help for Multichannel Audio Board for DA830 EVM / OMAP-L137

Hi Pengfei

The multichannel audio daughter board is primarily supported for the DA830 offering. So please keep in mind that the discussion on the forum post w.r.t to the software offerings and constraints

http://e2e.ti.com/support/dsp/tms320c6000_high_performance_dsps/f/115/p/55919/200728.aspx#200728

Having said that the audio daughterboard is compatible with both the DA830 EVM and OMAPL137 EVM, and would require the base EVM to evaluate the audio board. As Jayant mentioned in the previous post the EVM does support a mic input.

You can find the details of that in the technical reference manual

http://support.spectrumdigital.com/boards/evmomapl137/revd/files/EVMOMAPL137_TechRef_RevD.pdf

(Pg 17).

Hope this helps. Let us know if you have additonal questions

Regards

Mukul

Hi Mukul,

Thank you for your reply.

Now I mainly focus on microphone array signal processing, so I have to find an audio board with multi mic-input channels. Although the OMAPL137 EVM can directly support a mic input, I still have to evaluate the possibilty to connect the microphone array to the audio daughterboard. What do I need to do to port the mic signals into the daughtboard? Is there an additional board that transform the mic sinals to line-in signals which is compatible to the audio daughtboard? Can I make a preamplify board by myself to do the transforms? Is there any reference?

Pengfei

I am not aware of any additional boards available besides the one discussed. As I mentioned before that even the audio board is not widely supported for the OMAPL137 EVM (even though it is compatible) , as the board was designed specifically for the DA8xx device support. 

I am following up with some other experts, to see if we can make any more generic recommendations for your query on microphone array input requirements and how it can be matched up w/ the OMAPL137 EVM.

Will get back to you.

Regards

Mukul

Mukul

Thank you very much for your help!

Looking forword to your reply~

Hi,

I just want to confirm what Mukul said: the multichannel audio card has eight analog LINE LEVEL inputs.  We don't have anything available to go from mic level to line level (if it were the other way and you were going line level to mic level, that's easier...you can pretty easily implement an attenuation circuit).  You basically need a preamp(s)...mic level is in the mV range and line level is up to around 2V, i think.  But yeah, you need a preamp and there are lots of those out there, unfortunately the good ones are not cheap.

Bobby T.

Hi !

    I have found a 8-channel preamp(s) , and i have another question :

    i have found a DSK_AUDIO4 daugtercard (http://www.educationaldsp.com/stockproduct_dsk_audio4.htm) which is four channel , i want to know if it is suitable

for OMAP_L137 . I know their interfaces are not matched , did i need a bus conversion interface??

Hi Bobby

    I have known how to handle the hardware interface between this mutlichannel audio board and microphone array. My problem now is: is there DSP/BIOS driver for this multichannel audio board? If no, can you provide some reference that i can modify to make the multichannel audio board work for C6747 EVM?

Hi, I don't know anything about the board you pointed to, but if it's made for the 6713 DSK, it won't plug directly into the L137/6747 DSK.  Completely different connector and pinout.