this message

amixer:Cannot find the given element from control hw:sndrpiwsp

and this after i changed the CARD from hw:0 to hw:sndrpiwsp. i then tried to look to the WM5102 datasheet but its very long and i did not understand.

i appreciate if you have any suggestions

Mohammed

Hi Scott Hendry

thank you for the helpful informations. i think you direct me to the right direction. i looked to the link and in particular to

2. Re: Re: Is it possible to send audio from "SPDIF In" to the Lineout using the mixer?

Ragnar Jensen

post. He attached script to run equalizer. i tried to run the same script as starting point but when i run the script i got three lines of this message

amixer:Cannot find the given element from control hw:sndrpiwsp

and this after i changed the CARD from hw:0 to hw:sndrpiwsp. i then tried to look to the WM5102 datasheet but its very long and i did not understand.

i appreciate if you have any suggestions

Mohammed

Hi Mohammed!

I wrote that script for the older Wolfson Audio Card.

The error messages are because the old drivers have some controls that don't exist anymore.

The controls in question are "RX Playback Switch" and "TX Playback Switch", you can remove any lines with them from the script.

There are some more scripts (also for the Wolfson card)  to look at here:http://www.element14.com/community/message/114756/l/re-read-in-from-the-headset-jack-and-read-out-to-the-amplifier#114756

and a brief description of the Wolfson card's in- and outputs here: http://www.element14.com/community/message/114760/l/re-a-lot-of-playback-items#114760

I have not had the time to test/update my scripts for the Cirrus card, it's likely you have to tweak them yourself. But I hope those links can serve as a start.

--

Ragnar

Hi Ragnar

Thank you so much. I tried the listen_to_LineIn_on_Lineout.sh script with some changes and it did work. However, it turned out i can not do the real time processing by simply mix the two inputs. I read in the WM5102 datasheet that we con program a DSP space that can do signal processing. Do you have and tips about how to use the DSP?

And I need to record two mics from the lineIn to two different fils. I set the hardware

1. amixer -Dhw:0 cset name='IN3L Digital Volume' 138 
2. amixer -Dhw:0 cset name='IN3R Digital Volume' 138 
3. amixer -Dhw:0 cset name='AIF1TX1 Input 1' IN3R 
4. amixer -Dhw:0 cset name='AIF1TX2 Input 1' IN3L 

then used arecord -d 10 -Dhw:sndrpiwas -c 2 -f s16_LE -r wav 96000 -t wav -I mic1.wav mic2.wav

but i got this error: arecord: Set_params:1076: Access type not available.

I appreciate any help

Mohammed